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Little Trucks, Big World

Hi 720 fans,  blew the head gasket on my Z24 (on surprise there :-(  engine overheated.)  And took it apart and checked the block and head.  Block within specs but the head is toast.  Will get a rebuilt head.  My question is what is the best brand of head gasket to buy?  Lots of brands and want to get the best.  Thanks for your help.  Also can the head bolts be reused, having trouble finding new?

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Define toast...

Usually overheating will only warp the head. This can be fixed by having it planed for $30 -$50 and need not be replaced.

Felpro h/g are ok, just about any will work. The secret is getting the head flat, clean the bolt hole threads, clean the bolt threads, block and head surface must be clean enough to eat off of and most important is the tightening sequence.






9..10 Use this sequence and tighten to 20 ft. lbs. Repeat the sequence and torque to 40 ft lbs. Finaly repeatthe sequence and final torque to 60 ft lbs... done.

Next weekend after a half dozen full warm ups and cool downs and when the engine is dead cold, re-torque the head bolts. Loosen only one at a time! and immediately torque to 60 ft lbs. You can do this in any order you like BUT only one bolt at a time lose.

Re-torque the head bolts every tune up or about once a year.

I assume you blocked the timing chain so that the chain tensioner cannot fall out???

Thanks for the info.  I got a rebuilt head because the old one may have 180k miles on it.  I used a wire brush on the block to clean and will clean with engine cleaner before new head is installed.  As for the timing chain, I learned about that about 4o+ years ago the hard way...LOL.

Have the head milled flat, make sure everything is clean and do as Datzenmike says.

I prefer to use Victor Reinz or OEM Nissan on the head gasket. The metal firing ring is weaker on the FelPro, but ironically that is the only FelPro I had a problem with. If I had an example of one, I would show pictures.

But toast on the head? Doubt it. It takes a lot to kill that head.

Thanks, I will get the head rebuilt as it may have 180k plus miles on it and have a spare on hand. 

Will rebuilding the head fix the problem,are your spark plugs oily,if so then the piston rings are bad,on my stock engine,had the head gasket blow a few times,switched to a better mechanic,the other one said he sent out to get machined,we'll that was a big lie,the other mechanic took head off and said it was straight and was still at factory settings,then he checked it more and was decided the piston rings were bad,my exhaust plugs were getting oily faster than I could drive to work,12 minutes,went and got a remanufactured engine,plus the inside of the intake manifold had a crack in it and it was welded and fixed,our z-24's has alot of hidden problems,but if the head gasket goes then something is causing it,must find the problem before doing a head gasket job,this is just my experience I had years ago.

The head gasket went because the engine over heated due to a broken hose.  The plugs all look great, all a nice light brown.  Was running super before hose went.


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