Kawi2strokes.com Forum

I believe that I know the answer to this question, but I wanted to check with the experts.

I've rebuilt several Yamaha two-strokes so I've been inside the cases a few times. This rebuild is my first Kawasaki. I assembled and torqued my KH500 engine with new seals and rebuilt crank, but had to take it apart since I did not get the kicker wishbone into the slot in the housing (d'oh). I noticed that the red locktite I put on the crank bearings had a thickness - one or two thousandths, indicating a small clearance between the crank bearings and the cases.

Is this normal? I would imagine that there should be zero clearance here. I have a spare set of cases that I can check to see if they have a tighter fit. What should I be looking for?

Thanks!

That's not normal. Is it possible the Loctite was hardening before you got it all together and tight? That can be a problem.

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If it surges, that's normal, upshift.

Hmmm. I put the locktite on the bearings just before I mated the case halves, so there was not any time at all before I torqued the crank bolts up.

From the Locktite site: The product cures when confined in the absence of air between close fitting metal surfaces.

I think I need to crack the cases again, clean everything up, and use some plastigage to check the clearance between the bearings and case. If it shows any clearance at all, I'll try my spare cases to see if there is a difference.

The problem happens when you put the halves together and start putting nuts on the studs. It takes a couple minutes to do that and start tightening them, so if the Loctite is not a slow hardening type it can start to harden before you want it to. But checking the clearances never hurts, especially if you think the two halves you're working with may not have been together originally.

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If it surges, that's normal, upshift.

I can't seem to find a slow curing red locktite. Could you give me a lead?

I know that the engine had some issues (like blowing up the center cylinder), so it may be that the cases were damaged. I'll disassemble and check.

Thanks!

Loctite 620 is what's recommended for this, and only in the tiniest of amounts. It's one of the many green Loctites.

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If it surges, that's normal, upshift.

Thanks!

examples..not!

Excel files not allowed?

cliff

excel files not allowed?

so a screenshot on one matching numbers case pair

So there is a slight negative clearance (kind of like a press fit). That makes perfect sense.

I pulled the engine today. Once I get back into the garage I'll split the cases and check the clearances with plastigage.

It is hot in Houston. Garage time in the afternoon is impossible. Even in the morning it's not pleasant. But I will persevere.