Carrera GT

As you note, the different alloys are not going to cooperate with a simple tack/spot weld. And access doesn't look good for a skilled TIG operator to get in there, clean the adjacent surfaces and get metal penetration ... you still have to get the part out of the car and on a bench, I think. The welds can still fatigue with the expansion, heat cycling and that bloody big hose bending around.

Step one is probably to secure the hose from "working" on the fitting. This reminds me of a common problem that what looks "good" on the hoist, doesn't reflect what happens when the engine torques the mounts over and everything gets stretched one way or the other. If each of the hoses that connect to the fittings that have failed are presently on a bracket connected to the firewall, perhaps they should relocate those brackets to the engine to stop the relative movement.

AllanJ

Welding aluminum successfully requires it to be super clean. BTDT (I'm an amateur welder - far from a pro.) Engine out. No way around it. It won't be cheap, but that's what I'm doing. I don't want more joints/connections added to the equation. I want fewer joints. To me that means welding, nothing else.

btw, do you know what alloys are used with these two parts (casting and tubing) that you have concerns about? Many different alloys can be welded together (4043 is a great general purpose filler rod) so I was wondering what was on your mind.

Cheers,

deputydog95

Well, my engine is currently out. For now. But I don't have much time to make up my mind as the parts are on their way from Germany.

Nobody I've spoken to locally likes the welding idea because of the different metals. Concerns are that the weld would fail, and the overheated epoxy (as a result of the welding) would let go too.

Then again I am not a mechanic or a welder so please don't listen to anything I have to say

andrew2008

If the main reason not to weld is the different metals, it might be possible
to get some fittings of the appropriate shape and size which are made from
a compatible metal. Considering the time, expense and safety issues, buying
6 more fittings may be worth it.

deputydog95

You bring up a great point. I think part of the problem is that the block is cast and the couplings are extruded. Not only different alloys but different production process. This is probably why Porsche just glues them in

Bob Rouleau

I don't see tack welding as a solution. When the glue lets go, the tack weld will hold the fitting in place but fluid is going to leak anyway. When mine blew out, the fit into the water pump was loose, i.e., the glue seals the thing.

AllanJ

You can weld many different aluminum alloys together. Not all are compatible, but the cast aluminum is probably of the 4xxx series and the tubing is probably the 6xxx series. 4043 filler rod is compatible with both. 4047 might be a better choice but I'm not an aluminum welder guy. I've only done a tiny bit of aluminum welding with a MIG and 5356 filler. That definitely won't work in this situation.

I just found out about the sloppy fit of some fittings from a local shop. I'd weld the entire perimeter knowing that.

Cheers,

GG300

Eurotech, 508-879-9911 in MA does a great job of tig welding the coolant joints. ON this web site go to search type in eurotech click on coolant systems solutions go to the 2nd page for your answers. TO me this is the only correct fix.
Regards
GG300

Carrera GT

Links to suggested answers:

https://rennlist.com/forums/997-gt2-...solutions.html


specific post:
https://rennlist.com/forums/7630503-post16.html

(speaking from several years of practicing TIG myself, the welds look perfect)

Seems to me like the alternative of getting parts that are one-piece forged/cast from another version of the GT1 is more appealing.
And going to electric power steering pump.
And going to electric a/c compressor
And, and, and ...

AllanJ

Shop called. Signs of coolant leakage are evident on my car. I'm getting the bleeping things welded in place.

roberga

were you at Pacific yesterday? Saw the silver and OrangeRS stuck in traffic last night.

AllanJ

Nope. Haven't been there since July. When I'm there next I'll have shocks that work and coolant staying in my car, guaran-TIG-ing-teed.

Carrera GT

Ironically, that's really good news for the rest of us! Please have them photograph the leaks and get a Porsche regional service supervisor to see the car before it's touched. They don't have documented incidents and it will make the world of difference to see these being properly documented.

va122

ok this is freaking me out now. I saw some coolant on the floor of the garage behind the left rear. I called my shop and they said that they pressure tested the system and it was fine and replaced the top hoses already. It was probably overfill as they topped off the coolant. Should I be concerned? I'm at the track now!

996FLT6

Plastic tank cracked? Mike