Intake Sealant
Thread Starter
Le Mans Master
Joined: Jan 2001
Posts: 6,938
Likes: 1
From: San Diego CA
Intake Sealant
Just got my new BG 750 DP carb, Perfomer intake heat shield and all new fittings as per LARS BG paper to swap out that POS Eldebrock 1406 and Toquer II manifold.
I have swapped intakes 4 times and all had small leaks in the driver's side rear (different intakes, different cars). I do not use the gasket end pieces as Eldebrock suggests but I think the problem is not the end seals but my lack of drying time. I think if I left the sealant sit there for a few hours and then install the intake and torque I may get better results than the sealant just squishing out as it's torqued. Any guidlines as to length of time before torquing intake and whether you use sealant #2B, forget the damn manufacturer's name.
Oh Desert Dawg I will have hundreds of dial-up unfriendly pics for you when this is done. Can't wait to get her LARS tuned and see what she'll do.
I have swapped intakes 4 times and all had small leaks in the driver's side rear (different intakes, different cars). I do not use the gasket end pieces as Eldebrock suggests but I think the problem is not the end seals but my lack of drying time. I think if I left the sealant sit there for a few hours and then install the intake and torque I may get better results than the sealant just squishing out as it's torqued. Any guidlines as to length of time before torquing intake and whether you use sealant #2B, forget the damn manufacturer's name.
Oh Desert Dawg I will have hundreds of dial-up unfriendly pics for you when this is done. Can't wait to get her LARS tuned and see what she'll do.
Tech Contributor
Joined: Aug 1999
Posts: 15,197
Likes: 4,025
From: Connecticut, USA
I use Permatex RTV and let it sit until it starts to set but still is pliable to mold itself to the intake. Now if you look at a Permatex catalog or go to their web site you'll find a LOT of RTV they make,different colors some different characterists. Best thing to do if you're not sure call the customer service dept in CT and they'll help you out. I asked them last year why all the different RTV's why not just sell th ebest one? I was told the best one is the Gray RTV and used that on the last intake. Worked pretty good so far.
Gary
Gary
Senior Member since 1492
Joined: Aug 2000
Posts: 87,962
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
When I was putting my 454 together, I remember reading that when you apply the permatex, it's ok to assemle immediately but to wait 24hr for the blue permatex to "cure." Meaning wait 24 hr till you fire her up. Didn't matter to me and it makes sense since Permatex seems to be some type of silicone and that usually takes 24 hrs to seal.
No leaks here.
No leaks here.
Thread Starter
Le Mans Master
Joined: Jan 2001
Posts: 6,938
Likes: 1
From: San Diego CA
I just picked up the Permatez Ultra Black 2C and I'll call to get the cure time. I'm still waiting on some parts which gives me time to watch the tuner DVD which comes the Barry Grant carb. Between watching/ comprehending the DVD, making all the mods to both the carb and the bending/ modifying the Holley heat shield to clear the BG as per LARS instruction sheet that should take me about 2 days so it's a weekend project. Also I need to find a local shop with a 6an to 6an female swivel as someone on the Forum had told me the outlet of the Eldebrock filters are 8AN and it's not so I have a useless 8 to 6AN double female. 
Melting Slicks
Joined: Jul 2004
Posts: 3,248
Likes: 48
From: westland mi
Originally Posted by Jughead
When I was putting my 454 together, I remember reading that when you apply the permatex, it's ok to assemle immediately but to wait 24hr for the blue permatex to "cure." Meaning wait 24 hr till you fire her up. Didn't matter to me and it makes sense since Permatex seems to be some type of silicone and that usually takes 24 hrs to seal.
No leaks here.
No leaks here.
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Burning Brakes
Joined: Feb 2002
Posts: 752
Likes: 31
From: Melbourne Australia
David,
I know I'm stating the obvious.....but the parts have to be absolutely clean and free of any trace of oil. I use thinners on a small rag to thoroughy clean all the metal surfaces and my fingers then use Ultra Blue and allow to fully cure but usually a couple of days before firing up.....never had a problem.
Good luck,
Joe
I know I'm stating the obvious.....but the parts have to be absolutely clean and free of any trace of oil. I use thinners on a small rag to thoroughy clean all the metal surfaces and my fingers then use Ultra Blue and allow to fully cure but usually a couple of days before firing up.....never had a problem.
Good luck,
Joe
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I use only the perm black on the ends and only let it dry like it says till tacky.
The intake gasket use I only do spray red around the on the head side. light grease on the intake side. So I can quick change down the road. I hate having to use a pry bar and ding anything to get it apart miles later.
I've been fighting my Speed Demon 750 lately and about know everything what not to do. It's got every mod and every idea from "LARS" Nearly everything is new.
The most important thing--------- is set the pink cams P & S the same. From the factory the Primary cam was installed on the middle hole. Which leads to a delay in squirt. From day one this 750 Demon has had an off idle hesitation and I just dealt with it by wiggling the gas petal to kind of extra squirt through it.
It’s a must to set the P throttle blade to .020 on the primary transfer slot. Use the secondary throttle plate for idle speed.
I have 75P 81S jets .040 drilled out P squirters .125 air holes drilled in the primary throttle blades. 7.0 power valve. Polished down leg boosters. New .130 steel needle valves. Pressure set to 5 psi 1/2 wood thermal spacer. Mech pump with return line
The intake gasket use I only do spray red around the on the head side. light grease on the intake side. So I can quick change down the road. I hate having to use a pry bar and ding anything to get it apart miles later.
I've been fighting my Speed Demon 750 lately and about know everything what not to do. It's got every mod and every idea from "LARS" Nearly everything is new.
The most important thing--------- is set the pink cams P & S the same. From the factory the Primary cam was installed on the middle hole. Which leads to a delay in squirt. From day one this 750 Demon has had an off idle hesitation and I just dealt with it by wiggling the gas petal to kind of extra squirt through it.
It’s a must to set the P throttle blade to .020 on the primary transfer slot. Use the secondary throttle plate for idle speed.
I have 75P 81S jets .040 drilled out P squirters .125 air holes drilled in the primary throttle blades. 7.0 power valve. Polished down leg boosters. New .130 steel needle valves. Pressure set to 5 psi 1/2 wood thermal spacer. Mech pump with return line
Last edited by gkull; Oct 7, 2004 at 10:17 AM.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Originally Posted by foundvettelifeisgood
I put the varnish on the gaskets and heads, then put the black silicone on thick at both ends and around the water jackets. I don't recall giving it any curing time. No leaks.
thick at both ends and around the water jackets. I don't recall giving it any curing time. No leaks.