'73 Ls4 A.i.r

[Peter G.]

I have just found all the correct A.I.R. System parts for putting back on my '73 454 engine. It looks like a pretty simple job with the exception of removing the "rusted" plugs from the exhaust manifolds. This engine probably hasn't had an A.I.R. on it in many decades!

Has anyone done this job before and if so can you suggest what will work to remove the plugs on the exhaust manifolds.

I have heard a liquid wrench lubricate, wax and even heating the manifolds?

Need your help, please.

Thanks in advance.

[Joe L.]

Re: '73 Ls4 A.i.r

I have just found all the correct A.I.R. System parts for putting back on my '73 454 engine. It looks like a pretty simple job with the exception of removing the "rusted" plugs from the exhaust manifolds. This engine probably hasn't had an A.I.R. on it in many decades!

Has anyone done this job before and if so can you suggest what will work to remove the plugs on the exhaust manifolds.

I have heard a liquid wrench lubricate, wax and even heating to manifolds?

Need your help, please.

Thanks in advance.

Peter----


I can tell you that it's a bear of a job to get these out. I think you're going to find that any sort of "penetrating oil" is going to be virtually useless. I haven't tried the candle wax trick, but I really don't think it will work, either.

If the plugs are steel, external HEX HEAD plugs, you may be able to get them out by using a high torque impact gun. I'd give them several soakings with "penetrating oil" first, though. As I mentioned, I don't think this does much good but it may give you a slight advantage. I have removed external hex head steel plugs in manifolds using this method.

If the plugs are external square head, you'll likely twist the heads off using the impact gun method. Internal hex or internal square head will "round off" and you'll get nowhere.

I really think the best and most reliable method is to heat the area surrounding the plugs as hot as you can with a MAPP or acetylene torch. Then, quickly turn out the plugs while the manifold is still hot.