# valley pan bolt torque specs



## JohnGoat (Aug 21, 2015)

Re-installing valley pan on a 455, found two different torque specs online, one said 15, one said 10. I went for 10, and the area around the front bolt sank a little, while the area around the rear bolt sank a lot. It slightly dimpled the rear pan lip. Seems like the torque specs might be wrong? Have I ruined the pan?


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## PontiacJim (Dec 29, 2012)

Good question. Looked through my '68 service manual and another Pontiac engine book and no value's were found other than "install push rod cover." However, I did find in the Chilton book a chart for bolt size & torque values. Can't remember off the top of my head the size of the bolt, but this may help, here goes:

Grade 5 Bolt dia 1/4" dia, 3/8" wrench, - 7 ft lbs. Less than grade 5 is 5 ft lbs.
Grade 5 Bolt dia 5/16" dia, 1/2" wrench, - 14 ft lbs, Less than grade 5 is 9 ft lbs.

I don't think I ever torqued mine. Just used sealer (I like to use the Indian Shellac on it -old school sealant and it sticks like glue!) and snugged it down. You don't want to crush it. You might put a little Loctite blue thread locker in the bolt threads as this will keep them from backing out. The bolts on my 455 has small thin washers under the heads to create a seal over the valley pan holes they go through. May want to put a dab of sealer under the bolt head as well.


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## Pinion head (Jan 3, 2015)

Have to be VERY careful tightening those two bolts up, they can bottom out into the OD of the cam bearing. I always run a little thin washer on the valley pan bolts.

The torque spec is only 3 1/2 foot lbs (42 INCH/lbs if you have a handy dandy dial type inch lb torque wrench). I originally was taught the valley pan bolts can be lightly tightened and once the head of the boot touches the stock steel valley pan, should take no more than one turn.


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## JohnGoat (Aug 21, 2015)

That's what I thought, and I've probably ruined the pan. Wouldn't have been so bad if I had stopped at 5 lbs, since I went in increments. But the corners where heads meet block just didn't feel like a smooth transition due to protruding bits of head gasket, so I thought some tightening was necessary. In retrospect, some extra gasket sealer probably would have been enough. Should I try to trim the head gasket bits?

I did note that the bolts could bottom out against the OD of the cam bearing races, so I trimmed the bolt ends down. I also added some sealer under the thin washers. Seems I had all the bases covered except for that torque spec.

I've noticed that many replacement pans are just a single layer of metal with no oil baffles for the PCV valve. So maybe that's what the torque spec was for? Otherwise I can't think of a single good reason for torquing them.


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## geeteeohguy (Feb 2, 2008)

No tighter than nut-driver tight, or 1/4" drive tight...just snug. A kid I used to work with tightened his to 45 foot pounds....and destroyed the valley pan as well as breaking the boss in the engine block. Common sense here: you don't tighten valve covers to 5 foot pounds of torque, do you? All sheet metal parts need to be just snug....no more.


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## Pinion head (Jan 3, 2015)

There are kids and there are BIG kids, typically both do a LOT of damage wrenching. My favorite are big kids that think they can r/r parts in a differential, and have the idea, with the help of a youtube video, it will take the same level of skill as swapping out spark plugs...

Another simple problem point I've run across with casual wrenchers is over tightened accessory belts. Over tightening of the accessory belts will eventually lead to a worn out waterpump bearing and occasionally, a wornout PS pump bearing. A belt tension gauge is a good tool investment if one does a lot of own maintainance work, but don't turn wrenches everyday.


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## geeteeohguy (Feb 2, 2008)

Amen to that. Where I worked, about 30 years ago, we hired a college certified apprentice who had every certificate in the book. After snapping off all the bolts in a small block Chevy engine at least twice, she got the axe. Had absolutely zero 'feel' for wrenching and no common sense, either. Was bottoming out bolts and tightening them to about 150 foot pounds of torque. Broke bolts, stripped threads, smashed gaskets, etc. Had no business wrenching on cars. Personally, I use torque wrenches on engine internals, transmission internals (autos), diffs, and the like. I haven't used a torque wrench on the outside of an engine or the rest of the vehcile for decades. No need to.


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