Can the head and intake bolts be re-use?

 

but check threads and clean em up before install...run a tap through all bolt holes, run a die down all bolts, and use Permatex on everything!

 

 

I would be careful using a tap on the bolt holes. It can cut away some of the material and make the bolt holes more prone to stripping, espcially the holes in the aluminum heads.

You can take a bolt and grind the sides off the threads to make a home mead thread chaser, or you can buy the actual tool from a tool truck/store.

I would be hesitant to re-use the head bolts, but I would be lieing if I said I'd never done it. I wouldn't hesitate on the intake bolts.

 

You can reuse the intake bolts and I would only reuse the head bolts if they were in really good shape. Either way clean'em up real good.

 

I thought I could re-use my head bolts, all went well until the very last one. Just as I was putting the final torque setting the darn thing broke off. Even though all the others were already tightened to specs I was leery of them so I pulled them all and replaced them with ARP's which can be re-used. The intake bolts are perfectly okay to re-use.

 

I've reused head bolts with no problems. Just inspect them and clean them up with a wire wheel. It is very hard to break off head bolts on aluminum heads.....you just will crush the head in the area surrounding the bolt area if you over torque them. Intake to head bolts are very inexpensive...reuse or replace.

 

why would you run a tap down the holes in the head?

 

Intake bolts can be reused. Use the correct Torx bit and they should last. I would replace the head bolts due to their stretch. If one is weak and breaks in the block it could be a bear to remove. Think of how many heat cycles those head bolts have endured. GM probably used the cheapest vendor for these and that would constitute cheap materials. Spend the $ 20 for a Summit head bolt set for some insurance. +++ on the permetex.

 

I did not reuse the stock head bolts, I did reuse the stock intake bolts.

 

Second the caution on using a tap to clean bolt holes. A tap will remove metal. A set of thread chasers is a small cost to insure decent threads. Ditto for a die on a bolt.

Why clean correct threars? To insure proper torque and clamping. I wouldn't use stock head bolts but once.

 

LTx head bolts are "torque to yield" and shouldn't be reused. Having made that statement I have reused them. But, I've also read on other forums where a few have broke the head off bolts after trying to reuse.

 

Spend the $60 and buy a nice set of ARP head bolts. It's well spent insurance money IMO.

 

You are correct, just those bolts were brand new and only have 1,000 miles. They were torqued to 65 ft lbs

Oh well, I buy a new set to have peace of mind. Taping sealant off thread is a pain in the azz

 

If you have a grinder on your workbench, buy a wire wheel for it. Then it'll take less than a minute per bolt

 

The second post said to run a tap through all bolt holes. Since the intake manifold bolts to the heads, those bolts would be included in the term "all". The original poster was asking about head bolts and intake bolts. While this thread has taken the direction of being head bolt focused, I worded my reply in a such a way as to address both the head to block, and intake to head bolts.

Running a tap into the intake to head bolt holes isn't necessary, IMO. Cleaning them with some kind of thread chaser is a good idea. If you do use a tap, it can/will remove material. On the intake to head bolts bolts, the factory spec is somewhere in the neighborhood of 25 Ft. Lbs. That amount doesn't sound like much, but in the moment it sure feels to me like I'm on the verge of pulling the threads out of the head when ever I torque an intake down. Although I've never actually damaged/ruined the threads in such a situation, I can only accept the idea that removing material via tap would increase the likelihood of damaging/stripping out a bolt hole.

Aluminum is softer than steel. That is why I specifically commented on the threads in an aluminum head being the most prone to damage from tapping. In my opinion, for whatever that's worth, the factory torque spec is on the verge of damaging the threads. Removing material from those threads is something I would recommend against.

Your results may vary.

 

The guy who put my engine back together tried to re-use the head bolts, but didn't like the way they felt, so I went with ARP (which can be re-used).

 

Also, the ARP bolts are torqued normally, not torque to yield like the originals were.