i have read on a few threads about people dimpling the intake or the block to fix the leak on the back of the manifold between the block and manifold. would anyone by any chance have pictures of this or instructions/tools to use to do this.PLease Help!!

 

yeah i'd like to know that too, my LT1 leaks like that's its job!

 

I just used a small file and made some thick X's a few inches apart on the front and back of the block. Wouldn't go extremely deep or take the X through the edge of the block. This is done to "rough up" the surface to give the RTV a little (probably very little) extra holding power. I would also recommend using "The Right Stuff" its black RTV that you can get at any Napa.

 

A hammer and a punch will make dimples. If you use a file to make a line, don't extend the line to the edge or you just give oil a passage to possibly leak out.

 

when i use the punch how far apart should i make the holes?
with the file how many x's should i make and also are you talking about using the corner of the file or laying it flat on the surface just to scratch it?

also should i put the dimples on the intake or on the block its self

one last thing when i put the silicone on the block should i put it on the inside or the outside of the edge or just make a fat bead that covers it totaly

pictures would be awesome.

 

You put the RTV in the middle. (I may have used a bigger bead than was actually needed). There are dimples under that RTV and on the manifold.

 

Thanks for the help i appreciate it.
Is there a reason you used copper insted of black? or is that just what you had around?

 

The copper is the most heat resistant. Heat from the EGR pipe on the rear of the intake manifold is suspected in being a contributor to the infamous intake manifold leak.

 

is the permatex orange high temp rtv the same as copper ???

 

How long did you guys let the RTV bead before putting the intake on? My motor is on a stand, so I am not too worried about having any line up issues.

Thanks:

ZMAN

 

Nope. The Ultra Copper has a higher rated temp range.




I did not wait for any curing before putting the manifold on. I feel it is going to seal/stick better with the sealant "wet".