Torque setting for valve cover stud?

jet911 · 06:57 PM

Last night I pulled the valve covers to do my first valve adjustment today and three valve cover studs came out vs. the nut coming off. I was able to get the nut off as described in another thread. Now I'm going to re-install using the double nut technique. I was going to put some blue loc-tight on the part going into the head. What should the torque be?

TIA

911pcars · 09-16-2005, 04:00 PM

If you use Lock-tite, just snug will do. The LT will hold the stud in place. Be sure to remove oil from the threads.

Sherwood

jet911 · 07:09 PM

Thanks Sherwood!

Pete Zimmerman posted to another thread over on Rennlist regarding the same issue and said not to use lock-tite. I followed his instructions. I cleaned the threads on the entire stud, screwed them back in after I completed the valve adjustment and everything worked out great.

Man did I have a tough time with the #5 intake valve. For what ever reason, I could not get the blade in the gap. I backed off the adjustment screw a couple of turns and still had a hard time getting the blade in. Go figure.... It took me nearly an hour just on that one valve, even the dreaded #6 was much easier.

Job was not as bad as I thought. For first timers, I highly recommend doing #4 first, go 240 degrees, do #5 go 240 degrees and do #6. Then go to the drivers side. When I got the "feel," it went pretty quick. Total time on the valves just under 3 hours.

jluetjen · jluetjen's Garage

You don't even need to go to Rennlist! There have been numerous posts here on Pelican on the subject of torquing the stud and nuts. Basically, the nuts are torqued to a very low level (lb-ins), basically slightly more then finger tight.

jet911 · 09-17-2005, 07:13 AM

John, thanks for the heads up, however I was not looking for the torque setting on "nuts," I knew that. In fact I purchased the silicone gasket set from our host and it comes with suggested torque settings, i.e., 35 - 45 inch pounds.
What I was looking for was the torque settings for the studs of which three backed out when I removed the valve covers as I noted in the original post above.

I did a search here and found nothing, hence went to Rennlist and found my answer.

BTW, those silicone gaskets are great. I had one small drip on the drivers side, now no drips!

Thanks again John!

Early_S_Man · 09-17-2005, 07:58 AM

Red high-temperature Loctite is what you want to use on those studs ... they aren't supposed to come out with the nut at an oil change, and the red is what is used on the cylinder head studs. It can be softened with heat any time you want to remove them, just as with head studs.

jet911 · 09-17-2005, 12:19 PM

Thanks Warren.

I followed Zimmerman's advice and didn't use any loctite. When I do the next valve adjustment, I believe I will order about a half dozen studs ahead of time just to keep on hand. I have a feeling that when I remove the nuts during the next VA, those same three will come back out again. In fact, I noticed there was a bit of scaring on one of the studs that lead me to believe it must have backed out and was re-inserted when I had a wrench to the last valve adjustment.

Zeke · 09-17-2005, 12:36 PM

If the threads are damaged, the use of Loctite is necessary. Follow Warren's advice. And Sherwood's, rinse out the threaded hole with brake cleaner and clean the stud as well. Oil and loctite don't mix well.

In theory, any stud only needs to be tighter than the nut torque specified for the nut used on that stud. However, expansion, contraction and vibration can play a part in loosening anything. For future reference, you can use the torque off the common charts for a bolt that is of the same size and type into the same metal to establish a torque range that will keep the stud in place. In some cases, you will find that the torque values are nearly equal if not downright equal between stud and nut. In this case, the use of Loctite is the factor that keeps the stud from turning first when you remove the nut. I'm not positive about any of this (especially here!), but the various pieces of the transmission case would be a good example. Ultra-thin gaskets that compress little. As with any gasket, you should recheck after 24 hrs and after some heat cycles. there are some exceptions like the VCs. Again, if the threads are damaged, all bets are off.

randywebb · 09-17-2005, 01:40 PM

There is a new BLue Loctite that works on 'unclean' fasteners - how oily -- who knows? But do the above even if you do use it.

I'm not sure that Blue isn't enough on this small of a fastener...

jet911 · 09-17-2005, 06:04 PM

Thanks gents. I love this board! The treads were not damaged at all. I could screw the studs back in nearly all the way using only my fingers. I think I'm okay. I will check the VCs next week and periodically to make sure the three studs don't loosen up.
I'm printing off this thread to put in my file of tech advice for future reference.

Thanks again!