Head Gasket Swap Pics

[nienberg.11]

A few months ago I started to notice some steam at idle, and quickly came to the conclusion that my head gasket had failed. I was right. Since this is a well-covered topic, I'll let the pictures do most of the talking for me, but it should be noted that the head gasket was completely intact and had seemingly just rotted to the extent that water was getting past it.

Below I've marked the narrow area between cyl 6 and the water jacket where I believe the water was seeping through.

Here is the head before any cleaning.

2 hours of scraping and emory-papering later, here's the result. I did the same to the block, of course, but didn't take pictures of that.

[nienberg.11]

Did you put a straight-edge to that head? You're probably not going to like the idea of resurfacing the head since you're already pushing it running the na c.r. and the shave will raise it some. Maybe you could find a P90 and have it cut 0.020" or so (because you'll probably miss the off-boost response you had with the 8.3 s.c.r.). DAW

 

I didn't mention that since this has been discussed plenty of times, but it's a good point to bring up. Indeed I did put a straight edge to the head according to the method shown in the Chilton manual and it was within specs.

[slownrusty]

Up to 6-8thou is acceptable from a straight edge and a feeler gauge

 

Looks good from the pics....I will be going down this road very shortly.

 

Yasin

[nienberg.11]

I followed the tolerances listed in the repair manual. I don't recall the exact number off hand, but it was within the range you said.

Since the swap I've driven ~1000 mi. with the steam cleared up and no new issues.

[nienberg.11]

I used a beck-arnley (stock replacement) gasket with no sealer. Neither the manual or the gasket manufacterer recommended the use of a sealer. The bolts were in fine shape and I torqued them 3 lbs over specs to 65 ft/lbs since the car is now turbo'd.

[nienberg.11]

The n/a head bolts are some of the few truly high quality fasteners on the car from what I've experienced. I don't want to torque them beyond 65 ft/lbs, so I'll probably stay with them. If I ever see an old Z in an Ohio jy, I'll look for some spare bolts, but it's not likely to happen here in the rust belt. Out of curiousity though, what advantage does the groove in the top of the turbo bolts offer?

[pjo046]

I would think the grooves only makes them easier to distinguish from the NA bolts.

 

Yes, the NA bolts are some high quality fasteners, but the turbo bolts are better. But of course your best bet would be studs, as studs are far superior to bolts. ARP head studs are highly recommended.

[nienberg.11]

Guys, thanks for all the input. I totally agree with all of you that it would be better for me to have turbo bolts or studs, but you have to keep in mind that this is an n/a block and any detonation is going to shatter my ring lands or piston skirts long before my head bolts get dislodged from what I've heard.

 

If I could get my hands on some, I'd put them in the next time (hopefully there isn't a next time) that my head is off, but this is just a daily driven, slightly powerful car. As long as it gets me across town and doesn't leak or use any fluids, that's good enough. I'm not going to race it or set any new HP records.