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RIP (12/27/60-7/18/15)
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When I tighten the valley pan down, it looks like not much, if any of the gasket on the bottom sides is going to contact the block or heads.
Should I just remove it? Or trim the width down?
What is the best way to ensure it seals properly?
thanks as always
 

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Before putting the gasket on, put the valley pan on without gasket and check to see if there are any gaps between the lip of the valley pan and the heads and front and rear of the block. It is VERY important to fit with out gaps. After it is flat with no gaps I use Permatex High Tach Sealant to glue the gasket to the pan. Then I put a thin layer of RTV sealant on the heads and front and back of the block where the gasket will sit. Torque the bolts to 15 ft lbs.
 

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Before putting the gasket on, put the valley pan on without gasket and check to see if there are any gaps between the lip of the valley pan and the heads and front and rear of the block. It is VERY important to fit with out gaps. After it is flat with no gaps I use Permatex High Tach Sealant to glue the gasket to the pan. Then I put a thin layer of RTV sealant on the heads and front and back of the block where the gasket will sit. Torque the bolts to 15 ft lbs.
:agree Making sure the shape of the cover fits the contours of the block and heads is very important to get a good seal. If you've got a round nose pick body hammer, it's a little easier but a plain old ball peen hammer will work too. Just set the cover on the block without a gasket, start the bolts enough to keep it from moving around on you, and work your way around the edge of it, fitting it to the block/heads by tapping the edges with the hammer as you go.

Another tip: before you put the gasket and pan on, dab some silicone sealer in the 4 "corners" of the block where the heads and block meet, enough to fill those little gaps. Let it set up for at least 30 minutes before you continue. Sometimes you can get leaks in those little gaps, especially if for some reason you're having to run thicker than stock head gaskets.

Before you insert the bolts, dab some silicone sealer underneath the bolt heads to help seal the bolt holes in the cover.

Tighten the cover down slooooowly. Sometimes tightening it will tend to push the gasket out, especially on the long sides on the heads. If that starts to happen, just stop and use a wide, flat tool (like a big bladed screwdriver) to ease the gasket back under the cover. Then continue.

Once you've got it tight and you're happy with it, it doesn't hurt to dab some more sealer around the circumference of the bolt heads to seal them to the cover.

Bear
 

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We don't "glue" real cars together. A "half a tube" is enough for 4 engines. A THIN bead (about 1/8") is called for. Too much "bubba-cone" can cause issues with the oil pump and filter, if it "gets in there".

Apply a bead around the entire "border" of the valley cover. After about 5 minutes (allow it to "skin up"), carefully lay the gasket on the cover and press it into place. Allow it to dry over night. THEN, bolt it down. Follow Bear's suggestion for fitment.

Jim
 

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I agree with Mr P Body 100%. A tiny dab will do ya. I had a 428 over 20 years ago that someone had put together with a ton of blue silicone. It had major oiling problems. Tore it down and found silicone chunks in the oil pickup, oil galleys, and everywhere else. A little goes a LONG way.
 

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We don't "glue" real cars together. A "half a tube" is enough for 4 engines. A THIN bead (about 1/8") is called for. Too much "bubba-cone" can cause issues with the oil pump and filter, if it "gets in there".

Jim
well you know what. i have a real car. and the half a tube thing was a bit of an exaggeration. you sure know your stuff but just about everything you have said to me on this site has been rude
 

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I just read this and found it extremely informative Bear and P-body. I am just about to do this to my 389. So i will be adhering both pro's advice. Check fit, adhere gasket, rtv corners, bolt down "slooowly". i'm ready for some happy motoring. Cheers!!!
 

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skip RTV on vintage engines. If you use gaskets, RTV has no place but on the intake around the front water passages only and just a thin layer. Or at the corners of the oil pan and front lower edge of the timing cover. Not on the valley pan. There is no need once the gasket is glued first to the valley pan to hold in position, just like valve cover gaskets. RTV will screw up an engine if it gets in the wrong places which is usually the case, it is not gasoline resistance.
 

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I used rtv to hold the gasket down last night. P-body's instructions were spot on. i will be installing tonight. I will also be checking clamp-down to the heads and block using a piece of paper to check gasket contact to block and heads. I may just have the old girl running again tonight!
 

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i put the valley pan on last night and it started folding up when i tried to put 15 lbs to it. i checked contact all the way around and it had good contact at like 8 or 9 lbs and progressivly got worse as i tightened it so i left it at 8 lbs. if it leaks i guess i will try again. hopefully she roars tonite!
 

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Most tin should be brought down till it makes contact. Then tightened till the gasket compresses but not squeezed flat. It should be torqued in Inch Pounds. I never torque them tho. I go by feel of the bolt being tightened and watch that the gasket isn't getting pushed out. It is a fine line between, enough that the bolt will not back out, and leaving enough room for the gasket to seat properly. Over tightening will dent the tin at the bolt holes causing it to not be flat and even pressured on the gasket. I have never understood why the tin from the factory did not have a better or thicker flange. New cars for the most part have aluminum covers with much better machined and thicker flanges.
 

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:agree - Torque spec on those bolts isnt' important. It's more of a "feel" thang. Another trick is to dab a small bit of silicone sealant under the bolt heads before you install them to help prevent oil from splashing up around the bolts. Don't go crazy with it.

Bear
 
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