bearing help needed!

[surfted]

I'm about to check the bearings in my motor. But how can I remove them in a good way without destroying them?

And how do I know if they are bad or not?

Thanks /T

[WillJames]

Strip the motor down to where it is just the case and bearings. Heat it up in a taaster oven or oven to 325 or so. The bearings should practically fall our with very little help. You can also use this method to reinstall them. They go right in when the case is hot.

HTH,

[DavidH]

Put some butter and cinnamon on the case and it will smell nice while heating up <G>. Just kidding.

Will is correct, about 15 minutes in the oven at 350. Use an oven mitt to handle the case. Pop the back of the case on an object and the inner bearing should fall right out.


David

[surfted]

It worked very well!! Thanks!

I have one more question..
Do the bearings feel notchy when they are dry from oil?
I can't really decide if the bearings are allright.

Is there a good way to test the bearings?

the spin freely but is not that smooth.

/T

[Hotshot Charlie]

I think that if the bearings feel notchy, replace them. Someone else might chime in?

[WayneBrown]

oh yeah, notchy, chattery, or feels like sand is bad...anything other than completely smooth is a garbage bearing.
Oil won't smooth them out at 15,000 RPM....

[Russ McC]

T

Now that you are not going to reinstall that old bearing, (why would any one after going to the trouble of removing it) Look further by removing the cage and roll all the balls to one side then push the inner race out with your finger, catch all the balls and inspect each one as well as the races. You may find moderate to extreme damage on both the balls and the races. It’s the rear (big) bearing that goes bad so don’t bother checking the front bearing but do replace them both.

So why did you bother taking the engine apart any way? Just for the sake of checking? You can definitely hear when your engine bearings are going bad so I don’t fix it tell it’s broke. On the 60/90 engines the bearings will last me 60 to 90 gallons of fuel after that I just toss the engine for a new one. OS 50s have been a different story, I have seen these be defective out of the box. I haven’t herd much about this problem lately so they must have resolved it.

[rob_jones]

A tip when putting the bearings back in: It is critical that the rear bearing be installed correctly.

First, put the new bearing on the crankshaft and slide it all the way on. It may be a very tight fit, so be careful not to damage it by applying too much force on the outer race. Then, the easiest way to get it back in the engine and aligned properly is to heat the case back up, then hold it so the front is pointed straight down and you are looking at the back of then engine where the backplate normally is. Now, with the case hot, just drop the crank shaft (with bearing on it) into place in the engine. I usually tap it with a wooden dowel just to be sure it's fully seated. Let the engine cool and you're done! The bearing will be fully seated and properly aligned. :D

[WillJames]

Cool tips guys.

I am curious to know how the case did with the butter and cinimin on it. :D great idea David!!

[WayneBrown]

You could always place the crank in the freezer to shrink it, then place the bearing on the shaft. Freeze the crank/bearing assembly and it should also drop into a room temperature block.