2006 Carver 36 MY port side prop spins in neutral

[Cliffm]

My wife and I are looking at purchasing a 2006 Carver 36 MY with Gas engines, 8.1L Gii-F models. Our recent sea trial last Wednesday displayed a phenomenon. With both engines running but in neutral, the port side engine pop shaft turns, pulling the boat forward if your "idling" at the dock, or spinning in slow circle starboard if both motors running but in neutral.

The dry dock inspection showed starboard prop turned freely (motors off, trans in neutral) while the port side prop was stiff to turn. The initial thought was alignment, but now I'm questioning the transmission clutches.

Would this indicate a bad clutch pack? I know nothing about the internals of these transmissions, assuming they are a Volvo Penta version of Hurth ZF. Are they same for BB vs SB V8's?

There is 217hrs on the port engine but 229hrs on the starboard, does running one engine more than the other damage the transmission?

Is this a common issue? is there a "simple" typical fix?
Does the whole transmission need to be removed to be serviced? or can it be serviced in place?

thanks in advance for your insights and comments as the wife and I are trying to avoid a large money pit issue.

[km1125]

Running one engine vs the other does not impact the transmissions, unless you're talking a a ridiculous amount of time (10,000 hrs vs 1000).

You could either have a valve problem that is pushing some pressure on the clutches or some warped clutches. Do you feel it change significantly when you actually put that engine in FWD? What happens when you put it in reverse? If the RPM on port drops lower than starboard in reverse, that might be a clue that the fwd clutches are still engaged. Running for a long time like that would be bad and overheat the trans, but since you rarely use rev you probably wouldn't have too much of a concern on that.

When it's in neutral and engine off, is there any noticeable drag on the port side vs the starboard side? That might tell you more if it's a warped plate issue.

[bud37]

If you can have the mechanic make sure the shifters are adjusted correctly and see what occurs....lots of trans have some drag but have him make sure.....
Regarding your money pit question.......considering what you have come across already, what do you think at this point ?

[Viper]

I agree with all the above. There are a couple of things that can cause this. This is something you want to get checked by someone who knows transmissions. You may even want to place a call to the manufacturer. It may be a minor transmission creep now but could end up a major failure in the near future. Having said that, I've seen this go on for years in some boats and they're still in operation. Like anything else, might last for 10 minutes, ten days, or ten years.

[Cliffm]

Hatton Marine in Seattle is authorized ZF trans service center. I spoke with Gunnar Hatton, diagnosing out trans symptoms.

Warped clutch pack steel plates, will need R&R to operate correctly. $2290.00 USD for complete trans, at FredWarner1.net, best price I was able to find.

Hatton Marine quoted same trans price, plus install, totaling $4260.00 USD

[bud37]

Thanks for posting, hope it goes smooth...

[RGrew176]

Since you are getting one of the transmissions repaired I would consider at least having the trans fluid in the other transmission flushed and changed. When I had my port transmission rebuilt on my 3007 I had the mechanic change the fluid in the other one. I now know that both transmissions had new fluid put in in 2017. I plan to change the fluid every 5 years.

[390Express]

Source of the post Since you are getting one of the transmissions repaired I would consider at least having the trans fluid in the other transmission flushed and changed. When I had my port transmission rebuilt on my 3007 I had the mechanic change the fluid in the other one. I now know that both transmissions had new fluid put in in 2017. I plan to change the fluid every 5 years.

5 years seems like a long time to me. I generally do mine seasonally, if nothing else, to get the condensation out. I don't know if that is excessive, I boat around 60-100 hours per summer, but for less than $20 or so per side, seems well worth it.