'85 115hp OMC Upper Crank Bearing

[Auxlarry]

Hi Everyone!

Had an interesting problem occur today while out on the water. The engine was running great when I started noticing it cutting out. As I throttled down it felt like I lost fire on at least one or two cylinders and I noticed a strange ting ting noise from under the hood. I was close to the ramp so I just pulled the boat out and headed home.
Upon inspection of the engine I found the ting ting noise coming from under the flywheel, pulled the flywheel and noticed some play in the upper crank and saw some signs of the flywheel scraping the stator.
I pulled the upper crankcase head and the roller bearings are wet, rusty and rough. The crank looks okay but I will have to use my calipers on it to make sure, it has what appears to be water markings on it and total lack of lubrication?
How do the upper end bearings get lubricated? And where shoud I go to find out why I have water in this area?

Your help is always appreciated!

Larry

 

[Auxlarry]

Re: '85 115hp OMC Upper Crank Bearing

Add on to the previous message! '85 115hp V4 xflow model 2BBL

Can't seem to find a bearing cross over number for this upper roller bearing (Torrington AJ47495). Can anyone supply? BRP site only lists the upper crankcase head with the bearing??????

Thanks, Larry

 

[nymack66]

Re: '85 115hp OMC Upper Crank Bearing

I found an old post...The bearing can be purchased at most companies that specialize in bearings only. It can also be purchased at "Precision Mfg & Sales" in Clearwater, Fl (1-800-237-5947), their part #495.
Just make sure that it is installed properly ie depth, oil passage, etc.

Also try http://www.promarineusaonline.com/ you will be better off calling the 800 number ...

 

[emdsapmgr]

Re: '85 115hp OMC Upper Crank Bearing

That's a pretty stout bearing. Usually pretty low failure rates. That bearing can fail due to rust for a couple of different reasons. 1. You could have water in the bottom of the remote oil tank. 2. You could have water in the fuel. As you run the engine, that water will get distributed throughout the engine. If the engine sits for a long period of time (like over the winter) the water will damage/pit that bearing. You may see other signs of rust in the block. If you can find a new bearing only-go for it. Last time I looked for one for a V6, (a Torrington bearing) every source told me the bearing was proprietary and could not be sold to other than the original manufacturer. I bought a used bearing with head from a marine salvage outfit.

 

[Auxlarry]

Re: '85 115hp OMC Upper Crank Bearing

I agree, the upper bearing is a very stout double row roller bearing but mine is now toast. I finally located one at http://outboardparts.com/omc/mall/omcupercrankbrng2.htm in case anyone here needs to find one also and I plan on calling the place in Clearwater this morning since I am located in central Fl.
I did have some water in the fuel issues earlier this year that caused me some running issues but have since pulled the fuel tank and had it cleaned and replaced the rest of the fuel components, rebuilt the carbs and have run about 250 hours since then. I have noticed the past couple of weeks that the engine seemed to lack a little power especially during heavy throttle.
Since the top seal was shot along with the bearing I guess I can assume that I was sucking air into the top side of the engine since my top plugs looked different than the lower plugs?

Thanks for the help and I always appreciate this forum!

Larry

 

[Auxlarry]

Re: '85 115hp OMC Upper Crank Bearing

Okay, I got all the parts ordered today and I have a question?

The supplier recommends that the bearing housing be heated to allow the old bearing to fall out and then the new bearing installed, sounds good to me but if I use an oven what temp should I heat to? Or, can I use an industrial heat gun and just heat it evenly?

 

[Auxlarry]

Re: '85 115hp OMC Upper Crank Bearing

Just to let everyone know, this job was a piece of cake! Heated the aluminum housing up with a heat gun and with just a very light tap on the old bearing with a brass drift it fell right out. The new bearing slide right in after a parts clean up and a reheat.