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Max Wedge Intake plug seals?

uk-maxie

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We know we have a vacuum leak on our 63 Polara 500's intake so have got a gasket set ready to fit over the next week or two but are wondering what type of seals are supposed to be used under the 6x access hole plugs... can anyone here advise what's best to ensure they don't cause a leak too?

We bought a set of fibre washers which don't appear to be working. We've seen some for sale that are nylon - I cant see them giving a very good seal?

Nick Panaritis on his Nick's Garage YT video of him assembling a 440-based MW engine used what he called gaskets, but didn't say what material they are. He did stress that they are vital to stop vacuum leaks so must have worked for him.

Do they need some kind of non-setting thread sealant?

It doesnt help that on at least one, the top surface of the manifold where the plug goes in, isnt very flat nor parallel to the underside of the plug, when screwed in :rolleyes:

NB - we've just had the carbs refurb'd with new spindle bushes so we're pretty sure there's no leak there.

Grateful for any advice, thanks :thumbsup:

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Thanks for the quick response guys.

Doug - do you know what size o rings you used? Or were they just sized to fit snug under the plug head?
 
Rubber o-rings on my max intake too. I have no idea what size, but they are a VERY snug fit on the plug. They are definitely stretched over the plug.
I have never had to change them.
 
Last edited:
Rubber o-rings on my max intake too. I have no idea what size, but they are a VERY snug fit on the plug. They are definitely stretched over the plug.
I have never had to change them.

Thats good to know, thanks
 
I think I remember being told that those intake plugs are the same as drain plugs on Dana 60's. Could this be right?
 
Thanks for the quick response guys.

Doug - do you know what size o rings you used? Or were they just sized to fit snug under the plug head?
They fit snug and like 3/32"-1/8" thick.
Doug
 
like everybody above says, use o-rings. u wont have to Over tighten them to stop a vacuum leak like other versions .. i took 1 of my plugs down to ace hardware and matched it up to get the right 1...
 
They fit snug and like 3/32"-1/8" thick.
Doug
I have no idea if mine are original replacements, or not, (much too nice condition to be 60 yrs,old) but I think mine are at least an 1/8". If memory serves (I'm 250 miles away),they are thicker than that, but certainly not 1/4.
1/8 ring will most likely work.
 
Might want to lightly lube them. Make sure the surface of plugs and manifold are burr free. Had one o-ring stick and was misshapen. I went to nylon ones like 65hemi, no issues. Nothing against o-rings.
 
Wow, you can tell I've worked around German cars for too long! My brain immediately said aluminum or copper! But, I've never had mine out.
 
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