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Discussion Starter #1
My exhaust gaskets were leaking on my 460 with hardin logs. I replaced them with percys thick dead soft aluminum gaskets "spose to be the best you can buy" and they still leak. Do you think its the heads or logs that are uneven? I got the surfaces smooth before putting the new gaskets in.
 

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"Try it Now!"
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i machined mine flat, and use no gaskets with red silicone, haven't had a prob in several years.
 

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Weird, I used Holley dead soft aluminum gaskets with severly warped headers and the problem went away. :)

Guessing, it's the logs that are warped not the heads.
 

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Chances are the manifolds (and possibly the head exaust surfaces ) are "distorted" (Bear in mind that most of those manifold were designed to be "machined surface fit") if thats the case (warped) and especially if they've been already been machined once , it just seems to get worse (especially Ford and Olds) The gaskets we use and sell are silicone and metal impregnated and seem to work as well as anything , honestly if the sufaces are not flat and straight this will likely be a chronic and ongoing thing for you ,Call if we can help Tom
 

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E-7 Sheepdog (ret)
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In my case the logs were warped, not the iron heads. Going to have to have them machined flat before much'll work, and I'm one of the RTV guys.
 

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tintingsandiego
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i am on my second set of ford logs due to the same problem. from the info i got on my first set was that ford heads get hotter than most which cause warpage on most logs. so i bought a set of through bolt logs and you can torque these suckers down with a good gasket and no silicon. i havnt had a leak since. heres a pic of them on my 460
 

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i am on my second set of ford logs due to the same problem. from the info i got on my first set was that ford heads get hotter than most which cause warpage on most logs. so i bought a set of through bolt logs and you can torque these suckers down with a good gasket and no silicon. i havnt had a leak since. heres a pic of them on my 460
If your fortunate enough to find them , that "long Bolt style" right there are the "kind"
 

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Chances are the manifolds (and possibly the head exaust surfaces ) are "distorted" (Bear in mind that most of those manifold were designed to be "machined surface fit") if thats the case (warped) and especially if they've been already been machined once , it just seems to get worse (especially Ford and Olds) The gaskets we use and sell are silicone and metal impregnated and seem to work as well as anything , honestly if the sufaces are not flat and straight this will likely be a chronic and ongoing thing for you ,Call if we can help Tom
X2 Went through this with a 460 resurfaced still leaked had to replace the logs to stop the problem! Good luck!
 

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I just noticed today that mine are leaking water from between the log and snail. Any ideas? Do I have to use a certian type of gasket?

I have the logs with the long bolts on a 460 BBF and I used hight temp RTV in place of gaskets on the heads.No leaks there.

Thanks.
 

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Boat Nut
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Time for new gaskets, the manifold / risers are a bear to seperate. Might need to have the surfaces refinished, if corrosion has occured.
 

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Time for new gaskets, the manifold / risers are a bear to seperate. Might need to have the surfaces refinished, if corrosion has occured.
Thanks... Any idea who to order the new gaskets from? Or what type of gasket material I can use to make new ones out of?

Thanks
 

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Discussion Starter #15
I tried using just RTV with no gasket,it blew out in 20min. I could clearly see the manafold surface was warped at the ears to I plained it out. put a heavy bead of RTV copper on,I will try it in a few days to see if it holds.
 

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Boat Nut
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I tried using just RTV with no gasket,it blew out in 20min. I could clearly see the manafold surface was warped at the ears to I plained it out. put a heavy bead of RTV copper on,I will try it in a few days to see if it holds.

You need to surface the manifolds, don't need to be perfect, but no big gaps. When putting on the silicone lay on the bead let it skin slightly. Bolt the manifold on, leave it a little loose, and let it cure over night. The next day tighten the manifolds up.
 

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Thanks... Any idea who to order the new gaskets from? Or what type of gasket material I can use to make new ones out of?

Thanks
tony @skagen marine 253 939 8733
i just bought some for my hardin logs.
the gasket material is really thick.
i learned that all factory installed logs are done without exaust gaskets, just high temp silicone. the reason why logs warp is because of exaust gaskets.
ok ill bite!
having my logs machined, and installing without gaskets.
will see...................
 
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