1972 LT1 Aluminum valve cover bolt torque?

[Gary S.]

Maybe I am perpetually tired/slow but my searching here, the AIM, and Corvette Service Guide turns up lots of torque values except for valve cover bolts. Googling turns up numbers from various forums and technical sites of 2-4 foot pounds or 24-48 in-lbs. My memory has 36 in-lbs but I can't find it.

Btw, based on a recently posted question concerning oil leakage, I bought Fel-pro 1604 valve cover gaskets (thank you Joe L.) and yes they are thicker but if they stop leaks I'm ok. When torquing to 36 in-lbs, does gasket compression result in a fair amount of torquing beyond "that feels about right". I ask because, once I tightened them by hand, I put my inch-pound torque gauge on it, set to 36 in-lb, and turned until I was doubting myself until it finally clicked. I assumed that the cork-composite gasket was compressing. Wrong assumption or correct?

thank you as always.

[Mark E.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

I've always used the "that feels about right" method, and probably err on the light side. If they leak after a heat cycle, I then tighten a bit more. Check periodically and repeat as needed.

[Gary S.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

Mark,
I have always done the same with valve covers. However, I am trying to turn over a new leaf and rid myself of bad habits as well as curtail some leaks. the leaky cork valve cover gaskets were most likely my leak source but I will soon find out. My googling has revealed that many folks do it your way.

Right now I am re-doing brakes now that the valve covers are back on (torqued to 36 in-lbs) and I may dig into the steering to fix my always on door buzzer whenever the door is opened. I fixed it perhaps 10 years ago so it is easy enough to do. So, it won't be a while before I get the engine running.

[Joe L.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

Mark,
I have always done the same with valve covers. However, I am trying to turn over a new leaf and rid myself of bad habits as well as curtail some leaks. the leaky cork valve cover gaskets were most likely my leak source but I will soon find out. My googling has revealed that many folks do it your way.

Right now I am re-doing brakes now that the valve covers are back on (torqued to 36 in-lbs) and I may dig into the steering to fix my always on door buzzer whenever the door is opened. I fixed it perhaps 10 years ago so it is easy enough to do. So, it won't be a while before I get the engine running.

Gary------


I have no information that the torque rating for the aluminum valve cover bolts is any different than that for the standard steel cover bolts. That torque is 55 lb/inches.

[Gary S.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

Hmmm, that is 4.6 ft-lbs which is on the high side of what I recall but still pretty light. What I wound up doing was to undo the bolts and put my 1/4" drive handle with the socket on it and did it "wrist tight". I then checked it with the torque wrench and it was at 4.

Thank you. I will do that number.

[Dan A.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

Gary,
Were you able to use the original valve cover bolts with these gaskets?
Thanks.

[Gary S.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

Gary,
Were you able to use the original valve cover bolts with these gaskets?
Thanks.

Dan,
Yes I was. My bolts original. And I'm guessing that they're about 1 and 1/8 inch long. The gaskets are only perhaps one sixteenth of an inch taller maybe one eighth? The bolts fit easily

[Dan A.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

Thank you very much!

[Edward B.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

In 1966, Justice Potter Stewart remarked about obscenity, "I know it when I see it." Here we are talking about 'hand tight,' and I know it when I feel it.

[Gary S.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

In 1966, Justice Potter Stewart remarked about obscenity, "I know it when I see it." Here we are talking about 'hand tight,' and I know it when I feel it.

What can I say! In full disclosure, I wasn't anything more than lucky with that technique.

[Jim T.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

Gary my 1985 Corvette GM service manual has a torque of 50 INCH POUNDS for the 1985's valve cover bolts. I don't remember seeing torque in my 1970's GM service manual so I use 50 INCH POUNDS.

[Gary S.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

Thank you Jim. I have found lots of internet comments but nothing in print. I am good to go now and will observe for leaks once I get it all out back together. I.went through all of my GM reprint manuals plus aftermarket manuals. Nada.

Gary

[Richard K.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

I watch a lot of Velocity TV programs, and I've noticed that the restoration/custom guys on these shows rarely use a torque wrench. I assume they use the torque "system" that I read or heard about many years ago called "mechanic's torque", which is, turn the screw/bolt until it seats and then give it 1/4 more turn. I almost always use a torque wrench, but I've often wondered how far off the "mechanic's torque" torque could be. In the case of compressing gaskets, would it work that well at all?

[Joe L.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

Thank you Jim. I have found lots of internet comments but nothing in print. I am good to go now and will observe for leaks once I get it all out back together. I.went through all of my GM reprint manuals plus aftermarket manuals. Nada.

Gary

Gary------


It's in the GM factory service manuals in the engine section of the "bolt torque" tables at the rear of the manuals. However, there is no distinction made between the type of valve covers. That means that the torque specified is the same regardless of type of valve covers.

[Gary S.]

Re: 1972 LT1 Aluminum valve cover bolt torque?

I'm not home now but the Service Manual was the first place I turned to before I started typing. Lots of torque values at the back but I really don't recall seeing anything for the valve covers. I will look again. regardless they're now sitting at about 45 to 48 inch poundsmk