JB-Welding Upper Radiator Seam - anyone done this ? i have successfully used JB in the past to seal a cracked radiator (plastic part) on my '85 , when i couldnt afford a new radiator.....

this one started seeping after the second citric flush.....annoys me, i have to leave my cap loose now as well to not build pressure....

__________________
-Justin

I believe in extreme automotive perfection whenever possible.......there is no such thing as "It doesn't matter" !!!

1985 300 CDT - 287k miles

1980 240 D - 340k miles

With extras !!

http://facebook.com/BenzDieselTuner

http://facebook.com/SWFLAlternativeFuelsClub

http://facebook.com/SWFLBenzClub

http://SWFLBenzClub.com

Do it and don't look back. I've repaired more than one radiator with JB weld, the trick is proper prep-clean the surface with brake cleaner and/or ether, and be sure to put some nice scratches in the surface for the JB to stick to.

Let it sit for at least 48 hours before giving it pressure. An incandescent bulb shining on it may help it cure faster.

__________________
$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

Applying three layers of $100 bills also works very well. A tube of it is pricy though.

I wondering if the plastic cracks in one place from age and heat, there is the possibility of it doing in another spot?
I know when the finances are tight, we do what we have to do.

If it works and hold the pressure, good, I hope it does. I would be keeping my eye open in the yards for a new one. new one`s, or fairly new, do show up if you look for a while.

I tried to JB Weld a cracked plastic grill on my 240, and it didn`t stick very well. Different plastic, or I didn`t prepare the plastic good enough.


Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

How about using the plastic radiator repair kits that come with a piece of fiberglas cloth and a piece of sandpaper too, The liquids use to seal it get really scalding hot to melt the fiberglass and itself into the plastic.

__________________
2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

are you talking about JB'ing the plastic to the aluminum? I doubt that would work...

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

My local jy charges $35 for a radiator

__________________
1985 300D 198K sold
1982 300D 202K
1989 300E 125K
1992 940T

"If you dont have time to do it safely, you dont have time to do it"

"The democracy will cease to exist when you take away from those who are willing to work and give to those who would not."

I'm in the source a JY radiator camp. JB weld has its place (I use it a lot) but a plastic-aluminum joint with high temp deltas, I think is going to be a short term fix at best.

That being said, a tube is $5, and the radiator is bad anyway, so what's the harm? Silicone might be another option.

__________________
Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

As I read it, he just has a minor leak-not a big gaping hole, which JB weld would be perfect for sealing.

__________________
$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

I would first try AlumaSeal, which is powder you shake into the coolant. You need to put in the top hose, not the remote reservoir. It has worked for me on several cars to seal small coolant leaks, and it is more benign than the silicate solutions which can clog your radiator.

I wouldn't put any of that stuff in a car I planned on keeping. I have a feeling the heater core will be blocked in no time.

__________________
$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

I've used the AlumaSteel a lot over the years, also the small rubbery black ball sealant. Never had a problem with a heater core getting plugged.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Epoxy does work for a bit but may fail since it is less flexible than the plastic tanks.

Plastic tanks fail a few ways, Pressure cycles and degradation of plastic.

Everytime the cooling system builds pressure, the tank balloons out. The constant flexing eventually leads to a crack. Filling the crack stops the leak but does little to keep the tank from flexing. If you do make this type of repair, be sure to get epoxy in the crack and spread it around as an reinforcement. JB weld is more of a putty and seems to need help sticking to the surface.

Brass tanks aren't immune to flexing either.

When plastic degrades over time, epoxy only works in the very near term as there just isn't enough stuff left to glue to.

I have used JB Weld on radiator tanks with poor results, as in, it worked for a few months and fell off. I am with the "radiator sealant" group. I have Barrs Leaks in my 606 now. It has sealed a head gasket that was leaking water to the outside, for the last two years. I like this brand as I can mix it with removed coolant and allow it to settle for a few minutes before pouring about 3/4 of it back in. This allows the removal of the large particles that might plug anything important and would certainly settle out in the block. I have never plugged a heater core, that I know of. About 30 years ago some of the manufacturers of antifreeze sold a coolant with leak sealer in it as a value added. I'm guessing they stopped because brown sludge on the bottom of the jug was off putting to those who forgot to shake the jug.

__________________
'97 E 300 D

I have drug more than one BMW in off the interstate with cracked plastic cooling system parts that have been successfully repaired with JB Weld radiator repair material and sent on home. If you are in a bind then I say use it. Otherwise the most reliable, long term solution is to replace the radiator every say, 250k miles.

__________________
Jim

I once used a syringe (no needle of course) to inject epoxy into a radiator crack. This caused the epoxy to "splay" on the inside, forming an nice seal on the interior of the crack. Never did leak again.

It's too bad you only got 200K miles out of the first one. You suppose it's still under warranty?

__________________
Jackson
Rockford, Michigan

1985 500SE gray market
1982 Porsche 928
1985 Mercedes 300CD X 2