I am trying to remove heat exchangers and first they are a little hard to get to the nuts holding them on and second the studs that the heat exchangers attach to seem to have shifted so that the flat side of a few nuts are but up against the exchanger itself .

is this common ?.. I am kinda hesitant to start prying on them too much before i find out if there is any other suggestions on getting them off

I really feel for you! What a b..ch job! Over the years they get bumped, new studs are put in crooked and "mechanics" use 13mm nuts instead of the prescribed 12mm headed copper locking variety. The only thing to do is to use a narrow wall snap on socket and tap it on hoping it will straighten the stud and nut so you can remove it. Make sure first however that you remove the muffler and anything else attached to the heat exchanger so you can manipulate it for the ultimate clearance. Soak those nuts!!!!! You do not want to break a stud!!!!!

The original nuts were 13mm wrench size, not 12mm. The original nuts for the 2 litre engines had a substantial flange, as well, and they weren't lock nuts. The commonly used 12mm wrench size nuts are NOT copper, they're copper plated steel. Porsche never used locking nuts on the exhaust systems of air cooled cars, IME. The Cap'n

I am sorry for the lack of clarification. You are correct. I was speaking about mechanics who have replaced the original factory nuts with built in washer with regular 13 headed 8mm nuts. WE prescribe the 12mm copper locking nut with built in washer. Makes the exchangers MUCH easier to remove the next time.

they are 13mm... and if I try and tap on the socket I am thinking it would dent the exchanger ... are they always a little hard to get a socket up to the nuts?

they are 13mm... and if I try and tap on the socket I am thinking it would dent the exchanger ... are they always a little hard to get a socket up to the nuts?
[/quote]

Yes. Tapping the socket on is frequently required, and little or no damage to the tubing will result from doing so. I generally use "wobble" extension so there's more flexibility in placement of the extension amidst the crowded conditions in there. The Cap'n

Hey Mike, when you're done, swing down to da sout' side and remove mine too. Then you can see how much you've improved!

well If I can successfully remove the heat exchangers, the engine , the transns and the damged trailing arm .. then reinstall them and set it all back so that it runs properly .. I will be there


oh yea by the way if you jack up the ass end of a 914 be sure that ALL the jack stands are solidly situated on the floor before you get under and start ynking on stuck bolts .......

yeah mine decided to shift to one side alnd fall on top of me ... I opted to stop working for the night after that

Use a 1/4" drive socket; they tend to have thinner walls than the 3/8" drive kind.

The originals I pulled off of my 2.0 had 13mm flats, and also slices in the side partway through; I believe that was how they deformed enough to "lock" onto the stud. The common aftermarket replacements use the 12mm flats (much easier to get a socket onto!) and are "squished" at the sides to provide the locking feature.

My recipe: Aero Kroyl (or PB Blaster), and tapping with a hammer and punch. Repeat every day for a week. My exchangers came off with no fuss. (Putting them back on was a different matter, they had gotten a little "tweaked" over the years.)

--DD

I wedged a big flat screwdriver in there to wedge it back apart far enough to get a thinwall socket on.....
Scary, but effective.

I have replaced the nuts on the heat exchangers with the 911 versions that use an internal allen head wrench. Much easier to remove later.

Just my $.02. Your mileage may vary.

--nice idea I like it does PP carry these ?