upper bearing failure

[Harryb45]

I have a 1990 evinrude 200 hp , what could cause the lower most bearing to fail there are 2 in a cluster on the top of the crank or is this common in these engines not sure of the amount of hours on it,I have owned it for 7 years and its never been apart.
Any thing I should check for before I reassemble ?
Thanks for any info anyone provides

 

[coolguy147]

Re: upper bearing failure

water.

 

[jonesg]

Re: upper bearing failure

I have a 1990 evinrude 200 hp , what could cause the lower most bearing to fail there are 2 in a cluster on the top of the crank or is this common in these engines not sure of the amount of hours on it,I have owned it for 7 years and its never been apart.
Any thing I should check for before I reassemble ?
Thanks for any info anyone provides

Out of balance flywheel comes to mind, lack of lube too.

 

[clanton]

Re: upper bearing failure

Check the recirculation hoses and check valves. There should be a nipple on the upper and lower main bearing. Reinstall bearing housing with new bolts and loc-tite red. How did you know the bearing is bad?

 

[Harryb45]

Re: upper bearing failure

heard screeching noise and engine just not sounding healthy,
any thing I should check to see if it is getting lubed properly

 

[clanton]

Re: upper bearing failure

What I said in above post. Holler if you need hose diagram.

 

[daselbee]

Re: upper bearing failure

What Clanton said. There is a recirc hose that goes from #6 up to #1, and there is a check valve in that hose, down about an inch from the #6 nipple. If check valve is open both ways, lube cannot get to the upper bearings at #1.

 

[seahorse5]

Re: upper bearing failure

#2 intake manifold provides vacuum to the upper main bearing area which pulls up lube droplets from the lower main thrust bearing. Any water leaking through the lower crankshaft seal, or any debris or water that settles in the thrust bearing area, being the lowest part of the powerhead, travels up the hose and checkvalve between the bearings, which can damage the upper bearing rollers.

If there is debris in the upper cavity, it would be a good idea to pull the port head to check the condition of the #2 piston.

 

[clanton]

Re: upper bearing failure

Diagram of hoses.