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New engine - maiden voyage and ...

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    Posted: June-30-2018 at 10:14pm
So the boat finally made it to the lake today and for the most part was doing well with only one minor hic-up while warming up on the ramp. I noticed a small fuel leak from the LP/ HP fuel pump fittings. Apparently while assembling the two I neglected to fully seat the 90 deg fitting off the LP pump to the HP pump. A quick R & R to tighten the fitting and all was good - still don't know why it wasn't leaking on the hose in the driveway, but at least I caught it before heading out on the lake.   

However, that pesky GT40 surging problem is back ... and with a vengeance! It's worse now than when I first bought the boat. Puzzling, because I had bought a new IAC last fall that had all but cured the problem. And after the winter rebuild, I had taken literally everything apart, cleaned, lubed, painted and whatever else every single part that I was reusing, including the nearly brand new IAC.   Bad weather moved in late this afternoon so I was barely able to get the tower collapsed and boat in the garage before it started pouring so it didn't get a once over tonight, but I will be doing that tomorrow to see if there is an obvious cause.

The question here is assuming I find the IAC is functioning properly, what could possibly cause the surging to be so much worse? I hadn't noticed it before because breaking in the cam/ lifters I was fluctuating the RPM's constantly anyway.   But today it didn't seem like the IAC was functioning ONLY at idle - it seemed to be working overtime even at 1000-1500 rpm. I was under the impression that the IAC was only supposed to play a part at idle but not once throttle is increased.   Any ideas?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SNobsessed Quote  Post ReplyReply Direct Link To This Post Posted: July-01-2018 at 7:51am
Can you rig up a signal generator to control IAC manually (for test)?

If you can rule out an erratic signal, then maybe focus on airflow anomalies.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-01-2018 at 8:27am
Hi Joe

I checked with this guy

and he said he didn't have a clue but that as a guess, an adjustable fuel pressure regulator and gauge might come in handy for some adjustment of your fuel pressure/flow to see if that helps in case it's an issue with the ECM not being able to compensate..

You can probably find one to match your color scheme too. Red, white, blue, black silver or even yellow to match the hull intake
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-01-2018 at 12:31pm
Originally posted by KENO KENO wrote:

Hi Joe

I checked with this guy

and he said he didn't have a clue but that as a guess, an adjustable fuel pressure regulator and gauge might come in handy for some adjustment of your fuel pressure/flow to see if that helps in case it's an issue with the ECM not being able to compensate..

You can probably find one to match your color scheme too. Red, white, blue, black silver or even yellow to match the hull intake


BINGO !!    Found just the right thing ... all the correct colors anyway   
Thanks for the suggestion

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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-01-2018 at 1:13pm
Bet this one in the link would fit, it's a little lacking in the color dept though

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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-01-2018 at 9:48pm
Joe

You didn't mention how the engine ran other than the loping issue, so how'd it run otherwise?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-02-2018 at 6:11pm
Ran great Ken! Smooth acceleration, temps, pressure and volts all perfect. Taking it easy for the first several hours. Ship says 40 hour break-in with the first 10 under 2000 rpm and 3000 for the next 10. I don't know about that, I was going to ask some of the more seasoned guys on the forum that have more experience with Ford platforms than myself.

I had time to get 3 hours in on Saturday but Momma had a home list for Sunday. However I did pull the boat out that evening to go through some things to see if I could track down the problem and I think I found a major contributor to the surging. It seems the throttle position sensor may have been in a bind and not functioning well or at all with the butterfly. After reinstalling it and verifying it's movement, the engine surging   calmed considerably. It still has the typical mild surging when cold but after a minute that goes away and it for the most part will idle very smooth and consistent now, albeit still a little on the high side, about 850-900.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-02-2018 at 6:41pm
Since the TPS and the MAP sensor combine to tell the computer what engine load is so it can make adjustments, it makes sense to me that the TPS not being adjusted right would affect the idle.

Also if you look at page 2A-22 (edit, it's really 2A-23) of the GT-40 manual, it talks about things that will make the computer raise your idle RPM to about 800. That would be a bad (out of range] signal from the ECT sensor, ACT sensor or TPS switch.

Gee that TPS switch keeps popping up in the conversation.

Now as far as that break in period, you obviously misunderstood. They meant minutes instead of hours

You have a few hours on it already,it's time to treat it like it's my boat and you stole it from me.

Could be that your tach reads a little high too
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-02-2018 at 10:54pm
Good input Ken, much of your reasoning about the TPS was mine as well. Didn't know about the GT40 page info, thanks for throwing that out there ... I'll give it a read tonight

I also wanted to express my take on the muffler delete, since I seem to recall some interest in the outcome, or least my opinion after the fact. Personally, I love it - though I can see where a large percentage of folks would not care for the change. THIS is the deep throaty sound that I was looking for and wanted for my boat. I will admit that it is a bit louder at idle - in the water - than I had anticipated given the exhaust outlet is under water while at rest. I don't have a db meter, but if I had to guess I'd say about 10 db louder than I expected and maybe 20 db louder than with the Invertaflo.   I suppose the close proximity of the outlet to the surface plays a huge part in this, something I hadn't considered.
I've always had an I/O drive system in the past and to my knowledge none of them have mufflers, other than the water itself. Yet at rest they are nearly always very quiet - it's only on plane that you'll hear some of the exhaust note (unless of course you have thru-hulls or captains call).   Anyway, to me the elevated exhaust tone at rest was not distracting nor irritating and the on plane sound was nothing short of exhilarating!   I had met a buddy at the lake on Saturday and his opinion was the same, so much so that he spent much of the day Sunday trying to convince his wife to let him eliminate their muffler also. Naturally, that's not going to happen.       But they are much younger with small children, so......
Once again, I understand this is definitely not going to be a choice the majority of the members of CCF would make, but it sure suited me.    
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Post Options Post Options   Thanks (0) Thanks(0)   Quote MrMcD Quote  Post ReplyReply Direct Link To This Post Posted: July-03-2018 at 5:05am
Glad it is going well for you now.
All the new parts in your engine are seated well by now. Running an engine in a boat is exactly like running it on a dyno. There is a load all the time.
This is actually great for engine break in as long as you watch the temps and make sure to not get it hot.
Cylinder temp is just as important as coolant temp.   Running hard for any length of time will heat the cylinder in the head chambers.   This heat can will affect your new pistons.
That is why you should not run it hard for any length of time while it is new.
Ski speeds are only 3,000 to 3,500 and not hard on the engine.   I would not hesitate to ski right now with your new engine.   The quick load pulling out a skier is good for seating your piston rings.
Rev it if you wish to feel how fast it might be but back it down to cool right away don't hold it at 4,800 RPM for any period of time, when it gets there back off and let it cool.
If it ever starts to lay down, power starts to fall off even though the throttle is still down quickly back off and let it cool. That would be detonation robbing power.   Should not happen if all is operating well but if it does and you don't back off the throttle things go bad quick.
If it was assembled correctly and you don't get it hot you are good to go. Enjoy it.
Curious what your top speed and acceleration and RPM will be with your new engine compared to the old. I just installed a new Acme 422 and hope to get some time on the water this week. We can compare notes.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-03-2018 at 3:15pm
Will do Mark - planning on heading out again this weekend. I'd like to go out tomorrow, but big family dinner etc. planned in KC.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote MrMcD Quote  Post ReplyReply Direct Link To This Post Posted: July-08-2018 at 1:23pm
I went out yesterday afternoon, bad timing everyone was out there and water was terrible.
2-3 foot rollers take the fun out of it for a skier.
There were 3 or 4 of the 23 foot giant wakeboard boats loaded with 8-12 people and fat sacks putting out 4-5 foot tall waves. They were having fun but destroyed the lake for all others. ( shame this is legal )   I did not get to ski.
The 422 was smooth, no doubt.   I did not get to test for top speed.
My nephew wakeboarded and I found I was taching 2,400 RPM to pull at 20-21 MPH.
RPM was higher at this speed than with my older 224 prop.
At 30-35 MPH the RPM seemed to match MPH.
Did not get to test wide open at all, water was just to rough for most of the outing.
It was hot and the water temp was great to swim in so worth the outing.
I will get it out in better conditions and record the prop notes.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-08-2018 at 9:18pm
Well Mark I didn't get to go out yesterday - too much to do around the house and the wind was up a little high (big surprise in Kansas, lol). However I did get out this morning till about 2 or so. Big difference and as it turned out, the opposite experience that you had. All in all we had a great day with better than average boating conditions, warm weather without being HOT with the boat running very well - for the most part (more on this later).
Got out there early and there not only were few other boats on the water but very little wind which made the lake perfect for general boating and some 'testing'.
So here's what I've got so far: 25mph @ 2400rpm; 30mph @ 2800rpm; 34mph @ 3000rpm and at 3500rpm I would range from 41 to 43mph depending on the trailing winds or head winds. Direction of travel and wind direction didn't seem to matter much at all anywhere below the 3000 rpm mark. All of the speed #'s were GPS and my tach has been verified with a digital tach while on the hose at home.
I didn't feel comfortable quite yet opening her up to WOT so my limit today was about 3900rpm, which at the moment I glanced at the speedo was somewhere in the vicinity of 46-47mph. Elevation at El Dorado lake today was @ 1334.9 feet.

I think for the most part your normal RPM vs MPH will be a bit higher for the MPH than your RPM, especially being closer to sea level? than myself. I've observed in the past that regardless of low wind speed, rougher seas will reduce this somewhat and sometimes markedly so I'd think your top end with the 422 should fall around the 50mph+ range given good smooth boating conditions.

Now for the bad: The surging, unfortunately, is back. And today it was back with a vengeance. So much so that it was genuinely hard to keep the boat running anywhere below about 1200rpm while out of gear. While in gear once it settled, 1000-1100 rpm's seemed to be it's lower limit - much less than that and the dreaded surging would rear it's ugly head. Honestly, I'm really perplexed why I would get fairly smooth idles after the engine warmed in the driveway and as soon as I make it to the lake the surging not only comes back but is the worst it's been yet. As always, I'll do some more research and checking myself, but I'm open to any suggestions here .....

edit: one last note is that on several occasions while idling, or trying to idle, I would catch a whiff of fuel. Kind of reminded me of a carb engine that is running rich.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote MrMcD Quote  Post ReplyReply Direct Link To This Post Posted: July-08-2018 at 9:54pm
The EFI tunes based on signals from your sensors and a pre programmed data base.
My guess is one of your sensors is sending a bad signal to your ECM.
These can be checked to see if they are sending the right voltage at the right time.
I only know the basics and would have to research each component if I had the same trouble. Glad you found good water. What prop is on your boat? Your RPM's are well below mine for the same speeds.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-08-2018 at 10:04pm
Same as yours ... 422.   Don't know how much weight you were carrying, but we had roughly 200 lbs of gear, a completely full tank of fuel and about 500 lbs for the people factor. And of course there's the tower and all that related gear ( speakers, racks, amp, second battery, etc). Not sure about how much all that is but I'd guess somewhere around 350-400 lbs.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-08-2018 at 10:17pm
Originally posted by MrMcD MrMcD wrote:

. What prop is on your boat? Your RPM's are well below mine for the same speeds.


One of you has numbers that make sense, the other one has way out of whack numbers.

Yours make sense Mark
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-08-2018 at 11:02pm
Well I don't know what to tell you Ken. Had my daughter verify and log in all the recorded data in her phone to be sure I got it all straight.   The only thing that may be different is that when the MC dealership replaced all the damaged parts last winter they didn't give me a brand new 422 prop like they were supposed to. I noticed it was a refurbished prop while reinstalling it this spring. Perhaps the shop that refurbished the prop didn't get it true to the original ... too much pitch or cup?   IDK, but them's the numbers of the day   
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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-08-2018 at 11:02pm
In the perfect world with no friction, no slip, 100% efficiency 3900 rpm would give 46.5 mph with a 15.5 inch pitch prop.with a 1.23 to 1 transmission

Now throw in 15% prop slip and that 3900 rpm gives you about 39.5 mph



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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-08-2018 at 11:31pm
Yeah, I know the math Ken and I agree it's weird and doesn't add up. I didn't really think about it much till you said something. But no joke and no fudging .... those are the numbers so I don't know exactly what is amiss. Where the difference in the statistical math and the mechanical stats is ...???   You've got me. Like I said, I can't verify the EXACT pitch of the prop since it is a reman, and I have no idea who it was that did the job.
One thing I haven't done is verify the GPS speedometer accuracy .... perhaps it's not calibrated right? Can they even be that far off? Guess I'll have to check that as well next time out.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-09-2018 at 7:05am
This is like deja vu all over again

A link from last year

link

Your tach vs speed numbers from yesterday seem to diverge further and further from each other as you go faster

I'd be looking again at that tach and speedometer before thinking you have a magic prop on there
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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-09-2018 at 7:25am
Originally posted by gt40KS gt40KS wrote:

I'm really perplexed why I would get fairly smooth idles after the engine warmed in the driveway and as soon as I make it to the lake the surging not only comes back but is the worst it's been yet. As always, I'll do some more research and checking myself, but I'm open to any suggestions here .....

edit: one last note is that on several occasions while idling, or trying to idle, I would catch a whiff of fuel. Kind of reminded me of a carb engine that is running rich.


I think like Mark said, sensor issues.

In the driveway it never sees any load, then you take it to the lake and run it under loaded conditions and one or more sensors isn't responding right or adjusted right
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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-09-2018 at 10:33am
Originally posted by KENO KENO wrote:

This is like deja vu all over again

A link from last year

link

Your tach vs speed numbers from yesterday seem to diverge further and further from each other as you go faster

I'd be looking again at that tach and speedometer before thinking you have a magic prop on there


Looking back, you had the same speed vs RPM issue with the prop you banged up so I don't think you had 2 magic props.

You might want to look at the big manual, page 6-4 at the tach wiring diagram and figure out if your new tach needs the 22,000 ohm resistor that's in the wiring to the tach from the coil Page 2A-16 has some mention of the resistor being there for marine tachs. Not very wordy or specific..I don't know the difference between a "marine" tach and a "non marine" tach.

If I was me, which I am, I'd probably bypass the resistor and see how the tach works but that's just me

Or you could call Faria and see what they tell you.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-09-2018 at 6:03pm
The tach issue was solved last year, or so I thought. There were two different connection setting labels were affixed to the tach and of course I was setting it using the wrong one. RPM has now been verified with two different digital tachs and it is right on the money with all 3 reading virtually the same. The other 2 were induction type so they keyed off of the spark not the ECM or the boat tach wire.   Maybe I'm missing something here but I can't see how both of the other tachs could be giving the exact same false reading as the one on the dash...   

It also occurred to me that last year I had tested the new prop & shaft 2 or 3 times before the 'incident' and was coming up with much the same figures as Mark anywhere below 3000rpm or so. After that the MPH trailed off drastically, probably due to the lack of power, or the power it was supposed to have.   At 4800rpm I was only able to get to 41 or 42. Nothing in the dash has been touched since then and the only thing I did with the ECM and other wiring was replace the old breakers and relays. Only differences has been the new engine and the different refurbished prop than I had during those tests. So what am I not seeing here?

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Gary S Quote  Post ReplyReply Direct Link To This Post Posted: July-09-2018 at 6:29pm
What are you using for a gps unit?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-09-2018 at 6:50pm
Open and read this link Joe. Same link as yesterday

link


It your's from when you had it out after you replaced the gauges and a bunch of other stuff.

You thought 3500 rpm and 42 mph seemed odd then

Yesterday you had 3500 rpm and 41 to 43 mph...................consistently odd or maybe oddly consistent.

Back when you "calibrated" your Faria tach against some old one you had you had them close at 1500 rpm. Have you checked your Faria at 3500 rpm against the digital stuff? I've had tach's that were accurate at low speed and got farther and farther off as the rpm's went up.

Your 4800 rpm and 42 mph was with the original tach and original prop. You were figuring the tach read high.

All this info is from your old threads

Here's your original thread where you thought the tach that came with the boat read too high

original thread

Your tach or your GPS is off is what you're missing.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-09-2018 at 8:15pm
Perhaps Ken ... perhaps. I'm going to take the digitals out with me this next week to check the tach while under load. I'll also recheck the GPS. again with the the GPS app. I've got a buddy that is out most weekends as well. He's got a 2014 Axis with a GPS speedo in his boat also so I'll have him shadow me to double, double check the GPS.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-11-2018 at 10:11pm
Tuesday we had a little hic-up at work and my son said "we should just go to the lake!"   So we did. We had two different GPS apps on two different phones to confirm the speed but I had the digital tach's set out to take and forgot about them after setting up the tower.
Though I can't confirm the accuracy of the tach yet, the GPS speedometer was confirmed to be accurate by both of those apps (again, on two separate phones) up to the top speed we had recorded which yesterday was only about 41-42.   Strangely, that speed was shown this time to be at 3900 rpm, which does kind of point to a problem with the tach. However, all of the speed/ tach #'s that I listed above up to and including the 34mph@3000 were exactly the same. Like I said, strange. If the tach registered differently this time @ 3900 you'd think the others would be different than before as well.   



Looking forward to the weekend at this point and NOT forgetting the other tachs
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Post Options Post Options   Thanks (0) Thanks(0)   Quote MrMcD Quote  Post ReplyReply Direct Link To This Post Posted: July-25-2018 at 3:31am
We were out for a 4 day camp/ski trip last weekend.   I took my Garmin to check on the new Acme 422 Performance. I am quoting from memory but should be accurate.
At 30 MPH I now tach about 2900 RPM, at 36 MPH it is just about dead on 3,600 RPM.
At 40 MPH I was dead on 4,000 RPM.
Top Speed now with one on board and a full gas tank was 46 MPH at 4,800 RPM.
It is extremely smooth and feels powerful.
If I had it to do over I would have ordered the 224 Acme again.   It allowed 5,200 RPM and consistently 48 MPH, one time it hit 5,300 RPM and 50 MPH and was equally smooth till it was damaged.
I can't feel by seat of the pants if one is stronger pulling skiers, power has not been an issue with any of the props, the GT40 runs really well.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-26-2018 at 6:54pm
Sounds like either would do great for a single. If you ever plan to pull doubles or more, by your numbers I'd say the 422 probably will have a bit more on the bottom end, of course sacrificing the top.   I haven't made it out to the lake since everything's been fixed    and unfortunately we're heading out this weekend for an out of town job for the next 2 weeks so It'll be a while longer before I can get true numbers. But judging from my previous data and how far off the tach was, my correct numbers are probably nearly the same as yours.
I've gotta say though that the Reman prop the MC dealer gave me last winter isn't balanced nearly as well as the new one I had bought last fall and I'm also thinking that the pitch isn't quite right either. I've been thinking about buying another NEW prop and putting this one on the shelf as a back-up for just that reason.   Now that you've said you would probably have gotten the 224 instead, perhaps I'll have to reconsider getting another 422   
JCCI
1995 Ski Nautique GT40
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Grand Poobah
Grand Poobah


Joined: June-05-2004
Location: United States
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Points: 3478
Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-26-2018 at 9:29pm
Don't forget that you might have 30 or 40 more horsepower to harness with a prop.

I think I'd wait and get some numbers with this one before just ordering a new one.

I was thinking that if you left the boat and the keys, I could drive out and pick up a few other CCF'ers along the way and we could do a slam bang job of finishing breaking that thing in for ya'

We could bring a few assorted colors of spray paint and really make that thing pretty too
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