Wax on the exhaust manifold

[Inf]

Well if you're reading this after seeing the title I guess you either have done this or you're looking for a good laugh at my expense, or maybe both!

I pulled the air gallery out of my exhaust manifold several weeks ago and used the 'wax and propane torch' method some have written about to losen up the fittings(this is on the bench mind you, NOT with the manifold on the head). Unfortunately I couldnt get all the wax off the outside of the manifold :disappoin , the roughness of the casting just let it grab on like im sure you can imagine. I figured i would just let it melt or burn off when i ran the motor.

Fast forward to tonight, I finally cranked the motor after a long project (for me that is) and it fired up and ran, running pretty rough though since the carbs are all out of whack. will tune them tomorrow. After a few minutes the engine started to warm up, and i started noticing smoke coming from the engine compartment! :paranoid:

I shut the motor off and went and looked, it was the wax burning off the hot exhaust manifold :stupid: . There's a lot of it, and it smells terrible : like the smell when a cheap candle smolders after you blow it out. Anyone have any clue about some sort of chemical, acetone or something like that to get the stuff off without having to burn it off? Pulling the heat shield and wiping down the manifold would be worth my time if I could avoid having all this candlewax smoke come off at me! If need be, i guess i'll just deal with it and let it burn itself off.

Once I get the motor dialed in I need to sort out some electrical gremlins. My parking light control in the combination switch is shot (corrosion + heat damage due to resistance from corrosion), I tried resoldering the connections but its a no-go once I put everything back together. I think I might just macgyver in a radio shack rocker switch for now so that I can pass inspection. Can't really afford a new combo switch. Anyone have a spare laying around? VB's $169 is a little much for me after spending hundreds already on more important parts

[Bambikiller240]

Andrew: I've never heard of the "wax and propane torch method". Could you direct me to info on it, or post what you know?

If you are willing to take the manifold off, you could have it hot tanked at a radiator or machine shop. Just a thought.

Also, what did you use to plug the holes where the Air Galley was connected previously? IF you used plugs, can you tell us the exact size, & thread information on the plugs that you used.

Thanks for any information you can provide on either of these matters.

Carl

[Inf]

I think I read some posts about it here, but I mainly remember people talking about it on zcar.com in the archives.

Basically what they were saying was that when using heat to loosen up a fitting you melt some wax over it because the molten wax will penetrate the thread and wont evaporate like penetrating oil would. It worked alright, but it left me with lots of wax stuck to the casting. I wouldn't recommend it for this particular situation.

I think the original air galley fittings are BSPP, I searched around and couldnt find any BSP fittings locally. I'm not sure what size plug you would need in BSPT, I ended up using some 1/8" brass NPT plugs (i think 1/8", could have been 1/4" though since I bought a bunch of each for plugging some other holes up, it was whatever hole is closer to the injector fitting size). I decided to do this after seeing some posts on zcar.com from regulars saying this worked out fine. It didnt actually seal up like it would have if the hole was in NPT, it actually went in sort of snug(probably due to thread interference), but all the way in nonetheless. I put plenty of permatex high temp anti-seize on. I figure if I have a leak there I can order some bspt fittings and swap it out without pulling the manifold from the car later.

I thought about retapping the hole for an NPT plug, but after tapping the holes on the balance tube (soft aluminum) I figured tapping that cast iron by hand would leave me with a broken tap in the hole. Tapered taps start putting out a whole lot of resistance when you start to cut really far in.

I called a bunch of places in the yellow pages (plumbing and hydraulic companies) and not one place had any clue what I was talking about when I asked about british standard pipe fittings. Apparently parker makes them, but they need to be ordered through some distributor for hydraulic parts.

I think the biggest exhaust flow bonus by yanking this stuff altogether would be getting rid of the pipes that go into the exhaust ports. Seems like they would disturb the airflow a lot. Once you pull the fitting on the outside out, you should be able to knock the injector pipe out with a rubber mallet or something. (hitting it towards the manifold). Some of mine were pretty well rusted in there and took a lot of pounding, twisting with vise grips, and cursing to get them free.

[Bambikiller240]

...........I think the biggest exhaust flow bonus by yanking this stuff altogether would be getting rid of the pipes that go into the exhaust ports. Seems like they would disturb the airflow a lot. Once you pull the fitting on the outside out, you should be able to knock the injector pipe out with a rubber mallet or something. (hitting it towards the manifold). Some of mine were pretty well rusted in there and took a lot of pounding, twisting with vise grips, and cursing to get them free.

Right. Back in the day, this was a common modification. You pulled the galley to get at the pipes, and marked them so you could then cut them short so they didn't extend further than flush to the inside surface of the manifold.

I found a hardware store locally that has BSPT plugs, but I could not find one that would fit. Maybe they didn'nt carry the full line of sizes, but it looked pretty complete to me. Very frustrating.