Cleaning Heat Exchangers need a chemist

[guards73/2.0]

I've been reassembling and can't bear to put
my stainless steel heat exchangers on when
the rest of my motor is detailed. I's not
Concours D'Elegance material, but I have a
buddy who's done that with a Dodge Challenger
and after a visit to his shop the idea of bolting these things on with cooked-on oil gristle
bothers me. I'e like to get them cleaned up like new first.
I've tried:
Degreasers
Carb Cleaners
Oven Cleaner
SOS
Red auto body Scotchbrite pad/cleanser
Alloy Wheel etching acid
...and I'd like to believe that I could get these things clean without spending all day at it. Getting the main expanse of metal clean was easy, I'ts just the areas around the
welds that's so tough to get the gristle to leave hold of the Stainless Steel.
Any ideas/experience with this? I was thinking of bead blasting them.

[David McLaughlin]

I used Simple Green and a steel brush with pretty good success. It too two rounds per exchanger and came out looking pretty good. I just wish I had them powder coated while I had them off.

Good luck


------------------
Dave
1970 914/6
1995 Golf GTI-VR6
1996 Passat TDI

[bowlsby]

I don't think powder coating heat exchanegrs would be the right thing...especially for stainless steel.

Leave stainless...stainless. Its beautiful.

If they were plain steel, then how about ceramic coating them?

Powder coating is not a cure-all finish. It is a relatively thick coating applied with heat (not sure if its a thermoset or thermoplastic). But I would not put it on anything that gets as hot as heat exchangers.

[914Hugh]

I used the steel brush as well. I would add though that I used a chisel where the muck was particularly thick before going to the brush.

I also used a steel wire brush to get the crud off. I carried the exchangers to a wash it yourself shop (with hot water psi washers). I soaked the heat exchangers in Gunk engine degreaser, wire brushed them and then psi washed 'em. I did this 2 or 3 times in a row and then hit the really hard parts with steel wool once I got them back to the house.

Good luck!

[mike mueller]

Castrol Superclean, sold at Wal-Mart and other stores or you can sandblast them.....I did my exchangers and they look nice, they will look even better when I apply the aluminum/ceramic coating to them. This is perfect for the DIY guys out there.

http://www.techlinecoatings.com/Exhaust.htm



------------------
Mike Mueller
Antioch, CA
'75 914 2.0
http://www.pelicanparts.com/MotorCity/mmueller/personal.html

[Jake Raby]

I USE A TORCH!! The main idea is to get the inside free of old oil and dirt, else a horrendous smell will engulf the car, nothing works on old oil and grease better than heat...Combine it with degreaser or 2 and you should be good.

------------------
Jake Raby
Raby's Aircooled Technology
www.aircooledtechnology.com

[guards73/2.0]

Degreaser is primarily diesel fuel I think. Not gonna get near that with a torch! I already did the degreaser thing at the car wash to get what I could out out of the insides by just flushing. Hopefully I'll get the chance to burn off the rest by turning on the heat driving with the top down on cool days. ( It's HOT up here in MN this week, we sadly lost one of our Vikings to heatstroke the other day). Thanks, but this torch deal sounds like a very dangerous method to me. I had them bead blasted, they look great now ( after finishing with red pad). Thanks all

Originally posted by Jake Raby:
I USE A TORCH!! The main idea is to get the inside free of old oil and dirt, else a horrendous smell will engulf the car, nothing works on old oil and grease better than heat...Combine it with degreaser or 2 and you should be good.

[Scott S]

My 72 came with SS heat exchangers, but they were not maintained to my anal standards. Over a summer of washing and detailing they look new, and after 5 years they still do. I used good old fashioned "Gunk", a wire brush and then two grades of steel wool. Since then I have been using a 3m industrial ss cleaner that I got from my former job (Volant Skis). It spays on like bathroom cleaner (foam) and just wipes off. Since the initial "summer of cleaning" that is all I have had to use to keep them looking new. I am not sure if it is available over the counter or not.
-s

[ovilla]

I went to Sears and got two round wire brush attachments (one small and one large) for my drill. Then I sprayed the heat exchangers with WD40 and PB Blaster and went at it with the drill. This will trully make your heat exchangers shine like brand new sheet metal. Then as a finishing touch dry off the heat exhangers and brush them in only one direction from tip to tip. I brushed them going across (as in from side to side, not front to back). To clean the insides, buy an old toilet cleaning brush (the metal one), and cut the end off and then chuck it into your drill. You should be able to reach pretty far into your heat exchangers.

[Jake Raby]

The torch method works well, even if you have previously degreased them, the heat gets alot of the crap out that will stink you out of the car, no degreaser gets rid of it like the heat..

I have done it atleast 100 times, and I'm still here to tell about it..