[craigs69]

The Resbond showed up in my UPS deliveries today, so I am planning to do the fill this Saturday when I have time to babysit it as it sets.

I have the aluminum all removed now. It took a little over 6 hours of drilling & grinding to get it out, but all went well. It looks like it will be a pretty easy fill through the valve seats. Just a bit more sanitizing of the interior of the crossovers so I can get a good bond and I should be ready.

[72LuxuryLeMansLa.]

Originally Posted by PunchT37

Mine did that. Could hear the noise too. I ran 2 small screws on 2 sides between the slug and the port. Little self tapping screws. They sit between the slug and the port wall. They cut into the slug and half the dia. of the screw pushes against the port wall. They push the slug inwards and hold it tight. Take a chisel and break the screw heads off flush. Been like that for years now.

Wade,

Did both sides come loose? Just one head?

[PunchT37]

Originally Posted by 72LuxuryLeMansLa.

Wade,

Did both sides come loose? Just one head?

It`s been a while but, I remember only one head did that.

[ron thorne]

Steve25: Any particular brand of hydraulic cement?

[craigs69]

After about 8 hours of grinding/sanding/cleaning, I finally did the Resbond pour today. It went remarkably easy and nearly mess free. The instructions for the Resbond state to mix 100 parts powder to 30 parts activator. I initially mixed 200 grams of powder and 60 grams of activator, which turned out to be the perfect amount for one port, but it was a little bit thick and wouldn't pour. I added another 5 grams of activator and it thinned to the perfect consistency to flow through a small funnel in the valve opening.

It has been about 4 hours since the pour and the Resbond is starting to set. I can see that it has settled a bit, but not enough to make a difference. My plan is to let it cure for a few days and then send it through a secondary cure in the shop oven at 250 degrees for a few hours. With the way it layed in the ports, I really wont have much, if any, shaping to do in the fill area.

[69Farburd]

I'm glad it worked out well for you. I was happy with it when I used it on mine.

[Sscott]

Has anyone tried using the respond on top of the aluminum?
My aluminum fill iss very uneven and has valleys near the outer edges. Respond says it bond great to metals. Can I just add that stuff on top to get a even coat?

[lust4speed]

Old thread given new life.

I think a thin skim coat wouldn't last. If you ground out about 3/8" of aluminum I'm sure the Resbond would be a permanent leak free repair. Back before we started using Resbond we would heat the head in the barbeque until we had the heads between 400-450 degrees before making the pour, and then simply shut the lid after the pour and let everything slowly return to room temperature. The trick with either aluminum or Resbond is to have enough material ready to pour so you don't have to stop the pour and get more material ready. Cold joints are not good. We also found that old window and screen frames was the easiest to work with since they were a good quality of pure aluminum. The pistons were the worse taking much more heat and having much more slag. We would also do the pour prior to any work on the head but after cleaning and magnafluxing just in case the pour induced any warping.

Aluminum pours were always stressful, and there was no second chance on the pours. After the first time using Resbond we never went back to pouring aluminum. Resbond is like working with pancake batter and you can form the valve bowl over an hour after the pour and gently work it into a perfect fit. Not too bad doing the final shaping with a die grinder. The aluminum needs an overfill so you don't end up with a depression and the removing the excess is time consuming where the Resbond can be played with until it finally hardens - but by that time you have shaped the perfect bowl. Just don't pour and not check on it because just like batter it will continue to ooze and droop for quite awhile.

I made the mistake of using a nice square of 1/4" plate glass to mix the Resbond on thinking it could be popped off after drying. It completely bonded to the clean glass and no amount of convincing with a razor blade removed it. I'm sure that it bonds even better to porous cast iron.

Using the barbeque leaves the finished heads with a pleasant hotdog and hamburger order but it goes away pretty quick. Last pic is the Resbond fill.

[shaker455]

Originally Posted by 69Farburd

I did Resbond in my heat crossover several years ago, I put some kind of putty (like silly putty) in the valve ports and poured the Resbond through the exhaust ports. I did not heat treat the Resbond, but let it sit for a few days. It has held up fine so far.

X2 Resbond by Cotronics, It's a ceramic epoxy mixed by weight.
You can use that to seal up the gap and it will withstand any heat.
I've used it in the past a few times to completely fill exhaust crossovers.