z22 that is bored .040 over........gasket problems

[Lz22]

I have a z22 bored .040 over and have burned through stock gaskets and am just now figuring out its not working. 

 

Can an anyone tell me where to get oversized head gaskets? Or point me to other people or forums that might know. 

Thanks

[datzenmike]

Check the head is flat with a straight edge. If you can slip a 0.004" feeler gauge under it it needs milling flat. 0.004" is about the thickness of newspaper.

 

Here's mine it's about a meter long.

 

 

0.040" is one mm so the cylinder is only 0.020" larger all the way round or 5 thicknesses of newspaper... not much. A stock gasket is still large enough to work with this. You can try ordering a Z24 gasket. The Z22 bore is 87mm and the Z24 is 89mm. Most likely if you order one you will get a 'one size fits all' gasket for the Z20, Z22 and Z24.

 

Be sure threaded bolt holes in block are clean. Bolts in good shape and threads lightly oiled.

 

Torque to 20 ft lbs in this sequence...

 

R  A  D

8.......7

4......3

2.......1

6......5

10....9

 

Now torque to 40 ft lbs, same sequence.

 

Finish torque to 60 ft lbs same sequence.

 

Just to be safe, in a months time after several dozen heat cycles, but when the engine cold from sitting over night, loosen ONE bolt and tighten to 60 ft. lbs. Loosen the next bolt and tighten to 60 ft. lbs. Do in any order you like as long as only one bolt at a time is loosened.

[Stoffregen Motorsports]

A stock gasket will work with an .040" overbore.

 

Do you have an L head on it? If so, you need to punch an extra coolant hole in the back of the gasket.

[Lz22]

I do have a L head on it. Could you tell me where at on the gasket?

 

[banzai510(hainz)]

Stroffergren

would this work?

https://www.ebay.com/itm/234726476815?_trkparms=ni_actn%3Anav|ni_nt%3AWATCH_ITEM_ENDING_SOON|ni_apos%3A1|ni_sg%3A1|ni_pos%3A1|ni_st%3ANEW|ni_wh%3A1|ni_nid%3A723601505344|ni_nsid%3A234726476815|ni_bn%3A1&_trksid=p2380424.m570.l5997

[datzenmike]

 

I found the Z series head gasket does fit the L head but is close at one spot. This was solved with a little JB weld. Naturally the two 10mm bolts won't fit so a very small smear of RTV is advised.

 

 

Z24 block (assume the Z22 is the same) front right just to rear of timing cover. There is a head bolt hole and that's all.

 

 

Above, L head gasket on top of Z24 block shows the two missing holes and how close the middle one is to the outer edge.

 

 

This is the L head above it. Note the head bolt hole to the left but there are two additional holes for coolant. The middle one is perilously close to the outer edge of the block below it.

 

 

Again JB weld for the win to give more surface for the Z series gasket to seal. I also Dremeled a groove between these to holes to join them rather than drill an additional hole in the block.

[Stoffregen Motorsports]

1 hour ago, banzai510(hainz) said:

Stroffergren

would this work?

https://www.ebay.com/itm/234726476815?_trkparms=ni_actn%3Anav|ni_nt%3AWATCH_ITEM_ENDING_SOON|ni_apos%3A1|ni_sg%3A1|ni_pos%3A1|ni_st%3ANEW|ni_wh%3A1|ni_nid%3A723601505344|ni_nsid%3A234726476815|ni_bn%3A1&_trksid=p2380424.m570.l5997

Yeah, that should work.

 

On the stock gasket, there is a triangular hole in the back of the gasket that matches a triangular passage in the back of the block. I have seen Z series gaskets that did not have this hole punched out. A gasket punch, or leather punch, or even a utility knife can be used to cut the hole.