Caught that funny drivetrain sound, here's a sound clip...

[IDBoating]

I was thinking that too, it may be worth calling PCM or Velvet.

PCM made all three in my boat - engine, transmission, and v-drive. One call does it all!

Hopefully RagBoy will chime in here, although I believe he's already said he hasn't heard anything odd on his boat.

WRT fluids, further research on my part suggests you are supposed to check the transmission level while the engine is running. I haven't done that. The instructions say that the level may read high when the engine isn't running. Perhaps (hopefully?) the fluid is low, reads normal when the engine isn't running, and all I have is a low-fluid condition that is made worse by being at an angle while ballasted.

[IDBoating]

New symptoms.

Got a bonus warm day today and some friends showed up, so we went out to surf. With all the people on the boat it wasn't convenient nor safe to remove the back seat and use the stethoscope to investigate the sound.

However, two new things showed up:

1) The mechanical noise in the audio clip at the top of this thread changed to a definite "squeak". Same timing, still related to prop RPM. It occurs only in forward, never in reverse. I tried reversing when it happened and there was no squeak, but putting it back into forward brought back the squeak.

2) Pulling the throttle lever backwards, into reverse, now causes the engine to rev up well in advance of the propshaft engaging. Previously the engagement behavior was symmetrical: A little lever movement and you could feel the transmission engage, followed by the engine revving up as you continued to move the lever. In other words, it was possible to keep the engine at idle RPM's with the propshaft turning. That's still possible in forward, but no longer in reverse.

I believe this second symptom could simply be a throttle cable misadjustment. But since it happened at the same time as the squeak, I'm suspicious.

I'm not familiar with PCM's transmissions. I'll probably end up taking it to some PCM shop locally, but any ideas in the meantime?

Thanks!

[talltigeguy]

WA,

Fortunately, you are covered under warranty. I think your tranny is about to go crap on you, but it needs a real inspection.

My buddy bought a 2006 24Ve from his brother. The original owner had never owned an inboard boat before and really ended up not using it a lot. He thought it was normal for the engine to rev and then have the tranny kick in. He says he mentioned it once to the dealer, but it was pretty well brushed off. After my buddy bought the boat, (his first inboard also), I was stoked to get out on it. As soon as I got into the boat and felt this abnormal tranny shifting, he started to dig into it. Adjusted the shifting cable and various stuff. Nothing helped and the problem worsened. The tranny had to be replaced, and it was long out of warranty by then, and it was never documented that the problems were starting way back when it was under warranty.

As I mentioned above, I think the noise you were hearing is not pretty, and now you compound it with what is going on now...I hope that you can get this resolved quickly and easily.

[IDBoating]

Fortunately, you are covered under warranty. I think your tranny is about to go crap on you, but it needs a real inspection. As I mentioned above, I think the noise you were hearing is not pretty, and now you compound it with what is going on now...I hope that you can get this resolved quickly and easily.

Me too. I'm not sure what the local PCM dealers do about "on water" problems since none of them are actually at a lake. I'm trying to gather data to help them diagnose things but sometimes dealers just brush off the owner's comments as if he doesn't know anything. Hopefully one of the two PCM shops here will be better than my past experiences with other dealers in this area.

[Ewok]

Me too. I'm not sure what the local PCM dealers do about "on water" problems since none of them are actually at a lake. I'm trying to gather data to help them diagnose things but sometimes dealers just brush off the owner's comments as if he doesn't know anything. Hopefully one of the two PCM shops here will be better than my past experiences with other dealers in this area.

Toblers owns the marina on Hayden lake, thats where they do the water tests.

[wakeatx]

I had the same thing happen to my boat where it would rev before going into gear. Basically the exact same story as Tall mentioned. I had never owned an inboard had been told by the previous owner it was normal. Not until a friend with an inboard drove my boat did I realize there was a problem. My tranny was fried.

[IDBoating]

Ewok, thanks for the tip on Tobler's and Hayden. Might be the answer.

At Dom's suggestion, I dug into the FNR lever. The factory wiring harness runs right next to it and there was a cable that had slipped down into the PPS lever assembly. I worked the throttle lever back and forth, and I don't think it would have affected it, but I've ziptied it back out of the way for good measure. In any case, the PPS and shift cable operations look fine... the shift cable begins moving immediately while the PPS lever is delayed until ~20-30 degrees of throttle lever rotation. That didn't change after I ziptied the wiring.

I checked the Dextron III in the transmission. It's reading a bit over full, but the manual says that's normal when the engine isn't running. The fluid looks clean.

WakeATX, thanks (I think?) for the feedback. I'm hoping my situation isn't as dire... but I'm afraid it may be. The good news is that I'm still within the first year of my three year PCM warranty, and I'd rather get it fixed at the end of a season than have problems at the beginning of the next.

I'm waiting for the winds to die down so I can take the boat out and run some tests, including using a stethoscope to narrow down the noises. We've got gusty winds and whitecaps on the lake at the moment. (Yesterday was dead calm and 95F!)

[IDBoating]

While waiting for the winds to die down, I re-read the manual for the transmission. It says to check the fluid levels by shifting into forward at least once, and then reverse, and then sit in neutral while checking the fluid level.

Doing that, I have fluid exactly at the full mark. So unfortunately it's not just a simple "low fluid" situation. This was at the dock and not above idle RPM's, I don't know if that makes any difference in the measurement.

In the process, I noticed that the "rev before reverse engagement" problem is gone. I don't know if that's related to the ziptied cable (see above), or if it would return after the transmission has been in use for a while. Hopefully I'll know that in a little while.

[IDBoating]

Got some answers...

We took the boat out and ran some tests. Here is what we've learned so far.

1) The mechanical noise in the audio clip is coming from the stuffing box. When the noise is occurring, the slightest pressure on the rubber bellows or the hose clamp on the bellows silences it. I discovered this while searching around with the mechanic's stethoscope, and when I put its probe tip on the hose clamp the sound vanished. Same with the rubber bellows.

I do not see unusual leaking around the stuffing box, and it doesn't seem wildly out of round. There is no visible difference between when the sound is happening and when it isn't.

2) Once that sound started, the transmission's "rev before reverse" came back (?!?). With the tranny and v-drive exposed I could watch the shift lever on the tranny while my wife controlled things. The shift lever moved normally when she put it into reverse, yet the engine revved up well in advance of the propshaft starting to turn.

I should mention that these effects occurred after we started deballasting, and the hull was basically level. I don't think it's related to the list of the boat.

Also, it took about 30-45 minutes before these effects started. I had almost given up because we know it's intermittent and I figured it wasn't going to happen since we were all set up to test it. We were heading home when it finally started.

So... my gut tells me these are related. I'm wondering if something "shifts" in the transmission - perhaps too much axial play on the output side? - which changes something in the stuffing box and also causes reverse to be slow to engage.

Any thoughts?

Edit: Further thought made me realize that the v-drive is between the tranny and the stuffing box, so it's hard to imagine how the former affects the latter. Still, the two things seemed to start at the same time. ?!?!?!??

[dom w. forte]

When the boats on the trailer I would get under it with a flaslight and check in side the stulling box for debree, IMO nothing inside the trans or v box would be effected by moveing the bellows on the shaft.

[IDBoating]

IMO nothing inside the trans or v box would be effected by moveing the bellows on the shaft.

Agreed, I think pressure on the bellows is just stopping the sound that's coming from the stuffing box. I don't think the extremely light pressure I'm talking about could have any impact on the v-drive or tranny.

Then there's the whole separate question of why the tranny reverse behaves like it does. I'm troubled that reverse doesn't engage properly after the transmission has been used for a while. Keep in mind we don't use reverse while out on the water (mostly for docking), so it's not like reverse is getting exercised a lot. What could cause the transmission to be slow to engage in reverse?

Thanks!

[dom w. forte]

The shift cable unclips from the ball on the lever , unclip it and move the shifter and make sure that the lever when fully engauged lines up with the end of the cable, it could be adjusted more towards forward then reverse.

[dom w. forte]

It would be very unusual for reverse to fail, that is the largest clutch pack in the unit, and your noise is in forward.

[IDBoating]

It would be very unusual for reverse to fail, that is the largest clutch pack in the unit, and your noise is in forward.

I think we've proven the noise is from the stuffing box. Even while the noise was happening in real time, I was able to listen to the transmission with a stethoscope and did not hear the noise coming from it. Meanwhile, I could kill the noise instantly by lightly touching the rubber bellows or hose clamp on the stuffing box while doing nothing to the transmission.

So I'm chasing two problems:

1) The sound from the stuffing box. When we pull the boat for the season (in a week or so), I'll inspect the stuffing box from the outside as you recommend for debris or other problems.

2) The slow-to-engage reverse. Next weekend when we're back at the lake, I'll inspect the shift cable as you suggest. However, I should point out that I have very carefully watched the shift cable while Mary was driving and there is ZERO difference between the cable travel when reverse works properly and when it doesn't. On a cold start and for the first 30-45 minutes of operation, the transmission's shift lever rotates to a certain point and reverse engages. Later, the transmission's shift lever rotates to the exact same point and reverse doesn't engage. Pushing it farther causes the engine to start revving (because the PPS has starting moving, I looked per your suggestion) and then reverse "suddenly" engages with a kick and a lurch.

The stuffing box noise is in forward only. The transmission problem is in reverse only. I believe they are separate problems, though it is weird that they seem to occur together.

Thanks!

[Timmy!]

If only you had a Tige dealer near you...