Motor shakes violently, sometimes.....

[Redhook98]

Here is a strange one.... I have a 2004 Monterey 265CR with a Volvo 5.7Gxi and DP-S drive. I bought it last year and never had a problem. This year, I started it up on land when de-winterizing and after a minute or so, turned the wheel just a bit, and the motor started to shake violently. Turned it off, started back up, and no problems. Put it in the water and found I had a gimble bearing that sounded bad. Yanked it back out, had the bearing and bellows replaced, everything re-aligned (saw them do it).

Engines still periodically shakes violently though. U-joints were good, gimble bearing is good. Only does this when in close area manuevering with slight turns of the wheel. Turning back stops it right away, then I am free to turn again..... Does not happen when accelerating or higher RPM's. Only at idle and lower RPMs (i.e. docking, etc).

Any ideas out there? Have not hit anything, no damage to speak of anywhere... Only 200 hours on system.......

Hmmmmmmmm........

 

[Coors]

Re: Motor shakes violently, sometimes.....

u-joints look and feel when good when bad.

 

[Don S]

Re: Motor shakes violently, sometimes.....

You can get that shaking if there is air in your power steering system. Have you checked the level of the PS fluid?
When it gets air in it like that, be sure the PS fluid level is ok, then (with the engine off) turn the steering lock to lock 3 or 4 times, and recheck the fluid. Then start the engine. and try it.
Also make sure there is nothing binding the steering cable where it goes into the PS unit. It has to be free to move or it will shake. Even tight bends close to the cylinder can cause problems.

 

[Redhook98]

Re: Motor shakes violently, sometimes.....

u-joints look and feel when good when bad.

U-joints were checked by the mechanics (both Merc and Volvo Cert'd). No noise from the u-joints lock to lock, even hard over at higher RPMs.



Will check the fluid level and for obstructions. It has always made a slight "sliding", rubber-like noise when turning..... Sort of like a dry seal... problem is, there are no seals to lube in the steering that I could find. Sprayed the whole area with WD-40 to test this theory last season... No joy.....

 

[Coors]

Re: Motor shakes violently, sometimes.....

I may get in trouble here, but wd40 only displaces water; You can still find omc triple lube at a johnson/evinrude dealer, which is good mojo

 

[goofinoff]

Re: Motor shakes violently, sometimes.....

You say it shakes when you are at boat ramp, getting ready to dock. Is your trim up? Mine will shake very bad when I set trim up, them when I drop motor down into water, shaking stops. Can anybody tell us if it is normal for drive to shake when trimmed up, turning at slow speeds? Mine is a 1998 Glastron with volvo penta SX outdrive.

 

[gregstukey]

Re: Motor shakes violently, sometimes.....

I'm pretty sure that shaking with the trip up is your U-joints "hyper-extending" and no I dont think that is a good thing. Trimming mostly up is for "trailer-position" and ground clearance and not really meant to be operated with. Trim up maybe 50% for shallow water operation is ok at low RPMs but I'm pretty sure if your feeling a pulse in your steering wheel or outdrive that its the U-joints tweaking out.

 

[Redhook98]

Re: Motor shakes violently, sometimes.....

Sorry I never gave an update to this. It was air in the lines. I have since sold the boat, but wanted to close this out. Thanks all!!