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Old 12-01-2008, 05:39 PM   #16
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Originally Posted by butch man View Post
When ever you replace bearings make sure to insert the crank to align the new bearings before the block cools. If you cant get the crank through easily dont force it one of the bearings are cocked. If the block cools like that & you force the crank through & call it good you may very well crack the block. You can gently tap the bearings in to seat them with the correct size socket if you like but gently tap is not the same as beat in. There should be no "FORCE" required for install or something is not right.
Just thought i'd add a little hint for installing bearings.

To get the bearings in straight, the best way i've found is to heat the case in the oven to 400F and while heating, install the main bearing onto the shaft and put it in the freezer in a plastic bag along with the front bearing so that the whole assembly will be nice and cold.

Remove the case from the oven, install the front bearing so it sits flush with the front of the case. Then hold the case while hot (use an oven mit) with the rear pointing up and then drop the shaft and bearing into the case. It should all fit nice and snug and the bearings will be straight. If the shaft doesn't fall all the way in, you can tap it home with a plastic screwdriver handle.

Hope this helps
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Old 12-01-2008, 05:39 PM   #17
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why not spend forty more dollars and put two ceramic bearings in the motor
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Old 12-01-2008, 05:48 PM   #18
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FYI... the piston/sleeve fit will loosen up when the engine comes up to temp. All of the heat is at the top end of the sleeve, this is why the sleeves are milled with a slight taper, so they are tight at TDC. Once the sleeve heats it will expand and the piston will move freely.

I, on the other hand, do not subscribe to "Pinching" sleeves. I ring the piston.

chunk
How exactly do you do that? Pipe cutter? Heard that one, but never tried it. Did you have a bad "pinch" experiance?

Here's another vote for Rayaracing.com can't go wrong with him and an absolute great guy to work with!!
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Old 12-01-2008, 07:29 PM   #19
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How exactly do you do that? Pipe cutter? Heard that one, but never tried it. Did you have a bad "pinch" experiance?
PIPE CUTTER!!!!! Man, you know how to hurt a guy.

To Ring a piston you need to chuck the piston in a lathe and use a sharp carbide cutter. Cut the groove about .060" down from the piston face and .003 to .004" deep (I like to do a second cut .008-.010 below the first cut). When you are done - with the piston face up - the cut would look like an upsidedown "7". The 90-degree corner that the cut forms with the cylinder wall will pack the oil into the ring on the up-stroke and the bevel will force the oil out against the sleeve on the down stroke giving an air-tight seal. If you get any chatter during cutting, the sleeve is toast. I let an experienced machinist do the work for me.

Can't say I've had a bad experience with pinching...

chunk
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Old 12-01-2008, 07:31 PM   #20
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+3 for Rays Racing for Pinching.

I had Ray do one of my V-Specs after 12 gallons, and it went anther 8 before it just wouldn't idle consistent and started to ghost flame. Well worth the cost to have it pinched.
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Old 12-01-2008, 07:39 PM   #21
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Why oh Why would you put a stock bearing back in? I assume thats how you got such a rediculous price for the rear bearing? Try this on for size.

http://tkocompetitiondev.com/shop/

should be between $30-40 for 2 ceramic bearings. These are the ones 80% of us use.
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Old 12-01-2008, 08:23 PM   #22
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Originally Posted by chunk t View Post
PIPE CUTTER!!!!! Man, you know how to hurt a guy.

To Ring a piston you need to chuck the piston in a lathe and use a sharp carbide cutter. Cut the groove about .060" down from the piston face and .003 to .004" deep (I like to do a second cut .008-.010 below the first cut). When you are done - with the piston face up - the cut would look like an upsidedown "7". The 90-degree corner that the cut forms with the cylinder wall will pack the oil into the ring on the up-stroke and the bevel will force the oil out against the sleeve on the down stroke giving an air-tight seal. If you get any chatter during cutting, the sleeve is toast. I let an experienced machinist do the work for me.

Can't say I've had a bad experience with pinching...

chunk
Is the rolleyes b/c I spelled experience wrong?
That's the first time I've ever heard of your method. I have a lathe so I may give that a try next summer with a boned engine. Sounds interesting. But I am not sure how the compression would not blow the oil out of the groove and break the seal? But sounds neat enough to try. Thanks for the idea.
: )
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