volvo questions, long post

[corelock]

I am new here, my name is Robert. I live in Va and do my boating on Smith Mountain Lake. Towables with the kids are the main use of the boat I am buying.
The boat is a 18 ft 1990 Wellcraft Eclipse weighing 2750 lbs with a Volvo AQ131c 230 and I think a 290 drive. 2 years ago the current owner had a bellows leak. THe Bellows and the u-joints were replaced. A vibration started. A second shop looked at the boat and said it was a prop problem, new prop installed. Now to the present. 2 weeks ago the current onwer put the boat in the water for the first time, since getting back from the second shop. Still vibriting, and he hit the prop on the ramp damaging it.
THe boat had 2 yr old gas in it, about 1/2 tank. I filled it with high test. The boat started hard. After running it alittle, it stalled. THere was moisture in the dist. cap. Cleared that boat started easy. The vibration was getting better the more I ran the boat. The vibration is present a idle, and under load. Any ideas on the cause? THe u-joints would seem to make sence as the owner said the vibration was not present until the u-joint replacement. However, as I said the more its run the less it vibrates.
Thank you, Robert

 

[slasmith1]

Re: volvo questions, long post

if the prop and prop shaft are ok the next step is to pull the drive and check all of the following:
1) u-joints
2) gimbal bearing
3) alignment

 

[rucaradio]

Re: volvo questions, long post

I'm pretty sure you've got a setup like mine.. I've got the 131d with the 275 leg.

Assuming you've got a similar setup to mine, there are two bearings on the intermediate shaft (the splined shaft that runs from the motor to the u-joint yolk inside of the bell housing). One is a pilot bearing right next to the engine that the shaft connects with, the other is called the intermediate bearing that holds the shaft true to the bell housing. Both were bad on mine. They will cause vibration and, if they were anything like mine, were VERY in need of being changed.

Take the outdrive off and grab the shaft from outside the boat. If it wiggles up and down or side to side one or both of the bearings are shot.

Bearings and seals will run you around $75 and they're not too difficult to change, but you do have to pull the motor.

 

[corelock]

Re: volvo questions, long post

Thank you both for the quick replys. At this point the boat is 2 hrs away and I will not have time until this weekend to mess with it. Rucaradio, what pitch and size prop do you run? Do you tow, or cruise?

 

[corelock]

Re: volvo questions, long post

More current inforation, the drive is a sp drive. THe prop is a 14 inch 21 pitch. At 4500 rpms I am getting about 30 mph based on gps. Does this sound right? This was with just me on board and a full tank of fuel. THe vibration I mentioned before is getting better but if I try to trim the boat it starts again. Will trimming it in help pick up speed? I am going to get a new prop and was wondering if a 4 blade with a 17 or 19 pitch would do better. I ran a indictor on the prop shaft and it ran true.

 

[captmello]

Re: volvo questions, long post

You should be getting 5000rpm at WOT with that setup. Before you buy a prop you should test your tach against a shop tach to confirm your RPM.

Trimming the drive should help with speed and WOT as well, so check that out before buying a prop.

Like rucaradio stated, it could be those intermediate bearings. Seems like we've all done them. They fail for the same reason as the ujoints. Water.

You'll have to pull your upper to check it out.

Good Luck!!