Problems w/ MLS HG's W/ PICS

chadder1313

Registered User
Well after a weekend full of working on this car, I finally got it running only to find out these Fel-Pro MLS Head Gaskets are leaking where the head meets the deck. They were torqued down in three different torque sequences. 35-55-75 ft. lbs. I started it and it idles perfect. It did miss for a split second and a puff of smoke came up from the bottom side of the engine. My guess to that was when the gaskets started to leak. This is the first time for me using the MLS gaskets and my assumption were that these are supperior to the composite gaskets. Can anyone shed some light here on this?
 
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I use copper spray on the block side only when installing on a non machined block surface and torque to 85ft-lbs. using ARP moly lube with ARP head studs.
 
Ok, this maybe a stupid question but am i able to re-torque them? Or do i need more gaskets. Does 10-15 ft. pds. more torque really make that big of a diffrence?
 
you removed the brass rivets that interfered with the heads when bolting down didn't you?

Also, there are alignment rings that sit into the block to align the head to the block when you bolt it down. I assume those were still in your block when you put the heads down?

I can't imagine what could allow coolant to leak out when things are torqued down properly unless something has gotten in the way of the heads seating properly
 
Ok that may be my problem. Rivets are the problem. So i have to remove rivets on these MLS gaskets? That means i have to get new head gaskets. Great. I cant win with this car at all.
 
I feel your pain but I always lokoed at it as a learning process...I still do now that it is time for tuning
 
Ok that may be my problem. Rivets are the problem. So i have to remove rivets on these MLS gaskets? That means i have to get new head gaskets. Great. I cant win with this car at all.

OH NO!!
You used the MLS but did not remove the rivets!!???
OUCH!!!!
 
True! It's totally my fault. I guess i missed the part that said CUT THE RIVETS out! I do know one thing I'm just going to go with SCP upper engine gasket kit and go with the composite's. I'm already over my budget on this build!
 
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Didn't remove the rivets on the MLS gaskets we used on my new motor. Dave was concerned that drilling them out could get particles of brass between the layers or stuck into the rubbery coating. If using head studs I like at least 90 ft.lb torque using APR lube. Dave doesn't like going over 80 because the threads on the block aren't very strong.

David
 
OK here's the situation, I'm putting composite gaskets back on the car. I am using ARP studs. Should i remove the alignment pegs? With the composites how should they be torqued?
 
I did not remove the rivets on my gaskets either, and had no leaks. The alignment dowels must stay, torque the composite gaskets to 90.
 
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Also remember that the deck and heads need very smooth finishes for those gaskets to seal properly.
 
That,s the answer

Also remember that the deck and heads need very smooth finishes for those gaskets to seal properly.
THAT IS WHAT IS NEEDED IF YOU DIDN,T DO THAT THEN YOU WILL HAVE PROBLEMS:mad: BTW I LEFT THE RIVETS IN AS WELL NOW:) BEEN DONE OVER 8 YEARS AGO WITH NO PROBLEMS :eek:BOOST TO 15 LBS :cool:
 
I didn't drill the rivets out. I used a snip, to clip the edge of the gasket that stuck out with the rivet and just bent it out of the way so the rivet dropped out. Only one of the rivets, on my motor, appeared like it could be an issue, so I removed it.

I only mentioned it, because if differences in castings from ford. If on someone else's motor the rivets interfere more, they should be removed. I would have expected someone to check that when bolting things up.

Just idling in your driveway, if you have the heads bolted down, it shouldn't leak. Of course, I'm assuming you used the Felpro Permatorque MLS Gaskets which have a black coating on them. If you used the Ford F150 gaskets that are just steel with no coating, I could see a possible issue if the block wasn't decked.

Are you certain it's the head that is leaking and not the intake manifold?
 
WHy would you think youde need to remove the rivets? I dont get it. Not like an head is going to hav ea receaver groove in them for teh rivets. I believ ethey are made to crush as they are brass no?

Regardless how are you so sure its your gaskets. DO a pressure test..Unless allot of smoke is comming out exhaust or water in oil.......A puff of smoke from under car means nothing..Could be anything As could a slight miss at first
 
Didn't remove the rivets on the MLS gaskets we used on my new motor. Dave was concerned that drilling them out could get particles of brass between the layers or stuck into the rubbery coating. If using head studs I like at least 90 ft.lb torque using APR lube. Dave doesn't like going over 80 because the threads on the block aren't very strong.

David

yeah i was gonna say I talked to dave and he said 80 with the ARP studs and I didnt remove rivets either and no leaks...I'm thinkin your gasket might have just been bent or something
 
WHy would you think youde need to remove the rivets? I dont get it.

The rivets on mine were interfering with the head, such that if left on, the head gasket would have had downward force applied to it at the rivet. (the head was touching it, the block was not).

It was close enough that I wouldn't be shocked to find another block where both the block and head were in the way.
 
sounds fishy . . .

The rivets that held together the gaskets I used were in no way interfering with the mating surfaces.
If there are rivets in between the head and block, I'd probably remove em carefully just for good measure.
I used F150 permatorque MLS gaskets that DID have a blue rubbery coating on them.
I think they were 4 layer, maybe 5, definitely not 3.
They cost $20ea less than the sc ones, all the coolant holes lined-up.
I sprayed copper spray-a-gasket on both sides of gasket and head and block.
You can't have too much sticky stuff keeping the water pressure and combustion pressure from leaking IMHO.
If you got 90 Foot-Pounds held by your bolts on the wrench, you're all set.
If you under-torqued em, take em off and spray em!
then re torque per instructions of the fastener, but end at 90, not 65 or 75 or whatever.
Hope I helped-ya!

paul
 
Im positive they are leaking from the heads where they meet the deck. I cleaned the deck really good because Ive heard about the MLS gaskets need a good clean deck surface. Now here's the thing, these heads have been resurfaced twice with one having quite a bit took off of it. My questions are: 1. Is it possible for me to reuse the MLS's? I ask this because they are only torqued down to 75 Ft. LBS. 2. Would that cause it to leak in the first place? 3. Do the alignment dowels and Rivets need to be removed?
 
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