Coolant Leaking Near Firewall - Page 2 - PeachParts Mercedes-Benz Forum

Toran · #16 08-24-2025, 09:09 PM

Yep, turned out I have a tiny rust hole located at the rear of the upper pipe. I will follow your advise while repairing it. Meanwhile I was able to switch out the metal pipe for some 3/4 and 5/8 silicon heater hose. It really is a tight area to work in especially when removing / adding hose clamps.

Hopefully this can help another person along the path. While there is another way this is what I did to keep the car on the road.

5cylinder · #17 08-25-2025, 07:32 AM

Thank you for photographing and carefully annotating - very helpful.

Diesel911 · #18 08-25-2025, 12:45 PM

Quote:

Originally Posted by jagboy69

Dammit... I was hoping it wasn't going to be your pipe. I would try the jb weld route before anything else. Scuff it gently with some 60 grit paper, wipe it super clean with acetone and try JB weld. If it's a pin hole, put a decent sized blob over the hole. About the size of a quarter! And whatever you do, do not use fast set JB weld. I think that's the 5 minute stuff.. It's total garbage. Mix it evenly, give it a couple of minutes to stiffen up then apply it to your pipe. Give that thing at least 24hrs to setup before allowing water back into that pipe. This should get you back mobile again, meanwhile, maybe you can source a new pipe. If you wanna go in the business of making a nice stainless solution, I will be your first customer! Good luck! If it doesn't work, you can always try hose and a Y. That would work too. I wanna say 5/8" hose is the right size, but I wouldn't bet vital parts of my anatomy on that one... lol

Brake cleaner is what I use to degrease areas to be JB Welded. Also, I remind people to use the slow curing JB weld for repairs where there is heat. The heat it can stand up to is on the box. Give it the full cure time.

jagboy69 · #19 08-26-2025, 02:56 AM

Yeah Ive had no luck with the 5min jb weld either.

jagboy69 · #20 08-26-2025, 02:59 AM

Hey great job with that photo and description. Im confident I could easily remake that thing out of some copper pipe. I hate working stainless anyways.

Toran · #21 08-26-2025, 04:07 AM

Thank you Everyone for the constructive feedback!

jagboy69, we are waiting to see that shiny copper version

jagboy69 · #22 08-28-2025, 01:36 AM

Mine hasn't sprung a leak >>> YET! But I'm sure it's day is coming. Saw quite a bit of corrosion inside that pipe last time I looked.

I hate cutting pipe so it fits with another pipe at weird angles. Kinda like cutting crown molding to fit a sloped ceiling. The section over my fire place is about 10ft long and I swear I burned through 4 trees making it correct. lmao.