Stumble and Backfire during accel
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=33588
Printed Date: October-08-2024 at 6:36am
Topic: Stumble and Backfire during accel
Posted By: ski_in6
Subject: Stumble and Backfire during accel
Date Posted: May-15-2014 at 1:48am
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I have a 92 Ski Nautique with a carbureted 351. Last season, it started hesitating intermittently under hard acceleration. Finally it got to where it would not pull up a skier - hesitation, loss of power and backfires. IT does this warm or cold. If I give it less throttle and ease my way up, it runs wide open just fine, which makes me think it's not fuel filter. I have rebuilt the carburetor with help from a friend. No effect. I just changed the fuel filter anyway, and have not had a chance to run it yet (other than idle - it still idles fine). The engine still has the Pro Tec ignition, which I know is very problematic, but it does not seem to fit what people describe as typical failures for that system. Any thoughts would be appreciated. ------------- KAI |
Replies:
Posted By: Orlando76
Date Posted: May-15-2014 at 2:47am
| Slipped timing? |
Posted By: levinmark
Date Posted: May-15-2014 at 9:10am
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I had the exact same issue with our 96' and it turned out to be that the secondaries were not opening due to corrosion. Maybe check those and see if you can move them? ------------- levin |
Posted By: TX Foilhead
Date Posted: May-15-2014 at 9:17am
| That's similar to the way my ProTec died. For years we used about half half throttle to ease everyone out of the water, then one summer it started taking more throttle and and by the end it was open it all the way and wait a little. Never had an issue with backfiring or hard starts. I had a brand new carb at the time so it was running absolutely flawless and the Perfect Pass was able to handle the driving duties. I'm sure without those things the problem would have been more noticeable much quicker. |
Posted By: Waterdog
Date Posted: May-15-2014 at 9:22am
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I don't think the timing is ajustable with a Pro-tec and they ARE problematic. 1) It could be a coil pack braking down. 2) Check the spark plugs and wires if there all firing tan in color thats good. 3) Check for a vacuum leak by spraying wd 40 or carb cleaner LIGHTLY around the base of the carb and at the intake/head gaskets. Easy to do and pretty much free. ------------- - waterdog - http://www.correctcraftfan.com/diaries/details.asp?ID=3896&sort=&pagenum=2&yrstart=1978&yrend=1978" rel="nofollow - 78 Ski Tique |
Posted By: tahoegaper
Date Posted: May-19-2014 at 3:01pm
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OK I am in this same situation. I have a '92 SNOB has about 1200 hours. I have converted the protect to a standard distributor system, then rebuilt the carb, then installed a brand new carb. I have the same symtoms as above: starts right up pulls wells off the start then after about 10 minutes I can so from WOT to 20 MPH and then to stop and they the engine seems to load up and choke out. I have replaced spark plugs several times in this process, and the ignition work was done by the dealer. I am at a loss on our what to do next. I am ready to sell and be done with it, as my wife and I now have twin 1 year olds and we can not trust the boat we have loved for 13 years. Help TG |
Posted By: desertskier
Date Posted: May-19-2014 at 3:12pm
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tahoegaper: Do you know what standard distributor system they installed and how they wired it? If they used the 12V wire coming from the dash it still may be a low voltage problem caused by the dash wiring issues associated with our boats ( I have a '92 also). |
Posted By: tahoegaper
Date Posted: May-19-2014 at 3:32pm
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So it looks to me that they replaced the ignition with: PROTEC RETRO KIT PCM FORD the same one that you can purchase from SkiDim I have not check sparked plugs after yesterdays trip on the river, but have got to think I have basically eliminated the large pieces of this puzzle. Thank you, TG |
Posted By: tahoegaper
Date Posted: May-19-2014 at 3:58pm
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I forgot to mention that I have also replaced the water/fuel separator with a Racor system. Like I said all of the major components that I can think of has been replaced. Thanks, TG |
Posted By: desertskier
Date Posted: May-19-2014 at 5:01pm
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According to the skidim website the replacement system uses a Mallory distributor with an external coil and ballast resistor. I would make sure that there is 12V at the ballast resistor. ski_in6: The symtoms you are experiencing are what mine did before I beefed up the wiring to the ProTec. |
Posted By: Hooty222
Date Posted: May-19-2014 at 11:41pm
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My first gut feeling is accelerator pump not working.. Disregard if too elementary. Good day. ------------- 1986 Ski nautique 351 1988 Barefoot nautique 454 |
Posted By: Tomski
Date Posted: May-20-2014 at 10:41am
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x2 for accel pump. Look down the primaries and have someone open the throttle as you would to take off, there should be a good squirt of fuel going in to each of the primaries. Failure of the pump is a classic for bogging an engine that runs OK otherwise. The pump jets often get overlooked on a rebuild. ------------- Easily Parted From Money |
Posted By: Bri892001
Date Posted: May-20-2014 at 12:20pm
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I agree with the accelerator pump for the first poster. Keith, the key is not only that the accelerator pump is working, but that it's coming in immediately. Make sure adjust out any slop by using the adjuster but on the pump linkage arm. If there's any free play, you'll get that bog. |
Posted By: Bri892001
Date Posted: May-20-2014 at 8:52pm
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Tahoegaper, yours sounds like a textbook overheating coil situation. Another possibility is a fuel vent issue, you could try removing the fuel cap when it's acting up. Or maybe a clogged fuel screen problem. |
Posted By: ski_in6
Date Posted: May-21-2014 at 1:21am
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I have actuated the accelerator pump by hand, and watched the fuel streams into the primary venturis - seems ok, but I don't have much frame of reference. I'll check for slop. Will also look at the plugs. From everything I've read/seen on Youtube about Holleys, it seems more likely a problem with the secondaries. It picks up smoothly off idle, where the accelerator pump is supposed to add fuel. But when I try to open past say 60-70% throttle, that's when it sputters, backfires, etc. Next steps: 1.) check plug condition; 2.) check accel pump linkage; 3.) check for vacuum leaks; 4.) check idle timing; 5.) try loosening fill cap. desertskier: could you elaborate on what wiring you beefed up to the Protec? Thanks for all your input, I hope to run the boat this week and get to the bottom of this. ------------- KAI |
Posted By: 62 wood
Date Posted: May-21-2014 at 1:29am
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Not familiar with that dizzy, have you checked for sticking timing advance plate? Does it have springs and weights? Are they loose? ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1117&sort=&pagenum=6" rel="nofollow - 64 American Skier 62 Classic.. 73 Ski Nautique |
Posted By: desertskier
Date Posted: May-21-2014 at 1:55pm
 A known problem with our boats is the dash wiring. CC wired the instruments in series (daisy chained) rather than using terminal blocks for power and ground and wiring in parallel. There are some very good posts that describe how to correct the dash wiring issues just search for dash wiring. The main symptom of the poor dash wiring is when you turn on your navigation lights the gauges jump or peg. But the daisy chains also affect the ProTec because it gets power from the key switch on the dash. The power (12Vdc Battery) starts at the 50 Amp breaker at the engine (point 22 on the schematic) it is then routed through the main connector back to the dash. It enters the dash at the ignition breaker switch on the right side of the dash. The output of the ignition breaker switch is then daisy chained through the dash wiring and ends up at the input to the key switch. From the key switch it is routed back to the engine 12.5 Amp breaker (point 41 on the schematic). Then the output of the 12.5 breaker is routed to the ProTec pin "P". The main problem is that because of IR voltage drops through the dash wiring the voltage is less than it should be by the time it gets back to the ProTec. I "beefed up" the dash wiring by adding a single wire that goes directly from the output of the ignition breaker to the input of the key switch. This increases the voltage at the key switch and ultimately the input to the ProTec. You can start by turning on the key and measuring the voltage at the 12.5 Amp breaker. It should be close to battery voltage. Mine reads about 11.5 volts after I fixed it. If it is low then there are several options depending on how comfortable you are with wiring. You can add the dash wire or a cleaner fix would be to install a relay at the input to the 12.5 breaker that is controlled by the key switch but gets battery voltage from the 50 Amp breaker and routes it to the ProTec. I guess the first question is do you have a voltmeter and know how to use it? If not they are pretty cheap to buy and easy to use. If you don't know how to use one there are posts with pictures that we can point to and help you through it. |
Posted By: backfoot100
Date Posted: May-21-2014 at 3:14pm
So is this the problem?
Or is this the problem? Two different issues with two different fixes. If it's an inconsistancy issue check the wiring as stated from others. FYI, my brother-in-law has a 92 with the Pro-Tec. He had a problem where the boat ran great until WOT. It would sometimes just die like turning the key off. Not all the time though but started to progressively get worse. When it happened you put it in nuetral and start it like nothing ever happened. Everything about it ran perfect except at WOT. He ended up finding a loose connection in the dash. He couldn't tell me where it was or what it did but he tightened it up and the boat has ran perfect for three years. Start there like others have suggested. ------------- When people run down to the lake to see what's making that noise, you've succeeded. Eddie |
ski_in6 wrote:Posted By: Bri892001
Date Posted: May-21-2014 at 6:12pm
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Here's the thread where I added the dash ground and later added a new positive: http://www.correctcraftfan.com/forum/forum_posts.asp?TID=21901&PN=1&title=added-new-dash-ground-to-93-with-pics" rel="nofollow - http://www.correctcraftfan.com/forum/forum_posts.asp?TID=21901&PN=1&title=added-new-dash-ground-to-93-with-pics That fixed my gauge and perfect pass issues, so I stopped there. It sounds like to get the Protec all the power it needs, you'd want to run a new ignition (Purple) along with the new ground and positive. Might not be a bad idea to just totally replace the Dash to Engine Harness: http://www.skidim.com/prodinfo.asp?number=R121014" rel="nofollow - http://www.skidim.com/prodinfo.asp?number=R121014 |
Posted By: desertskier
Date Posted: May-21-2014 at 7:39pm
| The ProTec gets a solid ground at the motor (point #40 on the schematic). Only the power wire needs to be addressed. |
Posted By: ski_in6
Date Posted: May-26-2014 at 12:27am
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Eddie, It is one problem, not described very well on my part. If there's a dramatic change in throttle setting, the engine misses and backfires. If the throttle change is gradual enough, I can get to full throttle and run full speed. I actuated the secondaries, they don't appear to be stuck. I looked at the spark plugs, cyl 7 was definitely darker and wet when I pulled it out. The rest were light tan or almost white (fairly new plugs). I checked compression, 145-155 psi on all cylinders. I was thinking of putting the timing light on the cylinder 7 wire and just see if it's getting current at all. Desertskier, thanks for the schematic, that really helps. I will check voltage at the 12.5 A breaker (good chance to use my new voltmeter!) ------------- KAI |
Posted By: ski_in6
Date Posted: May-29-2014 at 2:04am
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desertskier, I checked voltage at the 12.5A breaker. With 12.5 volts battery voltage, I get 11.7 volts at the breaker. You mentioned 11.5 volts with the direct wire installed. Am I ok here? Or does something change when the engine is under high load? ------------- KAI |
Posted By: desertskier
Date Posted: May-29-2014 at 12:41pm
| You could check it again with the engine running just to be sure but it looks good. If there is some resistance in the path it will drop more voltage as the current increases. |
Posted By: ski_in6
Date Posted: June-01-2014 at 11:44pm
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I fired the boat in the driveway this weekend, it ran worse than ever, popping and missing. It would stay running at 1500 RPM but was clearly not running on all cylinders. I put the timing light on, and just to see which cylinders were missing, clipped on to each wire in succession. The front 4 cylinders read the correct RPM, but the rear 4 read double (3200 RPM instead of the correct 1600 RPM). It seems to me that the coils are failing and putting multiple sparks, probably at the incorrect timing, to the rear four cylinders. It was running so poorly I am not sure I could verify timing on cylinder 1. This was the worst it's been. My thought is that another ProTec has bit the dust. If someone knows better, please let me know ASAP as I plan to order the distributor conversion kit in the morning. Thanks! ------------- KAI |
Posted By: TX Foilhead
Date Posted: June-02-2014 at 3:17am
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It's the front cylinders that are the problem. ProTec is a waste spark system, it fires 2 plugs at the same time, one is on the compression stroke and the othe is on the exhaust so it doesn't matter. There are plenty of coil packs around, Ford and Chrysler both used them, but there isn't any documentation that I've seen that explains the design enough to know what else might work. |
Posted By: ski_in6
Date Posted: June-05-2014 at 1:14am
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With some help, I've managed to isolate it to a coil (as opposed to the ignition module). I can find 3 coil versions of this coil pack, but not a 2 coil. I assume they are not available anywhere? ------------- KAI |
Posted By: Bri892001
Date Posted: June-05-2014 at 1:30am
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Is it two sets of two? Is the brain box integrated or is it separate? Someone on her once claimed they replaced them with a Cadillac Northstar coil pack set, but no details where ever given. |
Posted By: ski_in6
Date Posted: June-05-2014 at 2:20am
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Interesting you should mention that... I work with a guy who worked on that system. It takes more than just coils, but it could be done. It's more than I am willing to bite off at this point. To answer your question, it's 2 sets of 2 coils each. As TX Foilhead said, it's a wasted spark system. The coils can be unbolted from the brainbox (ignition module). By swapping the coils around I was able to isolate the problem (or at least the worst of the problem) to one coil. An easy test that pointed me in the right direction was simply checking resistance across the coils. I've been told they can all measure the same but still have a bad one, but in my case the resistance was 50% higher on one of the coils. ------------- KAI |
Posted By: ski_in6
Date Posted: June-17-2014 at 2:09pm
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Ok, I finally isolated the problem to the Protec. I bought the conversion kit and have it installed. I plan to run it this evening, but am confused about setting the distributor. There is an ignition pulse every 90 degrees (45 cam angle degrees). I understand any location can be cyl #1, but I don't know how to get the rotor oriented so the timing will be close enough for the engine to run. It could be as much as 45 deg early or 45 deg late. Is there a way to get closer? Also, the PCM instructions call for 5 deg timing. Is there a reason it's later than the 10 deg recommendation with the Protec? ------------- KAI |
Posted By: SNobsessed
Date Posted: June-17-2014 at 4:36pm
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Get #1 piston at TDC on firing stroke. Adjust the dizzy so that the rotor is centered over #1 terminal, then you will be close enough to start it. PCM is being conservative on timing, I would be the same for liability reasons. ------------- “Beer is proof that God loves us and wants us to be happy.” Ben Franklin |
Posted By: Bri892001
Date Posted: June-17-2014 at 4:36pm
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Not sure I follow on the 45 degrees thing. Are you talking about where the dizzy falls into the oil pump drive? Pics? |
Posted By: ski_in6
Date Posted: June-17-2014 at 10:08pm
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Anyone have a picture of how they mounted the coil? I have read the posts about mounting it vertically for longer life. It seems quite constrained with the wire lengths that are provided... ------------- KAI |
Posted By: ski_in6
Date Posted: June-17-2014 at 11:49pm
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There are 8 firings every 720 crank degrees, equally spaced. So the electronic "points" open once every 90 degrees, 45 cam degrees. When I set #1 to TDC and position the rotor cap so that the rotor lines up with the #1 cylinder wire, I don't know where the 'points' are relative to the next ignition event - worst case, I could exactly half way between 2 events, or out by 45 degrees. I just tried to start it. It coughs and backfires, but won't start and run... am checking wires now. ------------- KAI |
Posted By: SNobsessed
Date Posted: June-18-2014 at 12:39am
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Sorry my comment wasn't helpful. Can you use a timing light while engine cranks to find out where you are at? ------------- “Beer is proof that God loves us and wants us to be happy.” Ben Franklin |
Posted By: ski_in6
Date Posted: June-18-2014 at 1:23am
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Proof once again that I'm not a good mechanic - I proved to myself that the rotor went counterclockwise (looking down from the top), but I didn't even think about it when I put the wires on in clockwise order... when this finally dawned on me, and I got them in the right order, it fired up. Thanks very much to everyone who gave input. I couldn't have worked my way through this without your help! ------------- KAI |
Posted By: Bri892001
Date Posted: June-18-2014 at 1:32am
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Ahh, I see what you mean. The dizzy (distributor) is in sync with the camshaft though, not the crankshaft. So, it only turns once with every two turns of the crank and therefore there are 8 firing events per 360 degrees of dizzy spin. Since we're on it, I'll mention one pitfall, make sure your number one cylinder is at top dead center of the compression stroke... not the exhaust stroke. Also, don't overthink the "points" opening aspect. When you loosen the clamp bolt, you get (almost) infinitely fine adjustability. Another words, you could theoretically adjust the timing by one degree or a half a degree of a tenth of a degree, if you were using some sort of robotic protractor hand instead of human fingers. |
Posted By: Bri892001
Date Posted: June-18-2014 at 1:41am
Glad it fired up, nice 
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Posted By: mamigacz
Date Posted: June-18-2014 at 11:48am
Here is where I mounted mine. I had to fab a bracket to make it work. 
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Posted By: gun-driver
Date Posted: June-18-2014 at 12:55pm
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If your ignition is properly wired with the proper parts there is no need to mount the coil vertical. My '85s oil filled has been mounted horizontally since day one no problems. |
Posted By: pcrowley203
Date Posted: June-18-2014 at 7:58pm
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I’ve got a similar problem to that experienced by ski_in6. I’ve got a ’94 Ski Nautique (closed bow) with a Ford 351-based PCM engine with 600 hours on it. She starts right up, and is fine for maybe ten minutes or so. But then, she begins to stumble, and sometimes even dies, when I give it a lot of throttle rapidly. If I inch the throttle up very gradually, she’s fine. At other times, she accelerates fine under heavy throttle, but within a few seconds dies suddenly and completely, as though the ignition key has been turned off. In either circumstance, I remove the distributor cap and replace it. She goes back to operating perfectly, and the cycle begins again. It’s unclear whether the fix derives from removing and replacing the cap, or just from letting the engine sit for a few minutes while if fiddle with the cap. She’s had the problematic Pro-Tec ignition system replaced. She was tuned up spring of last year, at which time the plugs, wires, and distributor cap and rotor were replaced. The carburetor was rebuilt this spring, and the fuel filter changed out at the same time. I just recently replaced the distributor cap again. I had been thinking that the problem was ionization under the distributor cap, and had planned to install a vented cap, but now I’m thinking that’s not likely to be the solution, given the prior entries in this thread. (I’ll probably do it anyway, since a cap is cheap.) Also, the bowl of the distributor is vented. Although I haven’t checked to see whether the vent might be blocked, I doubt that’s the case, as the bowl was new a couple of years ago. I’m now thinking that the problem with the stumbling might be the coil (even though it was new only a year ago), and the outright dying might be a bad connection in the wiring behind the dashboard. Or possibly both symptoms are due to the latter possible cause. Any thoughts? |
Posted By: gun-driver
Date Posted: June-19-2014 at 5:53pm
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Next time it acts up feel the coil to see how hot it is. My guess would be the coil is overheating then by the time you change the cap it has cooled down only to overheat again. What kind of distributor are you running (points/electronic). |
Posted By: pcrowley203
Date Posted: June-19-2014 at 5:56pm
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We felt the coil last time we had this problem and, yes, it was hot. Although I'd expect it to be at least warm when operating normally. How hot is too hot? Such that you can't keep your hand in contact with it for more than a split second? Electronic. |
Posted By: Bri892001
Date Posted: June-19-2014 at 6:43pm
| When you get the outright dying, do you lose other functions? Blower, Navlights, horn etc.? |
Posted By: pcrowley203
Date Posted: June-19-2014 at 6:54pm
| I didn't test the horn or the nav lights, but I think the blower cut out as well. I'll check again next time it happens. You're thinking it's a problem with the wiring behind the dash? |
Posted By: Bri892001
Date Posted: June-19-2014 at 7:27pm
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Well, it could be the key or something. Next time it cuts out, see if you can take an inventory of what still works, and whether or not it is key switched or dash breaker switched. For example, my blower would switch on with just the dash ignition breaker, so if my blower stopped working, I'd be looking at the dash ignition breaker and upstream. Heat increases the resistance of all electrical connections. So, a connections is already loose, dirty or corroded, it's going to act up more when the boat is hot. I'd start by inspecting and cleaning your electrical connections under the doghouse. |
Posted By: pcrowley203
Date Posted: June-19-2014 at 10:12pm
| Thanks. I'll try all of those suggestions. |
Posted By: gun-driver
Date Posted: June-20-2014 at 2:09am
Yes to hot to touch. Is it a electronic conversion(replacing points plate) or a electronic distributor. |
Posted By: pcrowley203
Date Posted: June-20-2014 at 10:04am
| Electronic. Or so the mechanic tells me. I wouldn't know the difference. |
Posted By: pcrowley203
Date Posted: June-20-2014 at 2:27pm
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Sorry. Electronic distributor, I believe. But I don't know the difference between an electronic distributor and a non-electronic distributor. This distributor looks like distributors I've seen on cars vintage the 1960s and '70s. But the marina tells me it's electronic. |
Posted By: Bri892001
Date Posted: June-20-2014 at 2:43pm
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This will help somewhat, but you really need to see under the cap to know: http://www.skidim.com/distributor.asp" rel="nofollow - http://www.skidim.com/distributor.asp Under the cap, an electronic would look something like this:  And points would look something like this: 
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Posted By: pcrowley203
Date Posted: June-20-2014 at 2:48pm
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Thanks. That's very helpful. Next time I'm at the boat this weekend, I'll look. At this point, though, I'm pretty sure it's electronic, based on what the marina has told me. (They did the conversion from Pro-Tec.) Assuming the distributor is electronic, does that suggest any other ideas? |
Posted By: Bri892001
Date Posted: June-20-2014 at 3:14pm
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It sounds like coil. Either the coil itself is bad, or it the ballast resister isn't wired in correctly. It seems like a lot of those Protec to Distributor conversion kits came with a less than great coil. I've heard good things about the MSD Blaster II as a replacement. |
Posted By: pcrowley203
Date Posted: June-20-2014 at 3:35pm
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I believe (although I'm not certain) that these symptoms started well after the conversion was done. That suggests the problem is not that the ballast resistor was wired incorrectly. I suppose it's possible the wiring connections to the ballast resistor are faulty, however. Sounds like the best course of action is: 1. Replace the coil, and 2. Check all wiring connections on the dashboard and the engine, and particularly those to the ballast resistor. |
Posted By: Bri892001
Date Posted: June-20-2014 at 4:46pm
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Sounds like a plan. I'm sure you realize that if you're getting an interruption in your ignition (purple or red), no coil is going to help. But, in the interest of time, it's going to take a few days to get a coil in hand, probably doesn't hurt to order it as it's a likely suspect if you're engine is cutting out and all of your dash functions are still working. |
Posted By: pcrowley203
Date Posted: June-20-2014 at 4:50pm
| You overestimate me. I don't know what you mean by "purple or red" or, for that matter, an "interruption" in the ignition. |
Posted By: Bri892001
Date Posted: June-20-2014 at 5:44pm
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Basically, the dash power source (Battery Positive) wire is red. Usually the ignition wire switched on by the key is Purple. When I say interruption, I mean a break or open in the circuit. This is normally a switch, but if you've got something funny going on like a loose or corroded connection, this is going to act like a "switch" and open or interrupt the circuit. What I was getting at, is your coil needs a steady, un-interruped feed of positive current to work. The positive current wire should be purple, but it might be red. If the circuit is opened (flow is interrupted) then the coil won't do it's job of making spark, no matter how good it is. This diagram should help: 
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Posted By: pcrowley203
Date Posted: June-20-2014 at 5:59pm
| Ah right. Yes, that much I understand. I will check all the connections I can find to make sure they look clean and secure. Thanks for the diagram. That will help make sure I get them all. |
Posted By: pcrowley203
Date Posted: June-20-2014 at 6:13pm
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While I have your attention, do you know the answer to this question: I have a 1994 Ski Nautique closed bow with a PCM engine. The plate on the engine says it's a model PLP-PR-R12PT. My owners' manual seems to say that the boat could possibly be equipped with any one of the following four engine models: PLB, PL&RC, PL&RD, or PL&RP. Can anyone tell me which of those four is mine? What's the logic that maps the number on my engine to one of the models listed in the manual? I can't find anyplace in the manual where this is explained. |
Posted By: Gary S
Date Posted: June-20-2014 at 6:38pm
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I saw that you posted this question yesterday. I am not at all up on the newer engines but I'll say this, the owners manual unlike autos could be very different from what is actually in the boat. Yours may have been upgraded,I do believe that serial prefex is the higher hp one. Write to the factory and see if they will look up the serial number of your hull and if that motor serial number is original to when the boat left the factory. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1711&sort=&pagenum=1&yrstart=1966&yrend=1970" rel="nofollow - 69 Mustang HM SS 95 Nautique Super Sport |
Posted By: pcrowley203
Date Posted: June-20-2014 at 7:01pm
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Wow. It had never occurred to me that the engine might have been swapped out at some point. I bought the boat in 1992, becoming its third owner. At that point, the hours read (for whatever that's worth) 300. The engine looked like old technology, even then. It looks like the pictures in the manual, although those pictures are of poor quality, so it's a bit hard to say for sure. I went onto the CorrectCraft site about a week ago and posed the question to them. I've not had an answer yet. |
Posted By: Gary S
Date Posted: June-20-2014 at 8:07pm
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It very well could have been done at the factory maybe a special order,maybe it was all they had or PCM could supply. Things can change after the manuals have been printed too. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1711&sort=&pagenum=1&yrstart=1966&yrend=1970" rel="nofollow - 69 Mustang HM SS 95 Nautique Super Sport |
Posted By: TX Foilhead
Date Posted: June-20-2014 at 9:11pm
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Most likely the thing that hasn't changed is the engine manual, The specs for the basic Ford and Chevy motors was basically the same for a long time so they didn't update the manual for many years. The additions were usually just an added section so the 83 manual looks pretty much the same as the 93. If you search engine rotation there is a thread that has all the PLR/PLL ect broken down. I keep a pic of my tag on my phone so I can remember what spins which direction so I don't have to guess at it when I'm not around the boat. |
Posted By: pcrowley203
Date Posted: June-21-2014 at 11:28am
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I found this forum entry: http://www.boote-forum.de/showthread.php?t=171927&page=15. It's in German, but if you're using Google Chrome for your browser, the browser will translate the text to English at the push of a button. According to the writer, the encoding goes like this. My engine is a PLP-PR-R12PT. P -- PCM L -- left-rotating engine P -- indicates the horsepower (although exactly what horsepower P indicates, I don't know) P -- PCM "gear" (whatever that means. I'm assuming it means the peripheral equipment attached to the block, such as the ignition system.) R -- reverse or reduction gear (whatever that means. Do any of these boats NOT have a reverse gear?) 12 -- the gear ratio (I thought these boats were always 1:1, no?) PT -- not mentioned in the German forum, but I'm guessing it indicates a Pro-Tec ignition. |
Posted By: gun-driver
Date Posted: June-21-2014 at 12:25pm
| Go to the reference section , click on manuals, page down to the bottom, find PCM service manual page 4 has the code break down. |
Posted By: Gary S
Date Posted: June-21-2014 at 12:33pm
Keep in mind Paul PCM supplies engines for more boats than just correct craft and for boats other than ski boats! PCM gear means its a PCM trans, gear ratio can be different for different types of boats. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1711&sort=&pagenum=1&yrstart=1966&yrend=1970" rel="nofollow - 69 Mustang HM SS 95 Nautique Super Sport |
Posted By: pcrowley203
Date Posted: June-21-2014 at 2:02pm
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Ah HA! Beautiful! Thanks very much. Page 4 of the service manual does indeed have the model number decoded. I had written down "PLP", but that page does not indicate that "P" is one of the options for that third space. Maybe I misread my engine badge, and the character is really a "D". I'll check the next time up at the boat. Meanwhile, however, my gear ratio code is definitely a 12, which is, strangely, not one of the options listed in the service manual. So I wonder what my gear ratio really is (not that I need to know). The missing gear ratio code makes me wonder whether my "PLP" really is a "PLP" after all, and the "P" horsepower code exists, but is also missing from the manual. Again, I'll double check the model number next time I'm at the boat. |
Posted By: pcrowley203
Date Posted: June-23-2014 at 11:21am
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I was at the boat yesterday, and I learned the following: 1. My engine model does in fact start with "PLP", a model number that does not appear in the service manual to which gun-driver directed me. Maybe my 1994 engine is newer than that manual. 2. I went over my electrical connections, both on the engine and behind the dash. None of them seemed obviously loose or so dirty as to block current. 3. I had no incidences of outright dying, so I couldn't check to see which instruments, if any, failed during such events. 4. The coil never became so hot that I couldn't touch it. It definitely got warm, but I could put my finger on it for a good ten seconds without getting burned. 5. It definitely seems that something is getting too warm. Last night, whenever it began to act up, I'd opened the engine cover for a few minutes, then everything was fine. 6. The distributor is electronic. Any thoughts? I continue to suspect the coil, and will likely replace it, since doing so is pretty cheap. Thanks for all your help. |
Posted By: pcrowley203
Date Posted: June-23-2014 at 11:24am
| I can't find a date on that service manual. |
Posted By: SNobsessed
Date Posted: June-23-2014 at 11:56am
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Spray some brake cleaner on the coil or dizzy when it acts up. That should cool it down. Then you will know which to replace. An ice bag may work too! ------------- “Beer is proof that God loves us and wants us to be happy.” Ben Franklin |
Posted By: pcrowley203
Date Posted: June-23-2014 at 12:01pm
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Thanks. I'll try that. I thought about trickling a bit of water onto it, but was afraid the temperature differential might cause it to crack. Why brake cleaner? |
Posted By: SNobsessed
Date Posted: June-23-2014 at 12:05pm
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Brake cleaner came to mind because it is not flammable, at least the can I have says that. ------------- “Beer is proof that God loves us and wants us to be happy.” Ben Franklin |
Posted By: gun-driver
Date Posted: June-23-2014 at 12:07pm
| When I was having troubles with my '85s coil I used a wet rag with ice wrapped in it. |
Posted By: pcrowley203
Date Posted: June-23-2014 at 12:08pm
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Thanks. |
Posted By: pcrowley203
Date Posted: July-21-2014 at 1:05pm
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It's been a few weeks since I last made an entry here. Since then, I have NOT, in fact, replaced the coil. Rightly or wrongly, my mechanic talked me out of it, saying that the coil isn't getting hot enough to be the problem. Meanwhile, the severity of the problem has diminished substantially. There is still some occasional hesitation, but that's all. What's changed? When I put the boat away, I now prop the engine cover open a bit to let the engine have a bit more ventilation. I also leave a bucket of moisture absorbent on the cockpit sole next to the engine. I also find that, when the engine acts up, I open the engine cover for a minute or two, to let it either cool down or dry out (or something, I'm not sure what), and then it runs fine for a while until I have to do this again. I've also noticed that, when the engine is hesitating, the tachometer bounces around quite a bit. All this suggests to me that moisture is causing a problem somewhere in the portion of the electrical system that's under the engine cover. But where exactly? I find it hard to believe that the problem is with a connection. I've checked the connections under the engine cover, and they all seem fine. Any more ideas? |
Posted By: JasonS
Date Posted: July-21-2014 at 2:22pm
| Sounds like something (maybe the coil) is getting too hot, since it gets better when you lift the engine cover and let the heat out. |
Posted By: pcrowley203
Date Posted: July-21-2014 at 4:43pm
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When I experience the hesitation, I stop the boat, open the engine cover, and put my finger on the coil. It's hot to the touch, but not so much that I can't keep my finger on it for five seconds or so. This, according to my local mechanic, strongly indicates that the coil is fine. You disagree? |
Posted By: Bri892001
Date Posted: July-21-2014 at 6:25pm
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The coil is still suspect if you ask me, but heat increase the resistance of all electrical connections. Since the tach jumps around when it's acting up, it sounds possible that the (-) connection on coil is dirty/loose. Check that too. |
Posted By: SNobsessed
Date Posted: July-21-2014 at 8:56pm
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When a coil fails, usually the insulation on the windings starts to break down, which is accelerated by heat (expansion). So it would make sense thst the tach would be affected since the coil resistance would change as it starts to short out. ------------- “Beer is proof that God loves us and wants us to be happy.” Ben Franklin |
Posted By: pcrowley203
Date Posted: September-28-2014 at 9:59am
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It's been two months since I last posted here, and I thought I should provide an update. Rightly or wrongly, I never did replace the coil. My mechanic swore up and down that it wasn't the problem. At his recommendation, I began using a foot-long piece of 2x4 to prop open the engine cover when the boat is not in use. I've also been leaving a bucket of moisture absorber on the boat when it's not in use. I haven't had a problem since I started doing these two things. It seems that the problem is moisture. I can't recall if I mentioned in earlier posts, but the boat stays in the water all season, and wears a mooring cover. Apparently the above steps suffice to drive the moisture levels down to a point where they don't interfere with the operation of the engine. Interestingly, I still notice the tachometer twitching from time to time, which suggests to me that there's still an electrical problem. But it no longer seems to rise to a level that stops the engine from running. Thanks for everyone's input on this. |