scmedic

I was adjusting the valves on my 87 4runner / 22re over the weekend and decided to check the cylinder head bolt torques while the cover was off.

Everything checked out fine with the exception of the exhaust side bolt between cylinders 3 and 4 which spun freely :-(

The bolt and the bolt threads are intact with no apparent damage so I assume the threads in the block are stripped.

The truck is relatively new to me (less than 6 months). It;s got 158k on the clock but I don't know what the maintenance history is. It is running fine with no overheating, no oil/coolant mixing.

I know the definitive fix is to pull the head and helicoil the block but I'm short on time and money right now and am wondering if anyone has a suggestion on a temporary patch? I was thinking if I replace the bolt with a longer stud maybe I can get far enough past the damaged threads in the block to allow me to torque it down?

Barring any fix, any thoughts on how long the head gasket seal will hold with 9/10 bolts?

maxpower_hd

I would try running a tap down the hole to clean up the threads first. Then you could try the slightly longer bolt. I know others have mentioned that they did the same thing and it worked. I would also recommend getting some assembly lube and coating the tap with it. It is fairly thick oil and the metal shavings stick to it quite well.

I personally do not like the helicoils. They have other thread repair solutions that are better, in my opinion. I have used the E-Z Lock thread inserts on other machinery applications with great success after having the helicoils break several times in the same application. They make different ones for specific uses, including head bolt repairs. I haven't used them on a head yet but they would be my first choice if it goes that far. You have to have enough meat in the metal to drill the hole but they will typically work anywhere a helicoil will.

Here is a link to their site.

http://www.ezlok.com/

Good luck.

MMA_Alex

i would try chasing the threads and cleaning em up with a tap. If you cant afford pulling the head right now, and that dosent work you could try to run it as it is. Assuming you dont get it real hot it should probably hold for the time being, but i would get it fixed soon so you dont end up stranded some time in the future.

scmedic

Thanks for the advice!

Any suggestions on where to find an extended length head bolt or stud? The only ones I have been able to find are the ARP studs and the stock head bolts.

Also, I've got the right tap to chase the threads from previous head gasket jobs but it's too short to reach the block through the cylinder head; are extended length taps available for jobs like this?

Thanks again,
Mark