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Building a KZ Head - calling all engine experts to the scene

Beau

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Jan 28, 2011
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guyana
I'm finally putting together the AMC head I've had stored for a good few years now, but upon assembling it all have run into one main issue.

I'll walk you through what I've done. I have a new head, new valves, springs ect.

I seated the new valves into the head using a hand lapping tool and some valve grinding compound paste. All went well. I then assembled all valves into the head.

New lifter cups installed. Now the SHIMS- This is where the trouble came up.

I didn't purchase new shims because of course they need to measured and the correct ones ordered. So I put some used shims in and read the clearances, of which all were out.

However, upon using Toyota's graph and selecting the appropriate shim size, it seems even the biggest shim won't bring 3 out of the 8 valves in spec. They will be out by 0.10-0.15mm. One would be 0.20mm out.

I'm running the options in my head and the only way to solve this issue is to grind down/lap the valve seats more so that the valve can seat slightly higher, thus reducing the valve clearance gap, does this make sense?

Otherwise how else do you guys suppose I get these valves in spec? How do the pros go about it? Valves are correct lengths as well. I'm puzzled
 
Also does anyone know where's best to source the shims? I normally use Amayama which have them, and at good prices too, but it's usually a good couple weeks at least till they arrive.
 
I am sorry I can't help Beau but will watch this thread closely.
Good luck!
 
As long as the valve seats are fully seated in the head then grinding in is the way to go. An engine workshop that does head work will have a valve seat cutting machine which will be better to take a clean cut around the whole face of the seat than using a lot of grinding paste and elbow grease. Then it’s just a case of lapping in the valves a tiny bit so they are mated.
 
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I figured this may be the only way. I'm gonna attempt to do the hard work of trying to seat them a little bit more first and if that doesn't work I guess I'll have to look into machining shops.

Lesson learnt I suppose, I probably should have bought an assembled head... But where's the fun in that?
 
Just thought I'd update this for anyone in the future.

Research showed that the valves should be seated into the head 0.010mm for 1KZTE heads and 0.040mm for 1KZT. With my new valves they were actually protruding about 0.030mm for the exhaust valves and the intake valves sat flush. Most of this height difference comes from the exhaust valve seat being slightly lower on the new valves vs the old. I gave in and used the old exhaust valves which seated flush with the head and hoped for the best. I used the 5 hole gasket which is 0.010mm thicker than the hole 2 that came out which I was hoping would provide the additional clearance I didn't have on the exhaust valves.

I measured up and ordered pretty much the thickest shim size toyota had which put me on the top end of the spec for the valves, but I have a slight feeling after running the engine it'll close up a bit.

End results were the engine ran fine, very smooth and no ticking on the top end which was a surprise as I had the clearances on the slacker end prior to install. Successful head swap in the end.
 
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