Reuse new head gasket and studs

[akart]

I am wanting to torque a new head on to measure push rod length. Can I torque the head,do my measurements,then take the head back off to change out the light checker spring,then put the same gasket back on. Engine will not be run.
I also have head studs installed,only about 1K on them. Can I reuse these head studs. Same engine just new heads.
Thank you.

[MikeB]

Depends on the gasket. Parts of some will stick to the head or block surface even at less than full torque. I'd install the heads permanently, and then change out the checking spring(s) with the head installed. I have a valve spring compressor tool like this, and it works great.

https://www.summitracing.com/parts/oes-25064?rrec=true


***Also, make sure to use high temp thread sealant on the studs, or coolant will trickle past the threads up onto your heads. And run a thread chaser on the block threads. Stud threads must be pristine and sealed well, since they are only slightly more than hand tight. Better yet, use head bolts instead of studs.

[rpmerf]

Studs are typically reusable. Bolts are typically torque to yield and should be replaced.

I would not risk reusing the headgasket.

Sounds like changing the springs with the head installed would be easiest. Load the cylinder up with air like you are doing a leakdown test.

[Dead Parrot]

I would think you could snug the bolts/nuts to 5 or 10 ft/lbs to take your measurements. There is more then enough adjustment in the rocker nuts to cover the few thousands of an inch between 10ft/lbs on the head fasteners and full installation torque.

For that matter, if you have an old set of head gaskets similar to your new ones, use the old ones for your measurement assembly and save the new ones for your final put together.

[Richard2112]

I did the same thing and bought a new set of gaskets. It's been said that as long as you don't heat cycle the head gasket that it's usable. I didn't want to take the chance. I know it sucks but it's better than the alternative.

[MikeB]

What kind of engine are we talking about? Torque-to-yield bolts (used in LS-type engines, for example) are torqued beyond the state of "elasticity" using a torque angle gauge, and become permanently stretched. That is not the case with head bolts used in conventional small blocks and big blocks.

I wouldn't say it's a must to replace the standard bolts, especially in a street engine, but new ones are relatively inexpensive. I've used the set below from GM several times, but I have also re-used bolts after thread-chasing them.
https://www.jegs.com/i/Chevrolet-Per...95499/10002/-1

Something that's almost never discussed is using standard length bolts with aftermarket heads. Make sure the bolt goes at least full 6 turns into the threaded hole, and preferably 7. Rule of thumb for cast iron is "Depth into threaded hole = width of fastener." So, a 7/16"-14 head bolt needs 6.125" turns. I once installed a pair of Dart Iron Eagle heads where the bottom 8 bolts would go only 4-5 turns into the block. Ended up stripping one hole and had to repair it with a Heli-coil. Eventually bought a set of slightly longer bolts.

[MikeB]

Originally Posted by rpmerf

Sounds like changing the springs with the head installed would be easiest. Load the cylinder up with air like you are doing a leakdown test.

Good catch! I forgot to mention that. And make sure the piston is in a position to stop the valve from falling into the cylinder. This shouldn't be an issue on a stock setup with an o-ring on the valve stem.

[TrailerTrash]

Originally Posted by MikeB

Good catch! I forgot to mention that. And make sure the piston is in a position to stop the valve from falling into the cylinder. This shouldn't be an issue on a stock setup with an o-ring on the valve stem.

You can jam a piece of rope in through the spark plug hole for some extra insurance. Then use a metal dental hook or pick to pull it out

[rpmerf]

I've done the string trick too. I didn't have the easiest time getting the string in. Started with the piston down, pushed a bunch of string in, then spun the engine around so the cylinder was TDC.