Removing heat exchangers

Its been like what? 10 maybe 11 hours since I have asked a question. SO I decided to keep you Porsche gurus (ya you!) on your toes.

I finally rigged someting up so that the ol' 911 engine is on the stand and i'm trying to figure out how the hell i'm going to get the heat exchangers off. I'm debating just cutting the bastards off but I'll wait for someone to tell me thats okay :P . I don't plan on keeping the exchangers but the money from their sale would come in handy. So fellas, whats the trick?

As usual, I appreciate your plethora of comments and bottomless pit of P-Car information.

The ever-inquiring,
Adam Roseneck

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atr911@hotmail.com

Adam,

If you do a search of the Pelican archives on 'heat exchanger nuts' ... you will find a half-dozen or so past threads on the subject. Be sure to read them all ... before starting the project!
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Warren Hall
1973 911S Targa

[This message has been edited by Early_S_Man (edited 02-08-2001).]

Thanks Warren, I didn't know that you could do a search on here. You learn something new every day.

Unfortunatly, me, being my over zealous and impatient self, tried to start working on the heat exchangers. So far, I pulled one stud out, snapped one stud off (not sure how bad yet) and got one off clean.

The engine is comming apart an I may be changing the cylinders, so i'm not overly concerned about snapping the studs however I would like to avoid any possible problems so i'm going with teh torch. (I have a small butane torch, think this will be okay?)

Thanks for the info,

Adam Roseneck

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atr911@hotmail.com

ADAM, PATIENCE.I SOAKED MY STUDS WITH WD-40 AND REPEATED THE SOAKING FOR THREE DAYS.TWO STUDS BACKED OUT BUT NO BREAKS.THREADS I'VE SEEN IN THE PAST ALSO SAY HEAT CAN BE A TRADE OFF FOR TIME.BUY THE WAY,EVEN IF YOU REPLACE THE P&C'S YOUR STILL GOING TO NEED TO ADDRESS THE BUSTED STUDS,THEY'R IN THE HEADS. HANK

Yikes! For the best penetrating/rust penetrant -- get some 'PB Blaster', NAPA or other automotive stores. This stuff is way better then anything else I have tried. Then, after three day soak, there is still a high probability of snapped studs. Heat helps, but still no certainty. Then, if all has failed and the stud is snapped off flush with the head -- take the afflicted head to a machine shop equipped to remove it. Don't even think about an 'easy out'. Search on Rennlist for much information on this.

I don't know how effective that butane torch will be. I know that Warren has suggested an Oxy/Acet. "rosebud" for this purpose.

Background on this: I used to use a Smiths torch with a range of #3 (smaller) to #7 (larger) tips for brazing work on bicycle framesets. The rosebud we used was a screw on multi-holed tip that could heat an area up to 6" round very quickly; this was commonly used to braze tandem bottom bracket shells to the .035 moly we used for the bottom tube.

So now I am wondering if the suggestion of using a relatively "broad" heating tip (i.e. rosebud) is better that using a smaller tip that might concentrate the heat in a smaller area, thus possibly deforming the 'head? This is something you might factor into your decision; hopefully Warren will comment on this.

Anyway, point is that you will need a bigger heating device than the butane, and I would suggest renting an oxy/acet setup short of getting a friend over with this equipment in hand. This only if you are 100% determined to get those nuts off. Otherwise, I'd soak, turn in first, then turn out.

One thing I've found in removing stuck nuts etc. is that minute turning of the frozen nut/bolt with total saturation of penetrating fluid frees them up. A little in, a little out, fluid; off to next nut for same; return finally to first nut, a little nudge; back around the horn---you get the picture.

Good luck; we are all rooting for you!
Jw

Patience is such a virtue. My favorite penetrant is called Maltby's Penetrating Oil, found in most Diesel parts shops. Use mass quantities of penetrant for days before removing the fasteners.

Heat works best. Butane and propane are not hot enough. Oxy/Acetylene is hot enough. Some guys really knwo how to use those things. Muffler shop guys do.

Patience. And if a stud breaks off, a machine shop can remove it safely.

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'83 SC

WD-40 is just what its name says it is: Water Displacement agent, formula #40. It was not made to act as a lubricant.

Try using a real penetrating oil, over several days, and if this does not help, then like Warren suggested, heat.

JoeA

I hate to beat a dead horse but,,,,, Follow Warren's advice in previous threads. I soaked the studs for 1 week straight ( sprayed some pen. oil every day), then map gas torch on each nut until red,,, let cool,,, heat again. Tighten slightly then loosen. 2 backed out and all others came off fine. I'm not running the sweet setup with lots of VVVRRRROOOMMM!!
I tip my hat to you and your experience warren.

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85 Carrera Targa

Adam. Patience. And heat, like Warren said. Just did mine. Couldn't get MAPP hot enough by itself. Never got to "rosebud".
Make sure you get at least a little additional "in" twist before you start backing them out. I broke one only because I wasn't patient.

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Cary Kutter
77 Carrera w/3.2
Rennlist #001117-2266
PCA Region - Big Sky

My favorite penatrating oil is coors light, nice and cold. Then I reach into my tool box and bring out my nut splitter. (OUCH!! sounds kinda bad) and just split the nuts off. no mess no fuss....and for $20.00 it has been a life saver.

Tim in Sac
'77 911s