Cam Tower End Plug Sealant?

[Jubbie]

Folks,

Should I use any sealant when I install the cam tower end plug?

Thanks

[snowman]

I use red locktite. However since this is a true press fit, no sealant should be required, at least in theory.

[ChrisBennet]

From my admittedly bad memory, I think the pre '89 factory manuals say to use antisieze. The manuals for the 964 models now advise using sealant I think.
-Chris

[Jubbie]

Red loctite = Loctite 271 or Loctite 574.

Don't want my limited appriciation of the color pallet to cause a puddle under my rebuild

Thanks

[ChrisBennet]

I'm taking a break from um "modifying" the cat on my 944. A ***** of a job it turns out.

My '84-89 Carrera manuals say to: "Coat new plug with Optimoly HT and press in plug."

My 964 manual (printed in '91) say almost the same thing: "Coat new lateral plugs with Optimoly HT and press in plug."

Optimoly HT is basically antiseize.

Remember what I said about my memory? I was remembering the wrong part: The centering pin (which holds the spray bar in place) is installed with Loctite 270 (aka "red loctite"). According to the Loctite documentation 270 is "Intended for parts that do not require disassembly. Cures fast and reliably on most metal surfaces. Seals threads against industrial fluids."

There is another Loctite product that is sometimes used on 911 motors and it also red in color - Loctite 518. 518 is a sealant that comes in a tube. It is not referred to as "red Loctite" even though it is red. I've used for sealing between the head and cam carrier.

Hope that helps.
-Chris

[john walker's workshop]

common permatex aviation sealer, aka brown camel snot. the end plug is just a basic "soft plug".

[Jeff Alton]

Brown snot! LOL that is a good description!!! That stuff seems to end up all over my sleeves too!

Jeff

[Fishcop]

And if you've ever played with camels you'll know how good a description that is!

[snowman]

I have had to make my own plugs to replace the factory ones. All seem to be slightly differen't in size, by a couple of thousands of an inch or so. I make the replacements with an interferance fit of one to two thousands of an inch and press them in. NOTHING should ever leak by them, with or without any sealant.

I am not familiar with factory replacement plugs, are they even available? If so how tight do they fit?

[ChrisBennet]

[Jubbie]

OK,

So when I was talking about the end plug, I was talking about the 901.105.161.01 big plug that is the same diameter as the cam bearing. Was this what you guys were talking about sealing?



Thanks

[ChrisBennet]

Originally posted by Jubbie
OK,

So when I was talking about the end plug, I was talking about the 901.105.161.01 big plug that is the same diameter as the cam bearing. Was this what you guys were talking about sealing?



Thanks

No, not that plug. Where talking about the little plugs that go in the ends of the spray bars.
-Chris

[snowman]

Chris,

The Stoddard plugs, are they made by Stoddard? In any case how tight do they fit?

Jubbie,

Sorry for my confusion. For the big end plug, the brown camel snot. or more available Ford brand snot works fine.

[ChrisBennet]

Originally posted by snowman
Chris,

The Stoddard plugs, are they made by Stoddard? In any case how tight do they fit?

Jubbie,

Sorry for my confusion. For the big end plug, the brown camel snot. or more available Ford brand snot works fine.

Jack,
They are a Porsche part. I can (and do) just tap them in without freezing them or heating the cam tower. They tap in snuggly. I don't know if that describes the fit very well but it's the best I can do. If you know the hole diameter I can measure a plug and we can figure out the press fit amount.
-Chris

[snowman]

My range of experience on the plugs is limited, but the variation I have seen so far is about 0.003" or +/- 0.0015". Using a single size replacement makes for a very tight press fit to a "loose" same size fit if one chooses the largest hole and a plug that can still be pushed into the smallest hole. Maybe the heads I have seen have been reworked before and consequently have slightly larger holes as a result.

I size my homemade ones so that a small ring of aluminum peels off the plug as it is tapped or pressed in. Thats an interferance fit of 0.0015" to 0.003" with 0.002" nominal as a goal. The "ring" dosen't form well due to the aluminum head so its more like a mushrooming effect on the outside end of the plug.