Symtom of Gimbal bearing failure on 5.7 Merc Bravo II

[jerryb1]

I think this forum is great and have learned alot of information from it. I also learned not to ask too many questions in one post as only one or two get answered(understandable).
In a previous post I mentioned my drive resevoir requires topping off after about 5 hrs of operation. Now I hear an occasional squeal in both nuetral and in gear that lasts for a second or two then stops. 10-20 seconds later it happens again. The boat is in the water and the ramp is about a quarter mile away. If it's the gimbal bearing, (don't know if that is it) , should I have it towed or drive it to the ramp to take it out and pull the drive. If the gimbal bearing is bad would it be a steady noise or intermittent like I have.?
Thanks

 

[Bt Doctur]

Re: Symtom of Gimbal bearing failure on 5.7 Merc Bravo II

what condition was the bearing in when you removed the drive for service in the spring BEFORE LAUNCH

 

[Don S]

Re: Symtom of Gimbal bearing failure on 5.7 Merc Bravo II

You need to open the engine hatch, get down next to the engine and have someone start it for you. You now have a few second to listen and see if the squeal is coming from the front or the back of the engine.

Could be nothing more than a loose belt.

 

[sharkin95]

Re: Symtom of Gimbal bearing failure on 5.7 Merc Bravo II

gimball bearings usually don't Squeal when they go they Growwl and vibrate when turning left or right.might be a belt, alternator bearings,power steering pump.

 

[jerryb1]

Re: Symtom of Gimbal bearing failure on 5.7 Merc Bravo II

i will not get to the boat until this coming weekend, but i know it's not a belt or anything from the front of the engine. It doesn't seem to happen on turns so maybe it's not the gimbal bearing. The loss of small amounts of drive oil on a consistent basis makes me think it's a drive issue. What failures would cause drive oil to get into the bilge area on Bravo II?

 

[Don S]

Re: Symtom of Gimbal bearing failure on 5.7 Merc Bravo II

Pull the drive and see if there is gear lube in the bellows, and also check the gimbal bearing and ujoints while in there.

 

[jerryb1]

Re: Symtom of Gimbal bearing failure on 5.7 Merc Bravo II

Thanks Don,
I will do that and expect to find drive oil in the bellows, since its ends up in the bilge. What can I expect the cause of that to be?
Thanks

 

[Grub54891]

Re: Symtom of Gimbal bearing failure on 5.7 Merc Bravo II

The seal on the upper that goes into the bellows,drain the unit,off the boat, and pressure check it,it will leak if the seals are bad.If the oil is milky when removing it you have a seal leaking somewhere in the lower.I've found the shift shaft seal in the most common seal to go but make sure the rest are good also. Prop shafts like to get fish line wrapped around them and take out the seal too. Oh yeah, pressure check at 15 lbs, there is a vacume check also but I don't rember the value. Sometimes they leak water in when cooling down that is what the vacume test checks. Good luck!
Grub

 

[jerryb1]

Re: Symtom of Gimbal bearing failure on 5.7 Merc Bravo II

Thanks Don S. You're the man!Actually thanks to all for the responses as they were all helpful. I'm happy to say that I didn't have to pull the boat out of the water. I took off the engine hatch, started it up, and as clear as day, it was the water circulating pump bearing grinding away. It was so bad that the wheel actually started to wabble when I reved the engine. A $100 for a new pump(West Marine actually had it in stock)and a couple of hours work and all was fixed. I'm surprised it wasn't squirting water out but it wasnt.
As far as the drive oil resevoir being low, i took it for a 40 minute drive and it was still at the full mark from the last time I topped it off.