Intake manifold gasket...which one to use???

[valveamp]

Hi. Here's my situation. About a year ago, I replaced my stock intake manifold and 2-bbl carb with an Edelbrock aluminum manifold and 4bbl carb. At that time, I used the Fel-Pro "performance" 1250 intake manifold gasket. I had a major coolant leak out the back passenger side of the engine and inside into the oil as well. I replaced the gasket with the "stock" Fel-Pro gasket (from Napa) and tried again. I've been losing coolant, slowly, ever since. Last week, I noticed "wet" grease on the back side of the engine on the passenger side. I cleaned off the grease in that location and drove the Bronco. After rechecking, I see what looks to be a wet area down the back of the engine coming from the intake manifold area. No evidence of any water in the oil, that I've seen. My question is, I've read that the Fel pro 1250 is for aluminum intakes. Should I try that again? I've read of other problems with the 1250, but many comments say "they are for aluminum intakes". Maybe I just did a bad job of installation the first time. By the way, I did not use the cork end gaskets in either installation. I also have a tiny oil leak at the front, where it drips down on the top of my water pump, passenger side. I'd like to hear what you guys with aluminum intakes have used that worked for you.

Thanks,

Jim

 

[70_Steve]

I tried the 1250, thinking I could do a "better" job of installing it than other people. It lasted about a year, then I had a trickle of antifreeze down the front of the passengers head, coming from the coolant port on the intake. Lucky it leaked outside the engine!!! When I pulled the intake to replace the gasket I saw where the gasket had crept away from the coolant port, as well as a couple other places.

I went with the same stock Felpro gasket you did. The one with the steel core. On installation I probably retorqued it 10 times before starting the engine, and had to take up a little on a couple bolts each time as the gasket relaxed. Then retorqed again after starting and letting it heat cycle. It lasted two years, until I bent a connecting rod and had to pull the engine apart again. But the intake gasket looked perfect.

 

[Viperwolf1]

I also had leaking problems with the 1250 gaskets. There is a 1250-S with a steel core and that is what I've been using for the last 3 years or so. Last winter the coolant leaks started again. I have a set of edlebrock 7220 gaskets that will be going on soon.

 

[75junebug]

Good cleaning and good quality black or red rtv around the water jackets is the key to sealing these up for good. I even "score" the surfaces on the intake watrjackets with a blade before applying the rtv. There is a "head side" surface on the gasket, and there is a different set of gaskets for the 5.0 EFI manifold. If I remember right, the EFI gasket installed on a factory or Ebrick performer manifold does not have enough sealing area around the water jacket that can lead to a leak externally and internally. When I was fighting head machining issues, I went thru 6 Felpro upper gasket sets, all had blue intake gaskets(reg carb apps) and black ones(5.0 EFI apps) Directions were not very clear.... you prolly know this already, can the valley rubber seal, use a good thick bead of super black rtv...

 

[Bronco73]

Not sure if this an issue any of you speak of but isn't there a difference in the ford heads requiring a different gasket? I forget the year the water jacket design changed but I do recall it causing issues in the past.

 

[blubuckaroo]

After Federal Mogul took over, the quality of Fel Pro went south. After a huge amount of bellyaching from the Mustang clubs and then from Ford Motorsport, they developed the 1250S3. It's got a steel layer laminated in to keep it from pulling apart. So far so good.
And...You 351W guys aren't immune to this mess. The Fel Pro 1262S3 replaces the Fel Pro 1262.

 

[valveamp]

So, you would recommend the 1250S3 Fel Pro gasket for an aluminum intake manifold? Summit has them for $27 in stock. Hopefully, this will solve the problem. Thanks.

 

[mattt]

I've had good luck with Fel Pro MS95952 gasket kit. It's a stock type gasket and comes with lower manifold gaskets & an upper to lower GT40 gasket. No leaks thus far.

 

[Bronco73]

Its been so long since i have changed a SB intake gasket I never knew there was this much trouble with the gasket material.