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'94 GT-40, loss of power in gear

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=41300
Printed Date: April-27-2024 at 12:07pm


Topic: '94 GT-40, loss of power in gear
Posted By: AKhunter
Subject: '94 GT-40, loss of power in gear
Date Posted: June-19-2017 at 6:54am
After reinstalling the engine/transmission on my ski nautique (95-96?) from a tow pylon repair, I took it out for a test run. Test run was great except for a throttle cable was routed wrong, and some occasional weird tach. readings (old problem). When I came off step at the end of the test run, the throttle stuck and I accidentally shifted into neutral from approx. 2,000 RPM. It was a bit of a clunk going into neutral. Immediately after rerouting the cable, I attempted to start, and an old recurring ignition problem reared its head. Maybe coincidence of timing, maybe not? After new plugs, spark plug wires, distributor, coil, and a careful timing job, it runs great in neutral all the way up to full RPM. But when I try to shift into forward or reverse, the engine attempts to stall. It has no power, and does not accelerate properly. Full throttle gives me roughly 1,500 RPM in gear. Engine seems to "bog down" badly when in gear.
The engine was completely rebuilt 45 hours/ 3 oil changes/ 2 years ago.
Did I just kill my transmission?
Help!?



Replies:
Posted By: 8122pbrainard
Date Posted: June-19-2017 at 7:04am
Keenan,
Pull the plugs and turn the engine over with a breaker bar on the crank/balancer bolt. Listen and feel for scraping in the bell housing. There's a chance the damper was blown. Also, does the engine still have the Pro Tech ignition? You did mention it has a "distributor".

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Posted By: AKhunter
Date Posted: June-19-2017 at 7:16am
That's the spring loaded triangular plate that's bolted to the flywheel/starter ring gear inside the bellhousing? He's fine, I was looking at him earlier this evening (actually, I guess that's last night?). I'm not sure about the pro tech ignition you referenced? Please explain?


Posted By: 8122pbrainard
Date Posted: June-19-2017 at 8:42am
Keenan,
I'll try to find some pictures of the Pro Tech but basically it was used between 91 and 94. It's prone to failure and many have had to retrofit back to a standard ignition system. In later years with fuel injection, the retrofit also includes going back to a carb. The ignition system uses 4 coil packs which are rectangular boxes mounted on the aft end of the engine. Then instead of a distributor, there's a trigger pickup. Where do you plug wires come from? If the coil packs, then it's a Pro Tech.

I mention the Pro Tech since you mentioned the recurring ignition problem.

Yes, the damper is the spring loaded plate on the flywheel. BTW, if it's original, you may want to consider replacing it. They do wear out and they also are under $100.00.

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Posted By: JPASS
Date Posted: June-19-2017 at 8:43am
Originally posted by AKhunter AKhunter wrote:

I'm not sure about the pro tech ignition you referenced? Please explain?


The ProTec ignition is the factory supplied ignition system that has been known to fail. You can tell if you have it by looking at the "distributor" If it has spark plug wires coming off of it, then it's not the ProTec. If it has a flat black cap and a set of coil packs behind the carburetor, then you have the ProTec set-up.

Protec system here:






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'92 Correctcraft Ski Nautique


Posted By: 8122pbrainard
Date Posted: June-19-2017 at 8:51am
Keenan,
JP beat me to finding the picture while I was searching! Thanks JP.

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Posted By: KENO
Date Posted: June-19-2017 at 9:59am
Originally posted by AKhunter AKhunter wrote:

After new plugs, spark plug wires, distributor, coil, and a careful timing job,


This don't sound like a Pro Tec to me

it seems to me that an engine running at 2000 rpm under load and then being shifted to neutral with the throttle stuck would rev to the moon and you'd be more likely to have engine problems than transmission problems.

The transmission should have handled going into neutral just fine since you're just removing hydraulic pressure from the forward clutch piston


Posted By: 8122pbrainard
Date Posted: June-19-2017 at 10:06am
Originally posted by KENO KENO wrote:

Originally posted by AKhunter AKhunter wrote:

After new plugs, spark plug wires, distributor, coil, and a careful timing job,


This don't sound like a Pro Tec to me

Nor to me ether and the reason I mentioned this but, we have had confusion before! :
Originally posted by 8122pbrainard 8122pbrainard wrote:


Keenan,
Also, does the engine still have the Pro Tech ignition? You did mention it has a "distributor".

Keenan,
How about posting a picture of the engine?

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Posted By: AKhunter
Date Posted: June-19-2017 at 1:59pm
It does not have the Pro-Tech ignition system on it, it's a standard distributor and coil. I'll see if I can get pics of it later today. The fuel is a EFI system. I don't think that's a factor, but I'll throw it out for consideration.
I am the maintenance guy for a kids camp for 2 1/2 years, so I don't have a lot of maintenance history on the boat. My aircraft mechanic mind is telling me that it stinks like a timing advance issue, but I can't figure out how to verify that hunch.
I guess I was pretty tired last night, because I totally forgot to mention the rattly grinding noise that the Xmsn makes when I put it in gear. I cant tell If I'm hearing gear lash that's strongly amplified by the engine running so poorly, or if there's something wrong inside. It rotates quite smoothly and easily by hand, so I'm wondering if it's all ok in there.


Posted By: backfoot100
Date Posted: June-19-2017 at 2:30pm
Look at the title boys. GT40 (if truly a GT40) won't have pro tec.

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When people run down to the lake to see what's making that noise, you've succeeded.



Eddie


Posted By: 8122pbrainard
Date Posted: June-19-2017 at 2:35pm
Keenan,
Rotating the trans by hand really won't tell you much since the clutch packs aren't engaged so you really aren't turning anything except a shaft and bearing.

For the timing issue, get a timing light on it and see if it is advancing. The mechanical advances do rust up and need some maintenance at times.

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Posted By: KENO
Date Posted: June-19-2017 at 2:59pm
Originally posted by backfoot100 backfoot100 wrote:

Look at the title boys. GT40 (if truly a GT40) won't have pro tec.


That's been mentioned already, and depending on where you read it's either a 94,95 or a 96


And for Pete, his distributor doesn't have mechanical advance, the timing is controlled by that newfangled "magic box" called a computer

I'm a little confused what the state of assembly or maybe disassembly is of this right now, since AK was looking at the damper plate and it was good, unless that was right before he put the transmission on the engine


Posted By: 8122pbrainard
Date Posted: June-19-2017 at 4:16pm
Originally posted by KENO KENO wrote:


depending on where you read it's either a 94,95 or a 96


And for Pete, his distributor doesn't have mechanical advance, the timing is controlled by that newfangled "magic box" called a computer

Yes Ken, I too am confused as to the year BUT, if it was a 94 with a Pro Tech and was converted to a distributor, then the mechanical advance would be a concern and the direction I was heading.
Keenan,
We sure need more input from you.

Maybe I should change that "work Pete over" to 2% instead of the 1% of the time?

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Posted By: KENO
Date Posted: June-19-2017 at 4:36pm
I bet we'll agree right about now that we're both 100% or so confused without having anymore info


Posted By: 8122pbrainard
Date Posted: June-19-2017 at 4:59pm
Originally posted by KENO KENO wrote:

I bet we'll agree right about now that we're both 100% or so confused without having anymore info

An absolute yes!!

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Posted By: Gary S
Date Posted: June-19-2017 at 5:05pm
I'm not confused, it's Johnny Cash's Nautique. After he built his Caddy he went to Correct Craft to build boats.

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95 Nautique Super Sport


Posted By: AKhunter
Date Posted: June-19-2017 at 5:25pm
Here are some pics of the engine. It is removed from the boat, however if the consensus is that the problem is in the engine rather than the drivetrain, I can swing the engine back into the boat within a couple of hours. Is there any other information that you guys need that I'm missing?





Posted By: AKhunter
Date Posted: June-19-2017 at 5:32pm
Originally posted by Gary S Gary S wrote:

I'm not confused, it's Johnny Cash's Nautique. After he built his Caddy he went to Correct Craft to build boats.

All jesting aside, it's actually a boat that was donated by Correct Craft to the camp. I'm not sure if it was donated new, or if it was a demo/show model.


Posted By: 8122pbrainard
Date Posted: June-19-2017 at 8:47pm
Keenan,
Before you go to the trouble of dropping the engine back in, why don't you remove the spark plugs and belts. Then with a breaker bar on the harmonic balance bolt turn the engine over. Ken's idea of the high rev damaging something is sound. See if there are any tight spots when turning the rotating assembly. Just a "shot in the dark"?

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Posted By: AKhunter
Date Posted: June-20-2017 at 1:05am
Originally posted by 8122pbrainard 8122pbrainard wrote:

Keenan,
Before you go to the trouble of dropping the engine back in, why don't you remove the spark plugs and belts. Then with a breaker bar on the harmonic balance bolt turn the engine over. Ken's idea of the high rev damaging something is sound. See if there are any tight spots when turning the rotating assembly. Just a "shot in the dark"?

I've already done that and found nothing of note. It has no tight spots or noticeably loose spots either.


Posted By: AKhunter
Date Posted: June-20-2017 at 1:12am
I talked to the dealer today, and he was able to tell me that the hull is from July of '97 based off of the serial number. I still don't know the engine MFG date, but the dealer thinks it's probably a '94 or '95, again based off of the serial number.


Posted By: Gary S
Date Posted: June-20-2017 at 1:38am
The engine is not a '94,94's did not have multi-port injection,Not a 95,95's did not have Fuel Control Cells,FCC's- unless retrofitted and also had the intake system from the Ford SVT Lightning like below. Post the last 4 of the serial number of the boat it will be something like this E697 that will tell us which month and model year it was made,if you say the boat is july 97 it's most likely to be a 96 or 97 engine



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Posted By: AKhunter
Date Posted: June-20-2017 at 1:54am
Last 4 of the hull SN: B797


Posted By: Gary S
Date Posted: June-20-2017 at 2:03am
Built in February of 97 as a 1997 model.

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Posted By: tryathlete
Date Posted: June-20-2017 at 7:07am
Gary, I think the GT40 engine has a rev limiter, right?


Posted By: KENO
Date Posted: June-20-2017 at 8:42am
It does have an electronic rev limiter that should have worked even with the sudden unloading of the engine.

He says the engine turns smoothly, the transmission turns smoothly and the damper plate is good and it idles beautifully, but that an old ignition problem popped up again.

Sounds like he thinks the ignition problem is fixed but you put it in gear and it rattles like hell and won't accelerate.

That's what I get from reading things, is there some other big piece of info missing other than confusion about the engine specifics.

I'd probably be looking at the GT 40 manual in the reference section along with the GT 40 troubleshooting thread and checking that all the sensors are hooked up and working.(starting with the throttle position sensor} and that it's firing on all 8 cylinders.

What was the recurring ignition problem that you were having?



Posted By: 8122pbrainard
Date Posted: June-20-2017 at 9:39am
Originally posted by KENO KENO wrote:

I'd probably be looking at the GT 40 manual in the reference section along with the GT 40 troubleshooting thread and checking that all the sensors are hooked up and working.(starting with the throttle position sensor} and that it's firing on all 8 cylinders.

http://www.correctcraftfan.com/forum/forum_posts.asp?TID=25584&title=poor-mans-gt40-diagnosis" rel="nofollow - GT40 troubleshooting thread

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Posted By: AKhunter
Date Posted: June-20-2017 at 2:08pm
Originally posted by KENO KENO wrote:

It does have an electronic rev limiter that should have worked even with the sudden unloading of the engine.

He says the engine turns smoothly, the transmission turns smoothly and the damper plate is good and it idles beautifully, but that an old ignition problem popped up again.

Sounds like he thinks the ignition problem is fixed but you put it in gear and it rattles like hell and won't accelerate.

That's what I get from reading things, is there some other big piece of info missing other than confusion about the engine specifics.

I'd probably be looking at the GT 40 manual in the reference section along with the GT 40 troubleshooting thread and checking that all the sensors are hooked up and working.(starting with the throttle position sensor} and that it's firing on all 8 cylinders.

What was the recurring ignition problem that you were having?


You pretty much nailed it there. When I try to accelerate in gear, it bogs down, and seems to shudder a bit, like its trying to go but just can't.
The ignition problem I was having is that it suddenly starts to miss and run awful. No specific repeatable event leading up to it, one day it just starts to miss really bad to the point that it barely runs. If I replace the coil, plugs, wires, and distributor cap/rotor together it goes away. None of the individual items replaced seem bad when I test them, and I can't seem to pinpoint which it is by replacing one at a time. It pops up every year or two, so I guess maybe I need to just add it to my annual maintenance. I'll reread the troubleshooting thread, and go find that manual and read it too.
Thanks.


Posted By: KENO
Date Posted: June-20-2017 at 2:27pm
Pete aka "the missing link" gave you a link to the thread on troubleshooting the GT-40 a post or 2 back

I really don't think you hurt the transmission or the damper plate and just have an ignition problem making it run lousy under load and that's whats causing the gear lash rattle in the transmission.

That's my guess from a long, long ways away from Alaska


Posted By: Bri892001
Date Posted: June-20-2017 at 2:39pm
Wondering if it's something in or around the distributor. I'd check to see if you have any kind of excessive wobble or anything like that. You would do that with the cap off and holding onto the rotor portion and trying to move it around.

It seems funny that it's going through caps and rotors that fast, wondering if the act of replacing those items is brushing up against something that is loose/faulty and temporarily fixing it.


Posted By: AKhunter
Date Posted: June-20-2017 at 2:54pm
Originally posted by Bri892001 Bri892001 wrote:

Wondering if it's something in or around the distributor. I'd check to see if you have any kind of excessive wobble or anything like that. You would do that with the cap off and holding onto the rotor portion and trying to move it around.

It seems funny that it's going through caps and rotors that fast, wondering if the act of replacing those items is brushing up against something that is loose/faulty and temporarily fixing it.

I'll check. This time I replaced the entire distributor because due to two striped out threaded holes. I figured that was easier than trying to install 8-32 helicoils.
Are you suggesting something in the engine's timing gears, or something outside the engine case?


Posted By: Bri892001
Date Posted: June-20-2017 at 3:21pm
I was thinking the distributor itself, but since you already replaced that, that covers that idea.

When an engine is under load, any thing that is "shaky" as far as electrical connections related to the ignition is more apt to act up.

Of course, any fuel starve problem, timing problem or vacuum leak is also more likely to cause problems under load.


Posted By: fgroce
Date Posted: June-20-2017 at 9:05pm
Don't forget the module on the heat sink, they were prone to failure. May have been why the put it on a heat sink instead of the distributor like Ford did. If he is getting a skip scan the computer for codes, KOEO and KOER and there are several other balance test you can run to narrow down the skip.

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88 Ski Nautique
For 28 years
Now 2002 Ski Nautique


Posted By: AKhunter
Date Posted: June-21-2017 at 3:46am
I got the engine back in and did a test run. Almost the same as before, but after adjusting the idle up a bit, the stalling on shift is cured. On a whim, I powered it up in reverse and I get full power?!! This new piece of info seems to point back to the transmission again?


Posted By: 8122pbrainard
Date Posted: June-21-2017 at 6:40am
Originally posted by AKhunter AKhunter wrote:

On a whim, I powered it up in reverse and I get full power?!! This new piece of info seems to point back to the transmission again?

Keenan,
Could you expound on the above? Sorry, I'm not following what's happening.

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Posted By: AKhunter
Date Posted: June-21-2017 at 4:17pm
Originally posted by 8122pbrainard 8122pbrainard wrote:

Originally posted by AKhunter AKhunter wrote:

On a whim, I powered it up in reverse and I get full power?!! This new piece of info seems to point back to the transmission again?

Keenan,
Could you expound on the above? Sorry, I'm not following what's happening.

At the beginning of the thread, my engine was pulled, and transmission removed from the engine. I thought I was chasing a timing or timing advance issue. Everything I could see seemed to point towards timing advance issue. I had not pulled codes properly per the Pro-Boss GT-40 service manual before removing the engine because I hadn't found the manual prior to removing it. Another factor in my decision to follow the timing issue is that trying to get my current transmission overhauled would take close to a month considering my location. That would make the boat unusable for the rest of the camp season. I guess I was hoping that I might find an answer in the engine that I could repair before the end of the camping season. So, I reinstalled it all, checked my timing, and adjusted my idle up. I was about to start pulling codes, when I decided to try reverse. That's something I should have done before I pulled the engine in the first place. Reverse worked fine, plenty of power, and the engine ran great up to 3,000 RPM. I couldn't run higher than that because the prop tries to cavitate if I run it higher.

If it runs well in reverse (yes, I was in the lake when I ran it), I know that the engine is developing torque. The spark advance seems fine, I watched it with a timing light as it ran, both in neutral and reverse. In forward, the engine struggles so much I can't get a good reading on it. It seems to me that the fact that it runs well in reverse and neutral, under torque and unloaded says that the engine is fine, and the problem is in the transmission. The transmission manual (PCM 40A) says that it has separate clutch packs for forward and reverse. I'm wondering if I damaged the forward clutch when I slammed it into neutral from 2,000 RPM. While the engine was out, I did check the prop shaft and bearings. They spun smoothly with no sign of wobble or binding, so I'm pretty sure I can say that there is no problem back there.

What do you all think? Am I on the right track, or am I following a rabbit trail?


Posted By: Dreaming
Date Posted: June-21-2017 at 4:55pm
out on a limb here... Since this is a GT-40, I am not sure how the interface between engine RPM and Fuel delivery is made, but here is something to check anyway....YMMV

- If the engine is in neutral, and revs fine, but struggles under load, I too would have assumed timing advance originally.   Since you feel that you have vetted this angle, I would be looking into fuel delivery.   It seems to me that if the engine was getting a lean mixture of fuel, under load, it would cause a problem similar to what you might be experiencing. A lean detonation (or a malfunctioning knock sensor) could cause the ECM to retard the timing severely to protect the engine components... Sensors mustplay a big roll in the fuel delivery process, as would the ECM, which is known to have problems in these boats.   There does seem to be a work around for the ECM, so if that is the issue, you'll be on the cutting edge of the fix.

    The transmission seems like a reach to me.   Is there any way you could swap out a transmisision, either throw yours in a different boat, or pull in a known good one and see if the problem persists? that would focus your troubleshooting or give you a good idea of where to go next.


Posted By: AKhunter
Date Posted: June-21-2017 at 5:59pm
Originally posted by Dreaming Dreaming wrote:

out on a limb here... Since this is a GT-40, I am not sure how the interface between engine RPM and Fuel delivery is made, but here is something to check anyway....YMMV

- If the engine is in neutral, and revs fine, but struggles under load, I too would have assumed timing advance originally.   Since you feel that you have vetted this angle, I would be looking into fuel delivery.   It seems to me that if the engine was getting a lean mixture of fuel, under load, it would cause a problem similar to what you might be experiencing. A lean detonation (or a malfunctioning knock sensor) could cause the ECM to retard the timing severely to protect the engine components... Sensors mustplay a big roll in the fuel delivery process, as would the ECM, which is known to have problems in these boats.   There does seem to be a work around for the ECM, so if that is the issue, you'll be on the cutting edge of the fix.

    The transmission seems like a reach to me.   Is there any way you could swap out a transmisision, either throw yours in a different boat, or pull in a known good one and see if the problem persists? that would focus your troubleshooting or give you a good idea of where to go next.

I can check that, but how could I be getting normal power in reverse, but not forward if that's the issue?


Posted By: KENO
Date Posted: June-21-2017 at 6:05pm
Dreaming He says it runs under load in the water in reverse. He quit at 3000 rpm due to the prop.

What I'm wondering is how you put it into neutral at 2000 rpm originally without having some kind of "war of the cables and linkages"

With a single lever Morse that's a hard thing to do without breaking or bending something.

Do both cables extend and retract smoothly the way they should?

We're not gonna see you on an episode of Yukon Men sometime soon are we?


Posted By: AKhunter
Date Posted: June-21-2017 at 6:21pm
Originally posted by KENO KENO wrote:

Dreaming He says it runs under load in the water in reverse. He quit at 3000 rpm due to the prop.

What I'm wondering is how you put it into neutral at 2000 rpm originally without having some kind of "war of the cables and linkages"

With a single lever Morse that's a hard thing to do without breaking or bending something.

Do both cables extend and retract smoothly the way they should?

We're not gonna see you on an episode of Yukon Men sometime soon are we?

I'm not sure why the cables didn't fight each other? They didn't seem to, I can't find anything out of place/bent/broken in the cables and linkages, and both run smoothly. There isn't much travel of the throttle cable between 2,000 and idle and there is a bit of slop in the end of my throttle cable/throttle lever balljoint. It was the throttle lever that stuck, and as soon as I moved the offending cable, the lever snapped back to idle.


Posted By: Dreaming
Date Posted: June-21-2017 at 8:57pm
Originally posted by KENO KENO wrote:

Dreaming He says it runs under load in the water in reverse. He quit at 3000 rpm due to the prop.[/IMG]


fine, go ahead and cut off my limb

I saw that he was running it in reverse, but missed the 3000 RPM issue. Are the Trans's geared different in reverse?   Not that it would solve the problem, but the motor loading would be different


Posted By: AKhunter
Date Posted: June-21-2017 at 9:45pm
Originally posted by Dreaming Dreaming wrote:

Originally posted by KENO KENO wrote:

Dreaming He says it runs under load in the water in reverse. He quit at 3000 rpm due to the prop.[/IMG]


fine, go ahead and cut off my limb

I saw that he was running it in reverse, but missed the 3000 RPM issue. Are the Trans's geared different in reverse?   Not that it would solve the problem, but the motor loading would be different

Should I be worried about cavatating @ 3,000 RPM in reverse? I thought that would be normal. 3,000 RPM in reverse moves the boat rather fast and plows up a large wake. I was worried I'd swamp the boat with the wake if i pushed it much harder. I can't imagine a time when I'd want more thrust in reverse.


Posted By: KENO
Date Posted: June-21-2017 at 9:52pm
3000 in reverse means it'll handle some load.

The 1.23 to 1 PCM's have a reverse ratio of about 1.8 to 1 so yes it's different but I don't think that should change engine loading enough to let it run in reverse but not want to move it at all in forward.


Posted By: AKhunter
Date Posted: June-21-2017 at 10:09pm
Originally posted by KENO KENO wrote:

3000 in reverse means it'll handle some load.

The 1.23 to 1 PCM's have a reverse ratio of about 1.8 to 1 so yes it's different but I don't think that should change engine loading enough to let it run in reverse but not want to move it at all in forward.

Is there any way to test the transmission before I before I drop 2.5k into a new or rebuilt one? I don't want to find out afterward that it wasn't the problem after all.


Posted By: 8122pbrainard
Date Posted: June-21-2017 at 11:06pm
Originally posted by AKhunter AKhunter wrote:


Is there any way to test the transmission before I before I drop 2.5k into a new or rebuilt one? I don't want to find out afterward that it wasn't the problem after all.

Eric of FFM would chuck up the input shaft on his rebuilds in his engine lathe for testing.

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Posted By: KENO
Date Posted: June-22-2017 at 8:53am
If you want to spin the transmission in forward why not run the boat on the trailer either disconnect the shaft from the transmission or get the cutlass bearing good and wet with a hose

I think I'd disconnect the shaft if you're gonna do this for a while so you don't accidentally run the shaft with the cutlass dry (and you won't chop up any stray animals or people that get too close to the prop}

Then supply cooling water to the engine/trans cooler with a hose and run it.

You can shift from neutral to forward/reverse and see what happens with no load on the engine/transmission. Maybe everything spins freely with no noise/problems and you can rev it up or maybe it will spit and sputter and make funny noises and not want to rev up at all.

Basically just like spinning it on a test stand with no load

You could also shift the transmission with the cable disconnected and rev the engine with the throttle cable disconnected to rule out linkage/cable issues.



Posted By: SNobsessed
Date Posted: June-22-2017 at 10:07am
If the tranny is binding/dragging, wouldn't it get really hot really fast?

Maybe measure temp rise for a test.

I vote for the binding shifter/cable theory, since we already know if failed to start with.

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Posted By: KENO
Date Posted: June-26-2017 at 11:30pm
I'm wondering what's been happening with this mystery.


Posted By: AKhunter
Date Posted: June-28-2017 at 2:27pm
Originally posted by KENO KENO wrote:

I'm wondering what's been happening with this mystery.

I'm waiting for a new transmission. When I finally got the tranny oil plug out (Snap-On easy out and a 3/8 breaker bar) I found a fair bit of superfine non-magnetic powdered metal in the oil. It kinda looked like a maroon metallic paint. I'm about 98% sure that this is the problem. This winter I'll probably rebuild this tranny for a spare or sell- but mostly just to satisfy my curiosity. The new one is a conversion kit to a newer modle, I think the transmission shop said that it was a PCM-80 A?


Posted By: KENO
Date Posted: June-28-2017 at 2:49pm
I guess I'm not wondering anymore., on second thought I guess I'm wondering how going to neutral damaged it but maybe you can figure that out if you take it apart.

Sounds like you're describing clutch plate material in the fluid

Give an update when the new one is in


Posted By: 8122pbrainard
Date Posted: June-28-2017 at 2:53pm
Originally posted by KENO KENO wrote:

I guess I'm not wondering anymore., on second thought I guess I'm wondering how going to neutral damaged it but maybe you can figure that out if you take it apart.

Sounds like you're describing clutch plate material in the fluid


I have a feeling it when past neutral into reverse?

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Posted By: AKhunter
Date Posted: June-28-2017 at 3:15pm
Originally posted by KENO KENO wrote:

I guess I'm not wondering anymore., on second thought I guess I'm wondering how going to neutral damaged it but maybe you can figure that out if you take it apart.

Sounds like you're describing clutch plate material in the fluid

Give an update when the new one is in

It might be clutch plate powder, but I have my doubts. When I separate the powder in a filter it has a yellow hue to it like its brass or bronze. Harbor Marine's transmission guy says that there are bushings made from both in this unit. I'll keep you guys posted, and if I remember, maybe I'll even resurrect this thread when I split the old tranny to rebuild. Another bit of interesting info, I asked about the maintenance history of this boat, and I got funny looks and questions about where the drain plug was located when I asked about transmission oil changes. I think the oil is still whatever Correct Craft put in it in '97


Posted By: KENO
Date Posted: June-28-2017 at 3:45pm
You've also got sintered bronze clutch plates Half of the fwd plates are steel and the other half are sintered bronze.

When they slip enough the wear particles end up in the fluid


Posted By: Duane in Indy
Date Posted: June-28-2017 at 10:25pm
I have to go with KENO on this one.   Bushings in the tailshaft are very unlikely to have worn out.   Forward clutch plates.

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Posted By: AKhunter
Date Posted: June-28-2017 at 11:48pm
Originally posted by KENO KENO wrote:

You've also got sintered bronze clutch plates Half of the fwd plates are steel and the other half are sintered bronze.

When they slip enough the wear particles end up in the fluid

Ok, I didn't know that's how they built the clutch plates. So my "rebuild" of that transmission may be as simple as replacing the clutch pads or assemblies and flush/replace 10 year old ATF fluid? I guess I won't know until I start tearing it apart.


Posted By: SHOBRONCO
Date Posted: August-14-2017 at 4:13pm
My boat is having the same problem, wonder if the new transmission fixed the problem?


Posted By: KENO
Date Posted: August-14-2017 at 7:03pm
If I was you I'd start a new thread describing your symptoms because AKHunter hasn't logged in since June 30th.and not all loss of power problems turn out like his


Posted By: Dreaming
Date Posted: August-14-2017 at 7:04pm
Hi SHOBRONCO,
   Not going to get many responses jumping on to an old resolved thread, but we'd be happy to help.   Welcome to the site, start a new thread, tell us about your boat, what engine and configuration, year etc, and what symptoms you're having.    we can walk you through the process of troubleshooting so you don't drop 2k on a trans and have the same issue as when you started.    these boats are pretty simple creatures, so some troubleshooting usually will help point out the real issue.


Posted By: Dreaming
Date Posted: August-14-2017 at 7:12pm
KENO - must be faster on the draw than me today


Posted By: SHOBRONCO
Date Posted: August-14-2017 at 9:25pm
Thanks Keno and Dreaming. Started new thread.



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