edgarcia737

This motor reminds me of an ol' Mooney 231 I use to maintain, Tight!

My question is what tool does one recommend to remove the allen head nuts that attach the heat exchanger to the cylinder head? And where does one purchase such a tool?

Thanks again,
Ed

edgarcia737

nevermind

Diamond Blue

Use heat as in "cherry red" then they will come off without too much problem. Easy to break exhaust studs unless someone has had it off before and used anti-seize. It is a major PITA if they break.

Ed Hughes

Diamond Blue's point is imperative to heed. You need a real torch or you will be stressing out on how to fix the broken stud that will result otherwise.

edgarcia737

Thanks guys, off to my dad's to get my oxy acetylene torch back.

sig_a

You may want to try Kroil or PB Blaster before heat. Mine came off without any heat and a good and long soaking of PB Blaster.

Ed Hughes

If I were to do this with any car going forward, I'd not even waste time with the chemicals. I've seen too many examples of them being 100% ineffective, that it isn't worth the optimism or the three days of crawling around under the car to spray the nuts in preparation. Then, on the day of reckoning, the odds are you find they won't budge and need the torch anyway, and now you've got to burn all of the goop off from the spraying.

Of course, some respond to PB, but those have to be in the minority, especially if the HE's have never been off.

theiceman

I agree with ED .. I f they are on that tight it is hard to believe the chemical can penetrate more than a mm max.

Mine scare the crap out of me and they will just about rust off before I atempt to change them.

Ed Hughes

When I put my headers on, I did the PB thing for a few days. Got the very first nut loose-so I thought-THEN the stud broke with about 10 or 12mm showing past the flange. That woke me up and made me realize how lucky I was on that one. I used oxy-acet from then on, and got all of them off without incident. Luckily the stud was still long enough to work, and eventually was replaced when I rebuilt the engine.

The problem with breaking studs is that it is not a fun issue dealing with the results. Yes, there are drill jigs and I've heard of portable EDM rigs, but to me, it isn't worth the liability of damaging a hole.

Ed sounds like he has the proper tools. I always love an excuse to fire up the torch.

NOTE on this process: I found it best to get the nuts cherry red, then slightly try to tighten the nut (I could feel them move a hair), and then immediately go to loosening. Worked like a charm 11 times for me.

rusnak

put that one in the solution file.......

Diamond Blue

+1 with Ed. I tried Kroil and got 1 off. Not worth the chance of breaking a stud. Got the Oxy/ acetylene torch out and got the nuts cherry red. They turned right off but not without screaming the whole way off. Hard to explain the sound, almost like nails on a chalk board. I put copper anti-seize on when putting them back on. Was planning on going to 993 heat exchangers at some point in the future. But heat will be used if there is any resistance removing the nuts.

originalmotorhead

So what about the allen bolts? Do you heat the **** out of those too or do you heat the head?

Tom

Diamond Blue

Heat the allen bolts the same way. It is a major PITA to drill a broken stud.

rusnak

Will Mapp gas get hot enough to work? I know that Orchard Supply has some nice small torches that will get in above the heat exchanger really well. That's where I got mine, which I used on my oil lines, and also to burn off my stock suspension bushings.

Ed Hughes

It may get hot enough, but you'll go through too many bottles of the stuff.

They are allen headed nuts, otherwise called barrel nuts. they get nice and red, you want the heat on the nuts.