2005 Volvo SX drive - CLUNK!

[dallasag]

I have a 2005 Four Winns 180 with a Volvo 4.3 with the SX drive. When I shift the boat into drive or reverse, there is a noticeable clunk.

I have actually only owned the boat for a couple months. When I first bought the boat, the clunk was present but the boat was idling high. I reduced the idle and that fixed the clunking. Well, its back, and its not the idle - I have it set to idle at about 650-700 and about 600 in forward gear (assuming my tach on the boat is accurate).

I have tried reducing the idle screw. It helps but does not totally elimnate the clunk. The problem is that when I reduce the idle screw, the boat runs really rough and I have a California Emissions carb that has metal covers over the idle mixture screws (appears to require total disasembly of the carb - over my head).

The prior owner changed the sterndrive lube, but I do not believe that he ever had the drive removed and services. I was hoping to wait until the end of the season to have the drive serviced.

Anyone have any ideas of how I could troubleshoot this issue without taking the boat in for service? Assuming it might be a problem inside the drive unit, any idea what it could be and what the damage (both to the drive and the wallet) could be to fix?

Thanks in advance.

 

[Don S]

Re: 2005 Volvo SX drive - CLUNK!

The high idle BEFORE you bought the boat, is probably the cause of your problems now and has already caused the damage.
Disassembly, inspection, part replacement and reshimming (if necessary) is the only option I can suggest.

 

[dallasag]

Re: 2005 Volvo SX drive - CLUNK!

Thanks for the help Don. Is this the type of thing that is complex enough to warrant taking it to the dealership instead of the marina boat mechanic?

 

[Don S]

Re: 2005 Volvo SX drive - CLUNK!

Thanks for the help Don. Is this the type of thing that is complex enough to warrant taking it to the dealership instead of the marina boat mechanic?

Without the proper equipment (Special tools) the job is almost impossible, but can be done in about 100 hours of labor using the trial an error method.
Which way would you want your drive fixed. Ones that know, or ones that can fix it eventually?

 

[mikeneal]

Re: 2005 Volvo SX drive - CLUNK!

I agree with Don S (always do) and there is 99.99% chance the high idle effected the shimming of the drive gears but one thing you might check is the prop hub. Some props have inserts to be used with different drive prop shafts. If your prop has such an insert I have seen the hubs get worn and sloppy and cause a nasty clunk. Maybe , just maybe the high idle beat on the prop hub. Cross your fingers, it is at least worth a lookie.

 

[gadget73]

Re: 2005 Volvo SX drive - CLUNK!

How high is "high" though? If we're talking 700 rpm vs 650, its probably not the end of the world. If we're talking 1000 rpm, then yeah thats bad.