68EFIvert

Well I completed the blower conversion and had it tuned. When I picked it up from the tuner he said I had a fluid leak and it was coming from the back of the engine. He thought it was a heater hose or something. I thought it was really weird since the hoses are new. I suspected it was the head gaskets leaking.

Fast forward 2 weeks to today. I stopped by the body shop to check on progress and there was a bunch of antifreeze on the ground under the car. I felt the back of the engine and there is fluid by the heads and block. I think it may be my Mr. Gasket MLS head gaskets. I am wondering if my junk yard 5.0 block did not have as straight of a deck as the machine shop thought when I had them bore it and check it out.

I can think of a couple options.
1) take the heads off and replace the MLS gaskets with FelPro 1011-1.

2) take off the upper intake and valve covers to see if retorqueing the bolts fixes the problem.

Do any of you guys have experience with MLS gaskets and if so can you give me some advice? I went with them because of the blower. I am running about 10 lbs of boost and the AFR guy said the FelPro 1011-1s would be good up to 12 lbs.

my77stang

could be the intake gasket on the back of the heads......

but......

why in the hell would you use an MLS gasket with a blower and NOT get the block milled?

68EFIvert

I never planned on the blower when I had the machine work done 2 years ago. You know how it progresses with these things. I looked at it another time and noticed a plug on the flat portion of the block behind the intake. It is threaded but does not have a plug. It was filled with antifreeze. Maybe my problem is simple and I need to plug this? Do you guys know what that hole is for/goes to? Thanks for the help.

silver91gt

mls gaskets require the heads and block to be a certain smoothness

my77stang

yeah mls gaskets need a finer deck surface but usually by the time a block has been tore down, wire wheeled, sanded on, or anything else the smoothness is there..... its the fact that the deck surface isnt flat thats the problem.

our shop decked every single block for every motor we build (stock replacement motors mostly) and they were always warped. less than the heads usually were, but always warped. i know this because i've decked hundreds of blocks myself.

68EFIvert

Well it looks like I am going to pressure check the system to confirm my theory but it sounds like it is right. It looks like I know what I will be doing this weekend. S&%T!!!!

aode08

check your oil, make sure your not running coolant in the block.

67mustang302

Cometic makes a nice head gasket.

only90s

True, but my Cometic MLS still seep a tiny bit....Cometic told me to run Radiator Sealer through my engine to stop it [sm=boosign.gif]....

uedlose

I run the Fel-Pro mls on my wifes car it dont leak water but it leaks oil some at the heads. I run the Cometics on a customers car no leaks yet but I did put stop leak in the rad.