kaz1961

The valve cover on my 350 was leaking so I tightened up the bolts. They were quite loose and I tightened them pretty good. Now I am wondering if they should be tightened all the way or not? Is it possible to overtighten the covers?

Blue Ace

Yes you can go to tight. I would go with new gaskets and use a palm driver "like a screw driver handle" and tighten this way. After a hot run re-tighten. Check and make sure you did not bend your covers

Cali,68,L-79

This isn't a serious question is it?

bertmeister

Shop manual says 45 in-lb.

kaz1961

Not everyone is a mechanic. I am new to this and everyone was a beginner once. I was afraid to overtighten them and ruin the covers. Sorry if the stupid people of the world are such an inconveience to you genuises.

Gordonm

Yes it is possible. You can bend the steel covers and crush the gasket creating a worse leak. I just snug mine up. I have cast cover though.

2TONE82

Hey Kaz, good question...

To torque mine I warm up the car and use the smallest drive ratchet with a long extension. Then I tighten them using one hand, palm open. This snugs them up fine and no worries about bending anything. My '82 started to drip a little oil last month; thought I had a leaking oil pan gasket or rear main seal (low mileage car but things get old...father time can be as bad on a motor as uncle mileage) I too was surprised at how loose they were. No more leaks after snugg'en them up.

Jughead

You can snap the bolts off if you tighten too much.....real easy too.

Gordonm

Is that talking from experience

Jughead

But I'm a quick learner.

The Dude

Don't think you're out of the woods with a cast cover. I cracked a finned aluminum LT-1-style cover on my engine once. That was 'spensive.

Turbo-Jet

the trick is to get even clamping force, not excessive force which is a PITA to do because there are only 4 screws. (7 on BB does not help much...). too tight and you will distort a stamped steel cover and then you'll never get them to seal.

i use Loctite 242 on the screws as they will back off because i torque lightly (approx hand tight with a nut driver)

Brass Pass

Kaz-

I needed an answer to the same question about a month ago.

I found a list of torque specs at this site: www.torquespecs.com
It has alot of torque specs and other info that you might find useful sometime.

Good luck.

Jughead

Got a site for a Chevy BB??

Edzred72

I have always used the "thicker" 3/16" I think (not stock) valve cover gaskets and torqued to GM spec (45 in lbs). Never had leaks.
Eddie

gerry72

Depends on what kind of gaskets you use.

If you use a cork gasket, re-tightening them will do nothing but make things worse since a cork gasket swells to effect a seal. If the cover bolts are loose, you'll only end up splitting the gasket.

If it's a rubber composition gasket, you can snug up the bolts and have a chance at re-establishing a good seal.

But, in reality, if you have an oil leak in the cover gasket nothing but new gaskets are in order.

A couple of things on the gaskets... If you use a cork gasket it is installed without a gasket sealer (not to say that using a sealer will ruin things but if the surfaces are clean and straight, it's not necessary). Make sure the cover surface is straight (applies to steel covers) and flatten them if they are distorted at the bolt hole. Install the cork gasket and torque to the factory spec of 45 in/lb which is about the torque you'd get with doing it with a screwdriver. Using a socket on a plain ratchet will almost always guarantee you'll over-torque the bolts and crush the gasket/distort the cover and end up with a leak. Once oil hits the cork, the gasket swells and give a very tight seal. A phillips-head screw was commonly used on earlier assembly line smallblocks, which made it easy to have a good result for the DIYer in replacing the gaskets since it's pretty hard to over-torque a screw.

If you use a rubber composition gasket it's best to use the load spreaders under the bolts so that the load is spread across a wider portion of the cover rail. You have to use a sealer on the rubber gaskets since they only seal by initial compression and the sealer.

There are other cover gasket types, like the silicone-based gaskets and the ones that have the bolt stop and they are pretty much an upgrade over the composition gasket and have the advantage of being re-useable.

I prefer to use cork gaskets since, when done right, they will not leak as the swelling does a great job of accounting for surface irregularities.

Blue Ace

Here are the specifications Brass Pass mentioned.

Camshaft Sprocket-to-Camshaft Bolts 20 ft. lbs.
Cylinder Head Bolts 65 ft. lbs.
Exhaust Manifold Bolts Inner 2 Bolts on 350 cu. in. Engine 30 ft. lbs.
All Others 20 ft. lbs.
Flywheel/Driveplate Bolts 60 ft. lbs.
Intake Manifold Bolts 30 ft. lbs.
Main Bearing Cap Bolts 70 ft. lbs.
Main Bearing Cap Bolts (Outer bolts on engines with four bolt main ) 65 ft. lbs.
Oil Pan Bolts 10 ft. lbs.
Oil Pump Cover Screws 8 ft. lbs.
Rear Oil Seal Housing Bolts ( When equipped ) 135 inch lbs.
Rocker Arm Cover Bolts 4 ft. lbs.
Rod Bearing Cap Nuts 45 ft. lbs.
Thermostat Housing-to-Intake Manifold Bolts 30 ft. lbs.
Timing Chain Cover Bolts 7 ft. lbs.
Vibration Damper-to-Crankshaft Bolt 60 ft. lbs.
Water Pump Mounting Bolts 30 ft. lbs.

Brass Pass

Jughead-

I don't have anything for a BB. The guy that owns and operates the Torque Spec website will answer questions if you e-mail him. His name is Brian Bradburn and his e-mail is: Autospec@hotmail.com

If I come across a site for BB specs, I'll let you know.

Pb&j

dick...why be on a forum, just so tomake people feel stupid....do you never ask questions in your life, every question has an easy answer to the right person

Bikespace

What's the statute of limitations on bad forum behavior? I ask because this thread is 14 years old.