Epoxies for intake port use...

[cjshaker]

I need to find a good epoxy for some intake port use and was wondering what the best type to use is. Most of the ones I've seen have a greenish or yellow/tan tint to them, but I have no idea what they are or where to get them. What do you guys recommend?

[Barry_R]

We use an industrial "A and B" packaged by Moroso when we want something that is very stiff in working consistency.  Good when you want a particular shape that stays in place as hand formed.

We use "Splash Zone" marine epoxy when we want something more fluid and easier to mold/shape/pour.  Better when you are filling a floor or trying to blend a contour.

[Drew Pojedinec]

I've probably used 20 gallons of splash zone in my life....
It is good stuff, we have actually poked a hole in a boat and stuffed it with splash zone and ran around for a bit before a proper hard repair was made.

Pro-Tip
Get an old coffee can or bucket, fill it with water.  Dump your amount of splash zone yellow in, dump in an equal amount of the black.  Mix and mold it by hand in the water if possible.  When totally mixed use.
If you try mixing it dry it's a horrible mess, and if wearing gloves, you WILL get them stuck in the ball of splash zone.  It will remain usable for a good little while in the water but will eventually set up.

[jayb]

X3 on Splash Zone.  You can get it at go2marine.com.

[cjshaker]

Thanks for the replies, guys. I'll go ahead and get both, but will likely need to use the Splash Zone. I need to partially fill an intake port and taper it to match a head port.

[cjshaker]

Pro-Tip
Get an old coffee can or bucket, fill it with water.  Dump your amount of splash zone yellow in, dump in an equal amount of the black.  Mix and mold it by hand in the water if possible.  When totally mixed use.
If you try mixing it dry it's a horrible mess, and if wearing gloves, you WILL get them stuck in the ball of splash zone.  It will remain usable for a good little while in the water but will eventually set up.

Drew, thanks for the tip, but do you have any problems with adhesion to a port when it's wet like that? I'd really like to make sure it doesn't release and get sucked into a chamber

Edit: After reading about it, I guess mixing with and under water isn't a problem. The "olive green" tint sounds like the stuff I've usually seen on intakes and heads. Thanks again for the tip!

[jayb]

Doug, one thing about epoxy in the ports is that the epoxy adheres better to itself than to the aluminum or cast iron.  So, make some mechanical points where the epoxy can't get out when you do this.  For example, when doing the ports on a head, cut a thumbprint or groove out of the manifold mating surface into the port, and then when you put the epoxy into the port, fill in the groove also.  File it flush with the mating surface of the head, and then when the manifold is bolted into position that part of the epoxy is sandwiched between the head and the manifold, and can't come out.  So, if the epoxy starts to come loose from the aluminum or cast iron, you will have a mechanical hold to keep it in place.  Blair P gave me that particular bit of wisdom, and I think it makes a whole bunch of sense...

[Drew Pojedinec]

Only time we've ever had the stuff come loose is because of improper prep to the area or with steel that rusts enough so the epoxy flakes off.
For steel we do the, wire wheel/scuff it up, Ospho, clean with thinner or carb cleaner and apply kinda method.  Aluminum we just make sure it's scuffed up and go from there.

Fun fact for all.... in the maritime industry if you ask for Zspar, no one would know what you wanted.  If you asked for "splash zone" the engineer would know what you mean but probably no one else, maybe a savy Captain.  If you asked for "monkey shit" you'd be immediately taken to the locker with two rusted old cans, part A and part B.
We get bored and make sculptures outta the old stuff when we get really bored.  some guys are pretty darn good with it.

A recent sculpture spotted on a tugboat... was titled "Capt Dicktater abuses a bowl of chocolate"

[Barry_R]

I've had epoxy stay put for a really, really long time in an intake - probably ten years.  Before putting it down I beat up the surface with a rough burr in a die grinder just kinda "chattering & bouncing " on it.  A clean up spray rinse with the bad stuff chlorinated brake cleaner, a shot with the air hose to dry and on it goes.  I've seen some parts with a "stud" drilled and tapped in place as a retainer.

[cjshaker]

Thanks for the great tips, guys. The intake is aluminum, so making some points for adhesion shouldn't be difficult. In fact, a few places will have to transition to the head mating surface, so I may do that to all of them. Then I can have the mating surface milled flat. It's an interesting and cool intake, one I'm sure you guys will like, so I'll post some details soon.