Replaced Gasket... It Still Leaks.

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Don't bother with Permatex (the black sticky stuff). Its fine for sealing water pumps but not exhaust manifolds. Some of the high temp RTV's will last a little while but they are just a bandaid for quick fix. Materials that are designed for high temp apps like Grafoil or steel shim gaskets don't need to be retorqued. Make sure the manifolds are flat or you're just wasting your time. Is the leak on the intake or the exhaust? If its the intake, are you sure you don't have a crack in the floor of the intake below the carb?
 
well from what i can see its on the exhaust. the intake and exhaust are flat and i know i dont have a crack anywhere.
 
MWalls, do you have headers, or an exhaust manifold? (Sorry if I forgot, and you mentioned it already.) If you have flat stock manifolds, your problem seems really unusual.
 
it is a manifold. i am begining to wonder if it has the right intake and exhaust manifold on it. i have a leak on both exhaust and intake but the exhaust is really bad
 
You might try seating the manifold assembly against the head with no gasket in place. Snug the bolts but don't fully torque them, then go around with a thin feeler gauge (or aluminim foil) and hunt for a warped or hollow spot. A standard gasket should be able to deal with a 0.003-0.005" gap as long as its not really narrow - like a crack. Another thing that might be worth trying is spray the flange of the manifold with Dykem (or any light spray paint) let it dry, then slide it a on a flat surface like a mill table, or table saw and look to see if some unscratched paint might point out a hollowed spot. Lastly, are the manifolds close to original for the engine? Like 2F manifolds on a 2F engine - maybe the ports really don't line up well enough to make a great seal. The maniflod bolted to the head without a gasket in place might point that out. HTHs. Keep us posted.
 
Maybe you could have the wrong manifolds. That would explain it. How many studs?
 
6 studs. i probably should take a pic and post it
 
ok, please allow me be a smart a$$ here. my reason for being one: auto parts store owner for 28 years (retired) (sold only to the professional shops for 20 years), sold fel pro, victor, mccord,Detroit, bec, itm gaskets to mention a few. just purchased a 72 fj40 with the stock f engine with intake sealing issues. It had the Felpro MS 22813 gasket on it at purchase ..........the port size in the fel pro gasket was to damn big to seal .......during the years from 1969 to 1974 there were three different combos of intake/exhaust port sizes used....for my port size I had to use the oem gasket #17172-60031 to get a seal......NOT saying that is the one you need. You MUST start off by matching the port size of the gasket to the head and then to the size of the port in the intake manifold or by finding the production date of your engine and getting the gasket for that engine and only for that production date engine.....I could have gotten a free felpro gasket..........BUT I had to spend $21 at the dealer to FIX the leak.........there is nothing wrong with the quality of felpro.....its just the port size is to big for some of these engines in these year models.........this is the technical support number for felpro gaskets 1 800 325 8886 (or was a couple of years ago).......now for the exhaust header......these after market headers were made with a "universal size port opening".......use a ample supply of high heat rtv and/or a gasket that fits the port opening of the header and hope that seals the exhaust or have a adapter shim plate made to match to the ports.....all of the post about machining the surfaces flat and torque are relevant as well........... :cheers:
 
[quote author=crossbones link=board=1;threadid=9326;start=msg83909#msg83909 date=1073140974]
ok, please allow me be a smart a$$ here. my reason for being one: auto parts store owner for 28 years (retired) (sold only to the professional shops for 20 years), sold fel pro, victor, mccord,Detroit, bec, itm gaskets to mention a few. just purchased a 72 fj40 with the stock f engine with intake sealing issues. It had the Felpro MS 22813 gasket on it at purchase ..........the port size in the fel pro gasket was to damn big to seal .......during the years from 1969 to 1974 there were three different combos of intake/exhaust port sizes used....for my port size I had to use the oem gasket #17172-60031 to get a seal......NOT saying that is the one you need. You MUST start off by matching the port size of the gasket to the head and then to the size of the port in the intake manifold or by finding the production date of your engine and getting the gasket for that engine and only for that production date engine.....I could have gotten a free felpro gasket..........BUT I had to spend $21 at the dealer to FIX the leak.........there is nothing wrong with the quality of felpro.....its just the port size is to big for some of these engines in these year models.........this is the technical support number for felpro gaskets 1 800 325 8886 (or was a couple of years ago).......now for the exhaust header......these after market headers were made with a "universal size port opening".......use a ample supply of high heat rtv and/or a gasket that fits the port opening of the header and hope that seals the exhaust or have a adapter shim plate made to match to the ports.....all of the post about machining the surfaces fl
[/quote]

Boy, are you gonna come in handy :D
 
Right number of studs. How many holes (for the manifolds, not studs) in the gasket? 7 or 9? (should be 9)
 
Crossbones went where I was headed. :cheers:
 
here are some pics of it.
 
another
 
In the second pic, it looks like the exhaust manifold is missing the tab for the bolt near the water pump. There is a hole on the head that matches up with the hole in the gasket isn't there? Is the other end of the exhaust manifold, near the firewall, missing the outboard bolt also?
 
That explains it. You have the wrong gasket AND (I think) the wrong manifold. The gasket is for 8/76 and up. The manifold is for 1/75 to 8/76. Depending on your month 74, this is how it should look.
 
well that looks like my intake. i just ordered gaskets from specter, it will probably be a few weeks before i can work on it again.
 
It's the exhaust that is a little different. What month 74 is yours?
 
i am not sure what month mine is where can i find that at. i think i just had the wrong gaskets all together because of the gasket between the intake and exhaust is a little thick. which could be making my exhaust leak around the top of the gasket.
 
There is (or was) a plate on the driver's doorpost that has the month and year of manufacture, and IIRC one on the passenger side inner fender says too. Finding that date will help you get the exact gasket.
 
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