90 350 intake gaskets and sealant

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I'm going to finally tear into my 90 raydo to replace intake gasket set. Has had a very slow coolant leaking onto the top of the intake.
Questions
Is Felpro intake set my best choice?
What type sealer should I use ?
 
The Fel-Pro set is really good. I like Hylomar M or Blue for around the coolant ports & Permatex Ultra Grey for the front & back sealing on the intake.

Be prepared for the old gaskets to be hard as a rock & stuck really good to the heads if original!!!
 
Looking like I may have trouble finding it locally. Quick search shows maybe our Harley shop has it.
 
Forma gasket is what I normally use but I am ordering a tube of m from Walmart tonight.
 
I used the Felpro set with the metal core when I did my 4.3. They seemed to have the best reviews at the time and I haven't had any problems since.
 
Thanks for the info fellas.
Sheesh hylomar is tough to find. 6 parts houses, 2 bike shops and granger. Gave up and ordered from amazon. It ships by seller so that is always slow.
Got enough to last a while though.
 
I get it from a industrial supply house in Dallas, Far to many use RTV for everything so demand isn't real high for premium non-setting joint compounds.

If I ever find the person that came up with putting RTV on O-rings......I'll kill 'em!!!!
 
Yeah I hear you on the orings.
I noticed that you don't really recommend hylomar for oil. I have been using right stuff for areas with oil . Have you had bad luck with hylomar and oil?
 
I use felpro gaskets and permatex "The Right Stuff" on the front and back if the valley.
It comes in a pressurized can like the cheese spread. Goes on easy and havent had any leaks in the 6 or 7 GM intakes I have done over the past several years.
 
Well.....I wouldn't use it for the "China Walls" on the ends of the Intake as it's about a 3/16" gap after assembly. If it was a close fit Joint style interface....I'd have NO problem using Hylomar!

GM used Permatex Ultra Grey as the recommended RTV for this application when they deleted the use of the leak prone rubber gaskets. Never got into the habit of using Right Stuff as I haven't had issues with Ultra Grey.

Also....RTV goes bad/hardens in the tube too quick for me to justify the cost of Right Stuff! If it came in a 3.5oz tube at reasonable cost....I might give it a try.
 
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Ok good info Thanks Cline I will use the ultra grey on this for sure as I will be able to let it sit for a day before firing it up. Just so I'm on the same page here. You do throw away the rubber china wall seals correct?
 
Originally Posted by P10crew
You do throw away the rubber china wall seals correct?


Yes, Throw them away!! I don't really understand why they're included.
 
I havent seen it in the parts stores, but Amazon has "the right stuff" 3 oz tubes for $8 or $9, and small 3 oz pressurized cans for $14.
The nice thing with it is it cures in 90 minutes, so by the time you have everything togeather, you are pretty much ready to fill up the fluids and drive it out of the shop.
 
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Spent about an hour on it today. No China wall seals in the set.
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What tool do I need to release this heater hose?
Irea
 
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