Hey guys I have a few more questions for you. And you guessed it its about cylinder heads

1. How hard is it to remove them
2. Do you need to replace the bolts like the autoparts stores say
3. Any Major advantage for removing the the heads rather than just a compression test


Thats all i can think of now. Any help would be appericated

 

No need to remove them, unless you are planning on freshening/porting/polishing/etc them.

As far as teh bolts, I don't know - I reused mine, on a boosted motor, so....

 

Doward made what we in the biz call a "mistake" (poking fun at ya man). No, it's not a good idea to re-use the bolts, they stretch adn don't torque properly when re-installing. Anyhow, you do a compression test with the heads ON the motor. Only reason to take them of is the aformentioned port/polish/refresh, or if you're doing chamber work, or machine work to them. Hell, why not take them off and deburr the ports. Go ahead and gasket match them too, it's pretty easy, and it'll give ya some extra power (quite a bit I hear....but that's debatable until more people do baseline testing like myself...)

 

I'd like to know the composition of the stock bolts, and exactly how much 'stretching' is going on I cheaped out, I know

 

i have reused mine twice on this motor........

 

hmm are new head bolts expensive?

 

Yes the head bolts do stretch! If you re-use a head bolt, you can strip out the bolt hole in the engine block!! That happened to a guy on here, 82-T/A (the dude with the Fieros), and he had to get the block fixed.

Last I checked, a set of head bolts was $25; that's worth it, in my opinion.

But... at your own risk, if you do re-use a head bolt, you don't want that bolt to get "tight" as you spin it in. Remember everything's machined; you're not putting up a wooden fence with wood screws! You should be able to spin that bolt in all the way by HAND, and only use a torque wrench for the final tighten.

If you're spinning the bolt in by hand and it gets stuck HARD, then guess what, the head bolt stretched. If you force it in with a wrench, you'll strip the threads out of the block.

I still recommend buying new head bolts. See this message: https://www.thirdgen.org/techbb2/sho...threadid=60961

But... a compression test?? You don't remove the heads for that... you screw the tester into the spark plug hole- same with a leakdown test. Or do you mean measuring the combustion chamber?

As for how hard... well... taking them off is pretty easy. The hard part is getting everything else out of the way. Then you've gotta scrape the old gasket off while trying not to let it fall into the coolant holes or block any oil passageways OR scratching up the deck. (You can use a piece of brass pipe as a scraper, it won't damage the iron block) And all the while, you're leaning over the fender. Not my idea of fun!

 

how do you strip a bolt hole because of putting a used bolt in it? also, those bolts came out of those holes...why would screwing them in mess up the threads? IF you have bolts that won't torque down, they must be stretched and need to be replaced. IF they screw in fine and torque down fine, they are fine.

 

Not quite... The problem with stretched bolts, is that after a certain amount of 'stretch' they simply snap.

Reusing the stock bolts is a gamble, yes, but in my case, I needed to finish the upper end of the motor RIGHT THEN, and nobody had any in stock - so I wirewheeled 'em, and reused them, @ 70lbs/ft tq down. Retorqued @ 500miles.

 

The vast majority of the time it is perfectly acceptable to reuse head bolts. In theory it is a good idea to replace them in case they have stretched, but it is not common for bolts to stretch. Bolts typically stretch or break because they are overtorqued. Buy a good torque wrench and use it, following the recommended tightening sequence! Bolts that don't thread in smoothly typically have dirty threads or a dirty hole full of leftover thread sealant. Use a thread chaser or a tap to clean the hole out.
I reused the head bolts on my v8 diesel when I did the heads on it. They are torqued about twice as tight as our v6 engines, and no problems with 40,000 + miles so far.

 

These arent ford engines with torque to yeild bolts. Unless the old bolts are physically damaged, they can be reused. Ive only ever replace head bolts once. Every other time ive reused them, never had a blow gasket or leak.