Ever had Z spar A-788 give you trouble?

[CFM-Z440]

Hopefully this hasn't been beat to death. I'm looking for some advice on using epoxy in intake ports. I've been using Z spar A-788 splash zone expoxy.

My first question is can it survive bare in an intake port. I've read that it does as long as you don't run alcohol, and I've even got a couple out racing this season with it in them, but on two different batches here in front of me, if I dab gas on a rag and rub it (not hard) It seems like I start wearing into it. I would tend to think it'd get washed away. I've got two heads that are waiting to be sent out right now because I'm concerned about this. Stranger yet, One set up very hard, and the other stayed soft enough I can scratch it with my thumb nail. When I put the stuff in the port, I was thinning it with water to make it manageable. Is that a problem?

It seems like at very least, I should seal over it with something. What can I use and where can I get it quickly? What experience do you have with this stuff? Any tips? If any of this doesn't make sense, I've been up for 22 hours and I will fix it later

[BlitzA64]

I have seen it written that some use clear Imron to coat it. I used some of the MOROSO 2 part putty on some heads in the 80's and it held up ok even in an alky environment. It was staked very well but then again maybe I got lucky. I think prep is 99% of the battle with any of this stuff.....

[SMITHBERGRACING]

I've used lots of it and never have had any issues. Surface prep is VERY important! I've also have heard of using a good automotive clear coat to seal the epoxy for use with alcohol. Also make sure you mix the epoxy well and use 50/50 mix. It tends to go soft if you don't use enough hardener (black tub).

[CFM-Z440]

Maybe my first issue is that I should measure the parts new equally than "yep, that looks even" Clearly my eyes can't measure volume as well as I thought. I think I'm good on surface prep. I dig a trench in the port where the edge will be to keep the edges thick. I also cut a bunch of slots for the epoxy to grip to. Then I rough the surface with 60 grit and clean the metal with alcohol.

The stuff is super sticky, thick, and just plain hard to work with, so I thin it with water. I mix it uniformly, then apply it by rolling it into the grooves with a screw driver. When I have enough in there, I wet my finger, and dab it into shape. (That's what she said lol)

Any problems with that?


To seal it, a good friend of mine suggested Wurth Rust Guard, Black. 12oz is over $50. I'm hoping maybe I can find something cheaper?

[SMITHBERGRACING]

I also dab my finger in some water to smooth it out. I believe it was designed to repair boat hulls so water shouldn't be an issue. I have tried using lacquer thinner with similar results. I usually just use a aluminum porting burr for a finish where possible to rough up the material

Not sure on the paint, haven't tried something like that yet.

[Walter R. Malik]

I seal it with "Fuel Proof paint" from the model airplane store.

[BlitzA64]

I seal it with "Fuel Proof paint" from the model airplane store.

Great idea!

[Keith Morganstein]

When I put the stuff in the port, I was thinning it with water to make it manageable. Is that a problem?

How were you thinning it with water?

[CFM-Z440]

When I put the stuff in the port, I was thinning it with water to make it manageable. Is that a problem?

How were you thinning it with water?

A few drops of water seems to transform the stuff, and makes it much more agreeable to work with. It seems really pasty and sticks to everything it touches without a little water.


Before applying it, I drip some water on it, and mix it in. If I dont, it's hard to get it to stay in the port. It sticks to the screw driver and tries to come back out with it. The same goes for shaping it with your finger. If you wet your finger first, it stays how you form it. No water, and it's a disaster.

[CFM-Z440]

I seal it with "Fuel Proof paint" from the model airplane store.

That might be exactly what I need, and I think I can get it locally... Thanks!

[SMITHBERGRACING]

I don't mix water in mine just dab my finger in the water to smooth it over. I want the epoxy to be sticky and bond to the metal. Water mixed in probably does the opposite.......

[rookie]

The water should not be a problem.
http://www.go2marine.com/product/79357F ... a-788.html
Splash Zone Compound, A-788. With near magical properties, Splash Zone epoxy fits the needs of boaters, marinas, coastal home owners and race engine builders! It can be mixed and applied underwater and will cure underwater as well as in the air. This product is great for racing vehicles since it also stands up to heat, vibration and fuel on port intake manifolds.

Can be mixed and applied underwater and will cure underwater as well as in the air
Adheres to any clean sound surface, either wet or dry, including aluminum, galvanized steel, steel, concrete, wood, fiberglass and existing coatings
Cures to an extremely hard coating which is abrasion and impact resistant
When mixed properly color turns to olive green

[airflowdevelop]

A few things to check on.

1. How old is the product? if older then 1 year since opened toss it. If you want to preserve it even longer fill the cans w/ argon before you seal them up.

2. You can certainly use water to mix and apply...no issue at all. You can even use a quality lacquer thinner if you wish.

3. DO NOT USE ALCOHOL TO CLEAN THE PARENT MATERIAL! Acetone or lacquer thinner only!

4. Mix EQUAL amounts...and by mix...I mean mix the living snot out of it.

5. heat is your friend. Never try to mix it below 65 degrees and let it set for a while even at that temp... and remix a few times before applying it.

6. Watch using todays Imron as a top coat as the solids count is way down compared to before. Devcon 2 ton clear or U.S.P Bond clear works perfect w/ alcohol.

[CFM-Z440]

Awesome, thanks guys! The stuff is coming up on a year old this spring. I can certainly blow argon at it when I seal it back up though. Is there a way to tell when it's past it's prime?

Also, noted about the alcohol. I will get some acetone. I don't really know why I got alcohol anyways other than ease of access. For what it's worth, I did dry it completely before applying the epoxy.

The port that seems soft has probably not seen more than 60 degrees, even when it was applied. I don't know if that may be the issue or not there. I have a feeling I just was off on my mix ratio. I can't tell any difference in color, and I did mix the stuff till I couldn't stand it anymore.

[Greens Nice]

Has anyone tried the red paint used to insulate armature's in alternator's?
it seems to work fine painted on the inside of an engine that see's methanol in the sump, but will it work on an intake port?