Help! rebuild questions

[alfie]

Hello revlimited i am in need of some help. i cannot find a complete rebuild kit for my m20. what do you guys that have rebuilt your motors done to aquire parts?

Also would i be better off just trying to get a local shop to rebuild it for me ? i am located in miami.

[alfie]

thanks guys !

[jlevie]

I've rebuilt a few M20 engines and I don't see how one could have a "rebuild kit". If you do the job correctly you will pick the "color" of bearings that provide the correct bearing clearance. Which means measuring all of the crank journals (after polishing) to a ten thousandth. Most of the time all of the main & rod journals will use one bearing size, but sometimes you have to use bearing out of more than one size set.

You also have to measure the cylinder bores to check for wear. If the cylinders are within limits you can have them cross hatch honed and use new rings. The end gap on the rings must be checked and may require adjustment. Depending on the degree of wear on the wrist pin bearing, the rods may need to be replaced (or rebuilt).

The head will almost certainly need to have the valves ground and new seals. Depending on the degree of wear it may need new guides, new rockers, or a new cam. This is job you have a shop do. In my experience a used head almost always has enough warp to justify surfacing. And frequently it will need new exhaust valves.

Do not have the block hot tanked. That will destroy the intermediate shaft bearings and they are a pain to replace. Of course, if those bearings are worn they will require replacement.

If you rebuild an engine, use a new oil pump and pressure relief valve.

If the cylinders are worn to the point that a rebore is needed, it will be cheaper to find a used engine.

[andrewm]

Well said, the only thing I would add to it...always always always get new freeze plugs.

[alfie]

Thank you guys very much. You were very helpful.

[TobyB]

well, and things like the rod bolts are 1- use only items...

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