tigil

Hi all, it the first time I try to remove the crankshaft but nothing want to move.
I had removed , piston , head camshaft and tryed with a hammer and a piece of wood to hit the crank and nothing happen..

Rudolph Hart

You need a puller to remove the tapered prop driver then the crank will fall out the back.Heat the crankcase with a paint stripper gun and tap it on a block of soft pine and the bearings will fall out too.There is some good info on the saito engine forum.

earlwb

You have to heat the engine up good first. Get it nice and hot, but not too hot. Then the crankcase expands more than the bearings do. Then you can press out the crankshaft. You can put the engine into the oven set for about 350 degrees F and let it heat up good. Then have at it. I would suggest wearing a good pair of gloves as it'll be pretty hot.

Ernie Misner

Anyone have a good link for him? He might need info on retiming the cam too. In the 2-cycle bearing link I have the guy uses a butane torch for heating the case.

Hobbsy

My Feedback: (102)

As mentioned, did you remove the prop driver? It comes off hard in most cases.

tigil

Ok tk's for your help :-)

1QwkSport2.5r

Using a torch to heat the case is risky business. It's pretty easy to warp the case due to uneven heating. I always recommend using the oven to heat the case as the temperature is more easily controlled and the heating is far more even. I start out at 325F and if the bearings don't come out I step it up 25F at a time for 5-10 additional minutes until they come out.

SrTelemaster150

^^^What he said^^^

It might be prudent to do this when Wifey isn't home.

1QwkSport2.5r

I changed bearings in an engine earlier this week; soaking and rinsing in clean methanol minimized the burning oil smell in the house. I did it while the wife was away at work and incidentally she didn't notice any funky smells in the house so my rinse trick worked I think.

Rv7garage

My Feedback: (10)

Obviously we would want to remove the carb before heating. Should the valve covers be removed as well?

blw

My Feedback: (3)

You get the carb off as you are taking off the backplate, so it's already done. You can just leave the valve covers on. No reason to take them off. The engine is then pretty much ready for heating up.

1QwkSport2.5r

Wouldn't you need to have the crank and cam out and thus the pushrods to change bearings? If that's the case, wouldn't you want the valve covers off to disassemble the valve train and to check valve lash when reassembling?