Post by: paklein on June 30, 2006, 12:00:00 am
I have a 78' C-10 work truck that I did a motor swap in awhile back and have perpetually leaking valve covers.
The original 305 motor dropped a valve and I got a long block 305 from NAPA and did the swap. Used the valve covers from the original motor, and they leaked. Tried replcing with a couple of different gasket sets with no luck. Went as far as replacing valve covers, but still no luck in stopping the leaks.
I was told by somebody that this is a common problem due to the fact that these valve covers only use 4 bolts to hold them down.
What can I do to solve this problem? Kind of embarrassing pulling up to customers' houses and have smoke pouring out from under the hood......
Any help would be appreciated
Paul
Post by: Lt.Del on June 30, 2006, 01:04:00 am
Get yet another set. Put two sets of valve cover gaskets on her at one time. Doubling the gaskets will improve seal--especially if they are warped.
A couple of hundred miles after installing them, ensure you retighten the cover bolts once more. Don't overtighten though, they will snap. YOu can get some of those chrome type of brackets that tighten down under the valve cover bolts....they are like two inches long and presses down on the valve cover in two places after you tighten each bolt down.
SgtDel
aka "Andy"
www.delbridge.net
1979 Big 10 383 stroker
1991 Blu 'Burb 3/4 ton 4x4
Post by: autonuerotic on June 30, 2006, 02:55:00 am
>>>>>Smear some silicone on the face of the gasket, dont just gob it, do it liberally and place it on one of the valve covers (do the same for the other side.) Let the silicone set up for about 2-3 mins, next find somewhere flat and out of the way like a workbench. Set the valve covers onto the flat (clean) surface gasket side down, while making sure that the gaskets are not disturbed and the holes still line up. If the gasket moved a little use one of the bolts or t-bolts to line back up the holes. Place the plywood over the tops of the valve covers and set the wieghts on top, or books and let it dry over night, then install them when you have time. There is no need to put silicone on bottom of the gasket when you install the valve covers (some people do that.)
>>>>>I had a similar problem years ago and did what I have just described, its been two engines and seven years and I still have the same valve cover gaskets with no leaks. A heads up...Some people put too much silicone on something and dont let it set up a little, so when they install it especially valve covers the silicone will act like a lubricant and the gasket may slide out of place. If you are using bolts or studs, just snug them you do not have to crank on them. Double gaskets is not a bad option either, but be careful that may cause a leak too. Hope that helps and good luck!
Post by: Blazin on June 30, 2006, 06:35:00 am
Post by: VileZambonie on June 30, 2006, 12:59:00 pm
Post by: paklein on July 02, 2006, 01:27:00 pm
Paul
Post by: 1976Scottsdale on July 03, 2006, 06:20:00 pm