Complete Misfire on Three Cylinders

[Captain Obvious]

So today's question... Back to the head gasket.

The original head gasket for my 77  listed on the parts fishe is 11044-N4200. I believe I have traced the superseding history as shown below:

11044-N4200 - 09/1974 - 04/1980
11044-N4210 - 05/1980 - 02/1981
11044-N4220 - 05/1980 - 02/1981  (don't know why there are two of them. Might be turbo)
11044-N4221 - Supersedes all of the above

Then when they went to the F54 block, they changed the head gasket:

11044-P7900 - 80-82 GL (turbo)
11044-P7910 - 81-83 GL and non GL (everything 83 turbo and non turbo)
11044-P7911 - Supersedes all of the above

And I believe the latest part number for the F54 gasket is 11044-P9600

So the question is... Can I used the same head gasket that was intended for the F54 block on my N42 block instead?

[Zed Head]

The head gasket/block/head combinations discussion can get convoluted.  Especially if you get in to what the high power guys do to their heads to balance the cooling, drilling holes and attaching extra coolant lines.

Sometimes people assume that all of the passages available need to be open and flowing as much as possible but if you follow the Nissan design path it looks like they modified the head gasket to control flow, by blocking or reducing the size of certain passages.  There was a picture recently that showed it clearly with rust spots on the head gasket where the ports were blocked.

So if you're mixing head and block you have some thinking to do.  I've always thought that the head gasket should match the head.   The head is what warps if cooling is bad, the block is essentially just a reservoir of coolant.  And it's not a block gasket, it's a head gasket.

[siteunseen]

That's the reason I don't like felpro HGs.  They go from '70 to '80, same part number.  Something changed in 1981 Captain Obvious.

[jonathanrussell]

I have new in box nissan original, as follows.

11044-n4210

11044-n4221

I also have an original used 280z gasket pulled from my engine and saved. 

The two new gaskets noted above are identical in terms of cutouts...as is my used gasket. The n4210 gasket and the n4221 gasket differ in terms of the materials used. The newer gasket has more of a foil like surface. My original used gasket is more like the n4221 gasket material...more rigid....more like the beck arnley gasket I mention below but with some sort of stuff sprayed on it (if I were guessing I would say something like copper coat). 

I have a stash of 280z aftermarket gaskets too. One is from a stone / ishina headset kit. The part number is A1042-P692K....plus another number....JHS-00168-N. The head gasket in this kit looks very similar to the n4221 nissan gasket. Cutouts are identical. Materials are very similar...more of a foil like feel. There are minor differences though. Ishina gasket has copper around oil passages where nissan is aluminum or steel. Nissan has some sort of sealant running around the timing cover area.

Fyi, i also have a felpro and the cuttouts in terms of water passages are the same.

Beck Arnley...cutouts are the same but material is entirely different....more like two pieces of rigid card stock pressed around a foil center.

I should also mention that i have a stone/ishina that is not part of a headset kit....single gasket. The material used for this gasket is more like the Beck Arnley.

I used felpro in my last build. So far so good but time will tell. One thing i have observed is that the felpro is thinner. Not a big deal unless you are concerned about even a bit more compression...detonation.

Finally, I should mention that my stash of aftermarket gaskets is 5 years old (except felpro) so much could have changed if you order today.

For you, I would probably suggest a nissan11044-n4221.

 

Edited July 25, 2019 by jonathanrussell
spelling

[Patcon]

Courtesy Nissan shows out of stock, ships in 2-4 business days

$44.43

[Captain Obvious]

Thanks for the input guys. I haven't figured out what I'm going to do with a head gasket yet, but I'm looking into it. I've got two of the later ZX gaskets on order and I may end up using one of those, but haven't finished the investigation yet.

Todays question.... Would I be completely shunned from the collective if I re-used head bolts? I've got three sets of used bolts here and I'm sure I can put together one set that looks great from the three sets that I have. What say ye?

I'm planning to cut the heads off a couple of the old rusty long ones to use as guide pins to get the head lined up easier during the re-install procedure, but even with that, I've got enough remaining to make a good looking set.

[S30Driver]

I vote to re-use your best bolts.  I assume you are on a budget for this rebuild and although nice to have the new bolts, especially the turbo version, I think you will be fine after you chase the block threads.  You don't want to unnecessarily cut into the mico brew summer budget.   Mike however may deduct 10 reputation points from you per used bolt.

[jonathanrussell]

I assume you have the dowel / guides that help you align the head to the block. Your comment about using a cut bolt makes me wonder if yours are missing due to PO.

 

I would use ARP studs with nuts. I don't like torquing into the block threads. 60 ft pounds of torque too (though I think the turbo bolts are same). Just me. ARP not cheap though so I get it.

 

[Patcon]

I'm with Jonathon. I like the ARP studs but I have reused bolts in the past and have never broken one. I believe, possibly in error, that if they survive the torquing down then they should be good to go.

[grannyknot]

Re-use

[Captain Obvious]

OK, so here's the plan then... I'm hoping that I'm doing such a thorough job with the head that it'll never ever ever have to be pulled off that block again. The threads in the block should be able to hold one more torqueing!

I've sorted through my head bolts. Four of the originals were rusty and didn't make the cut. I've substituted four others from the spares group into the batch that I will re-use.

Thanks for the input guys.

[Captain Obvious]

11 hours ago, jonathanrussell said:

I assume you have the dowel / guides that help you align the head to the block. Your comment about using a cut bolt makes me wonder if yours are missing due to PO.

I'm waiting for new ones to arrive. I ordered new dowels for the head to the block, and also a complete set for all the cam towers. Under closer scrutiny, my cam tower alignment dowels were pretty badly abused. Even the ones that I thought were OK (because they fit into the holes) only fit because my PO had already filed off the pliers he used to man-handle them out of position. Forget it.... I ordered all ten. And I figured that since I was already paying for shipping, I got two new dowels for the block.

The status of the head at this point is all the valves are in. All the seats are clean and the valves all seal. All the springs are oriented the correct way. Didn't forget any of the hardened washers. Didn't forget any of the valve stem seals. The valve cover holes that I plugged with the aluminum inserts have been drilled and tapped.

The head is sitting on the bench in a holding pattern now waiting for the tower dowels to arrive. Once they get here, I can put the towers on and get the cam installed.

About the only new item of interest is that I found burrs kicked up on the inside corners of a couple of the valve retainer wedges. The tips of the burrs were shiny with the implication being that the burrs were contacting the valve stem at the bottom of the locking groove that the retainers lock into. So... Basically, some of the valve retainers were not seating in that groove completely because the burrs were in the way. The burrs look like they were caused when the retainers were forcibly pushed into place when the valve spring really wasn't compressed enough. Hit the retainer on the hilt with a hammer and screwdriver and it'll snap into the groove. But it may take a corner out on the way!

With my valve contraption, I was able to compress the spring to the point where the retainers fell into place. No forcing required.

I look back at some unexplained weird engine behavior over the past couple years and I think it's all coming together. Things like...

I set the valves. Then check them again in a couple hundred miles and they're off far enough that I readjust. Then check again in a couple hundred more and they're off the other way. I think stuff like the cam towers not being seated properly and burrs on the retainer wedges are the reason for the instability. And since some of the head bolts go through the cam towers, it couldn't have been doing good things for my head bolt clamping pressure either. Which probably explains my slow minor coolant loss. I think it's all related.