Engine/Transmission (1994 - 1998) Coolant seeping during stud re-torque

[JGheen]

Has anyone had this happen before?

I was doing my typical line re-torque of the studs and when I got to the second row after the long/rocker studs, I was working my way forward and the third one from the front had started seeping coolant out of the bolt hole. This had never happened before and I am really hoping I didn't blow the HG already. Anyone have any thoughts on this... .

The only thing I did different this time was remove each nut and washer and re-apply some ARP lube as it had been quite some time since my last re-torque and I thought it would be a good idea after my 3 hard sled pulling runs in Vegas a couple weeks ago. No oil in the radiator nor coolant in the oil, but for coolant to come up through that hole and that hole only out of them all was a new one on me.



Thanks for the help, Joe

 

[BAnsley]

Does Arp recomend any type of sealer on the threads entering the block? Good luck, Brian

 

[JGheen]

Not from what I have heard. I just applied the ARP lube to both ends of the studs when I originally installed them and this had never happened in any of my past re-torques. This was probably my 9th or 10th re-torque that I can recall and the first in quite sometime. Again, I just thought it would be a good idea since I never took the engine above 3500rpm, over 50lbs of boost and EGTs over 1600*F. Vegas was the first time the engine has seen some serious load and heat to it not to mention pulling a sled.



Joe

 

[Hammer]

Joe...

Why so many retorques on the headstuds????.

Coolant leak could be anything from a simple passage due to excessive boost from lifting the head some during your pull and it setting back down without compromising the gasket to the beginnings of a cracked head. Only two ways to find out what it is,finish the torque job and run her till she shows whats wrong or tear her down because your not comfortable knowing of the possible problem. I would probably send a sample of oil out for a quick looky see to find out if they detect any coolant before I tore her down. It could be a easy solution to your dilemma..... Andy

 

[BPonci]

I have had the bottom of the head stud bore crack and repaired it with a little pipe dope on the threads. Ran it for a few years with no problems due to that issue.

 

[JGheen]

Well, not going to worry about it for now unless it becomes an issue. Just gonna pull that stud and put a bunch of thread sealer on it and run it. Hopefully it will hold with no issues, just not looking forward to another HG replacement if it comes to that. :{ Almost broke my back putting the head back on the last time during the 'ol driveway R&R.



Joe

 

[Bart]

I still want to know why so many re-torques? I have 170K on the clock and haven't touched mine. Tell me/us why, please

 

[K5IP]

Bart,

I just retorqued the head on my "mostly stock" 95. Most of the bolts only moved about 1/8 turn, but one, on the front of the engine measured only 85 ft. lb before I retorqued it. I got nearly a half turn on that one.

Guess it was time, 120K miles, even lfor a stock truck.

Rog

 

[JGheen]

I still want to know why so many re-torques? I have 170K on the clock and haven't touched mine. Tell me/us why, please

Cheap insurance to keep the o-ring'd head in check. Apparently I was told to give it about 5-6 re-torques in the first 20-25 heat cycles and then maybe once in a while after a good weekend of hard running with high EGTs and boost numbers such as my Vegas weekend of 3700rpm, 52lbs of boost and 1600*F+ of EGTs. Originally, it took me about 6 or 7 re-torques to finally get the scribe marks on the nut and stud to line back up. All the ones before, the nut tightened down about and 1/8" to 1/16" past the scribe marks each time till that 6th or 7th re-torque. It just kept sucking that o-ring in the head into the headgasket. So far everything has been fine and it's no biggie to me, again just cheap insurance. I definatley don't look forward to replacing the HG anytime soon, not a fun/easy job one bit.



Joe