Stuck AT cooler hoses - PeachParts Mercedes-Benz Forum

JHZR2 · #1 12-03-2003, 10:36 AM

Hi,

The AT cooler hoses are completely seized on at the radiator end. It looks like there are metal threads that are somehow part of the radiator bottom (which is an original BEHR and is plastic). The hose couplings are seized onto these threaded attachments.

I have sprayed them liberally with penetrating oil, tapped the joints quite a bit to make some vibration to loosen stuff, driven the car so it gets temperature variations, all with no luck.

I dont want to break the plastic on the radiator, or ruin the metal connection that the hose screws onto...

Any suggestions?
Thanks,

JMH

lrg · #2 12-03-2003, 12:30 PM

You might try a little bit of heat with a propane torch. Although the radiator is plastic it is a radiator after all and it should be able to take a reasonable amount of heat as long as you're careful. Don't focus the flame on the radiator itself but rather heat just the coupling. It might also help if you use a flare wrench if one's available. If that doesn't work and you really need to replace the hoses you have no choice other than to risk breaking the radiator.

MikeTangas · #3 12-03-2003, 12:34 PM

If I remeber correctly I believe you need a backer wrench on the fitting to the radiator. I could be wrong though.

JHZR2 · #4 12-03-2003, 01:52 PM

What is a Backer wrench???

Looks to me thatit would work fine with my 19mm wrench, if I wasnt worried about torquing it too much and breaking stuff...

JMH

lrg · #5 12-03-2003, 02:22 PM

I think Mike means use a second wrench to hold the nipple that comes out of the radiator. I don't recall if there is a hex end on it or not. If there is the idea is to use the second wrench to take the torque rather than the radiator body itself.

A flare wrench will distribute the pressure slightly more evenly than a standard open ended wrench. They are very useful when trying to remove hoses with soft brass couplings.

JHZR2 · #6 12-03-2003, 02:42 PM

AHA, there was a large hex shaped part on the nipple coming from the radiator. It was too big for my wrenches (I have 19mm largest), but Im sure a pair of channel pliers, or my big adjustable should work well... Ill keep penetrating it with oil or a while, then go at it in maybe a week, with thta method. If it doesnt come off then, I guess Ill leave it, and when they look real bad, go at it, fully prepared to buy a new radiator (maybe have a shop do it justin case...).

Thanks,

JMH

MikeTangas · #7 12-03-2003, 07:41 PM

IRG is correct in what I meant by a backer. I can't recall off the top of my head, but I think it might be 21mm. You have to hold that fitting. If you don't have a suitably sized metric, you could use an SAE sized wrench because once you start getting nearer to the 25mm sizes metric and SAE start to match up. Just be careful and get as close a fit as possible (or go out and buy some larger metrics).

I would also suggest locating some PB Blaster and use that rather than Liquid Wrench, WD-40 or oil. PB Blaster works miracles.

JHZR2 · #8 12-18-2003, 05:11 PM

OK, I have to bring this one back from the dead...

I have an appointment to have my car's trans done tomorrow am, first thing.
I really wanted to get the cooler lines relaced before then, but I am having no luck at all...

I have used all the typical things, heat, tapping, vibrating, tightening, etc., and they just do not budge either way. I cannot get movement no matter what.

I have been using pblaster for a while amongst all this stuff (Its smoking vapors are not good), with no luck, the coupling is just plain stuck to the fitting on the radiator.

I really want to do these lines, but I dont trust the dealer, they stripped the oil cooler lines and I ended up buying a new one of those, and I DO NOT have the money for a radiator from the dealer, Im sure itll be $1000 when all is said and done.

Any other help? They do not weep, but they do have cracks in them, and it would be really great to be able to replace them.
Thanks,

JMH

rs899 · #9 12-18-2003, 05:32 PM

You might consider cutting the hoses as close to the radiator as possible and then you may be able to use a deep metric socket over the stump with the "backer" wrench on the radiator flange. Or use a box wrench over the "stump" and position it and the backer wrench so that you squeeze them together so as not to stress the tank. If that doesn't work (and at that point you are semi-screwed anyway), you can remove the radiator and work on it at the comfort of your bench. You MAY be able to cut the fittings across the threads and spread them similar to what they should have done on your oil cooler! These are just thoughts. I have not had this sort of problem on the radiator.

Rick

JHZR2 · #10 12-18-2003, 05:36 PM

I think my problem is that this is the original radiator and original coler lines. 20 years of salty roads does its part... Why they didnt install them with anti-seize (or the oil cooler lines for that matter) is beyond me...

JMH

pberku · #11 12-18-2003, 06:24 PM

If you have, (or can borrow/buy) a Dremmel tool with cutting wheels, you can then cut through the stuck bolt, and remove the dumb thing without harming the radiator.

Make sure you have a Dremmel that is 30,000 RPM capable.

Phil

dieseldiehard · #12 12-18-2003, 07:10 PM

Aren't they all 30K RPM? I just posted on a thread re: Turbo replacement, that I have split bolts using a Dremel. I would add that one should use a full face shield. Those cut off wheels are real thin, if (and when) they break they go all over the place. This technique has been pressed into service on things like Wheel nuts (non. MB) and rusty exhaust manifold nuts with good results.
To do this, one cuts a notch along the axis of the nut, then you can stick a screwdriver blade in the gap and open the nut to a looser fit if necessary.

Dieseldiehard
1971 220 (gas) 4-spd manual 104041
1979 300TD w/ ’85 turbo engine 289560
1983 300D 237490
1985 300TD 206150
1975 300D (looking for an engine)

pberku · #13 12-18-2003, 08:38 PM

Not all Dremel's, at least here in Canada, are 30K RPMs. Some of their lower-end, and rechargeable models go up to 15-20K RPM only.

I do agree with Dieseldiehard's, comment of the cut-off wheels potentially flying all over the place when they break.

cwa · #14 12-19-2003, 10:28 AM

Replacing the AT cooler lines was one of the first things I had to do with my latest purchase. I expected something like this but they both just came off very easy.

I really like the full engine and tranny cover under a w124 as it keeps the salt deposits from building up.

bodyart27 · #15 12-19-2003, 11:19 AM

Here are some pics of mine:

http://www.peachparts.com/shopforum/showthread.php?threadid=79278

Anyway, what I found was to get some nice leverage, I took the fan shroud off and the fan in front of the radiator (as seen in the pics). That gave me some nice leverage to loosen and tighten the AT line from the top or bottom.