SteveS83

So I was ready to pull the trigger on purchasing the Europipe stage 1 exhaust and UMW tune from Kevin, however I’ve been reading a lot about the coolant fitting issue that could potentially occur. From what I’ve read – this is mostly an issue with cars that are regularly tracked, which I will not be doing. Of course I’ll probably run a few HPDE track days here and there with PCA or another club, so I don’t know if solidifying the coolant fittings are necessary in my case. However, adding the EP + tune will add more power to the car. Now, I’m no mechanic but I’d think more power equals greater pressure on the engine, thus increasing the risk of a failure with the fittings. Whether or not this assessment is correct – no idea.
I can’t do everything on this car right now, so having to prioritize these items, what would be the logical sequence? If pinning or welding or whatever is done to these fittings is priority, what else should I address while doing this work? The car is a 2007 with 49k miles. Plugs were done 7k miles ago and the clutch has good grab down low. I will replace trans & engine mounts with OEM regardless of the work I do.

Suggestions?

Skwerl

From what I've seen, coolant pipe problems can befall anyone, not just tracked cars, and honestly, an 07 with 50k miles is probably getting into the Danger Zone. Seems like most people run into it between 45-70k miles.

That said, and I'm not a mechanic either, I doubt an exhaust and UMW tune will increase the odds of it happening. It's mostly a function of heat cycles and age rather than power. The coolant doesn't run through at a particularly high PSI.

6Mezger

JG 996T

I suggest you buy the EP and tune from Kevin. ^ really know way of predicting if or when hoses go and not a good reason IMO to not enjoy those great add ons.

SteveS83

I'll eventually get the EP & UMW tune but it may be later this year or next year. The car has plenty of power for me right now, but the thought of the sound of that EP has me itching....
I see you're in Northern NJ as well. Do you use an indy shop, if so who do you recommend?

SteveS83

Can you reuse the same fittings or just buy new? Are the OEM fitting plastic - hence the reason for the glue? What's the difference or even advantages between welding and pinning? What's the cost for this work?

JG 996T

cstyles

If you're not going to be tracking the car, preemptively pinning or welding the coolant lines is overkill IMO. The failure is not catastrophic if it does occur to you. So if it fails, fix it - and fix it right so it never happens again. However if you are tracking your car, you owe it to all the other participants to either have the work done or not run coolant at the track. I personally am running water wetter at the track instead of preemptively doing the coolant lines. If I experience a failure then I will have the work done. If not, I will do them when I upgrade my clutch at some point.

There are two schools of thought when it comes to pinning vs welding. Pinning is a much more simple procedure. It ensures that the hose will not release from the fitting in the event the adhesive fails, but pinning will not stop a leak from occurring in the event of an adhesive failure. In order to repair the leak, if it ever did occur, you're doing the whole engine out service all over again. That said, Sharkwerks recommends that pinning is the best solution and that they have completed 60 cars and not a single one has ever leaked - even 50,000+ miles since the service. I'd be inclined to trust their advice as they're one of the most reputable Porsche shops in the world.

Welding in theory sounds better but there's potential for the weld to crack. Also, it's apparently a tough job to weld even for the most experienced welders. Welding aluminum to cast, different expansion properties, etc...

Edit: Copied from Sharkwerk's website on this very topic:

Something that has gained a lot of popularity in recent months is the welding of these coolant lines, instead of pinning as we recommend. It might sound like an appealing solution, as a proper weld is nearly unbreakable. However we believe this is missing the point of the issue and is a riskier and possibly less reliable solution.

We've now seen at least three cars come in with welded lines that are leaking and so we discourage this practice. Each fix was done by a "top" welder or reputable independent Porsche tuner in our area. The weld fixes will show porosity (air pockets) or cracks in different places, and coolant will seep or drip, with pink cloudy residue near the welded lines. Some have lasted under 1000 miles.

We have seen welded lines that appear to be holding up fine, so we would not discredit the choice, but we also believe the pinning to be 100% reliable if done right.

We believe that welding is approaching the problem from the wrong angle: the problem is not that the coolant escapes around the tube (through the gap occupied by the glue) and it never has been: so welding and patching up the gap there is pointless.

The whole problem is the tubes eject from the engine causing massive coolant loss. Just locking those tubes in, with even the old factory glue, is sufficient to prevent a leak for the life of the vehicle. We have re-inspected our pinned lines on cars 50,000 miles later and the result is unchanged. Welds on the other hand on these pieces may eventually crack as the pipes and cast pieces heat and cool over the years at different rates.

As the temperature of the engine rises from ambient (0-40F degrees in winter perhaps) to operating temperature (210F+) the different metals in the pipe, cast piece and weld will all expand at different rates. This is where that factory glue (that is often criticized) works well: it is a great material for its expansion properties. It will expand evenly and turn softer. However if welded and fixed in place, the aluminum tubes, cast housings and weld material will contrast and expand at different rates. This may lead to cracking and failures as the pieces cannot flex or stretch evenly. Also, new weaknesses may be added to the factory pieces that were never a problem before.

Locally we have performed over 40 of the pinning fixes (probably closer to 60) and not one has leaked since the installation: we regularly see these cars for updates and inspections when doing other installations. The pins will never break and the glue should never leak.

Since it's unnecessary to weld in the first place, why make such a mess of your stock parts and permanently modify all those parts? In addition to the reasons above (missing the point of the problem) - the issue is that welding a thin metal tube (or thick in the case of the aftermarket ones) to a soft/porous cast housing is just a recipe for disaster. You simply cannot get the penetration right on both surfaces simultaneously, it's almost certain that your weld will penetrate through the cast piece easily (like a marshmallow) and have a hard time going through the tube (which is more like a very hard cheese). It will look like it's sticking to it but that's not how a weld works: unless you can inspect both sides of the weld you can't be certain it actually took. Even if it does, you cannot be sure that the weld will last, since this piece is constantly changing shape and size with temperature and each piece will change at different rates.

To reiterate, this is why as long term owners and enthusiasts for 996 and 997 GT3 and Turbo models, we do not recommend the "weld" fix for coolant repair and do not perform this repair in house.

F1CrazyDriver

Having been around the block more then once.
Preventive cost less.
Did i also mentioned how much less stressful it's not having to deal with the situation when one coolant line fails?

SteveS83

Yes I'm a member for a few months now. I never heard of Aspen but they're close to the MVC. PowerTech in Rockaway did my PPI and the guys were really cool - but I've heard mixed reviews on them. I know they're Porsche specific and have been doing it for a long time. I have no experience with them so can't say one way or the other. I was going to take a ride to CT to see family and check out Daniel Jacobs about this. I heard they're a great shop as well.

I'll be doing my oil for the first time tomorrow. I'll tackle the diffs, AWD controller, and transmission when I can get to my buddy's lift.

SteveS83

@cstyles - Good info thank you. Is pinning these lines something most any indy shop can handle or is this specific to certain SMEs?

cstyles

I honestly don't know. I am in the same predicament - my indy that I go to for all my PM service needs is excellent, thorough and fairly priced. But he hasn't done a Mezger coolant pipe job (he's a mostly air-cooled shop). He has told me that is isn't a big job (to him) and that the motor re & re is the majority of the work required. I haven't decided yet if I will use him for it or whether I will take it to a motorsport shop that has done this many times (and will charge me far more $$$ for it presumably although I haven't gotten a quote yet). My gut is leaning towards using the shop that has lots of experience doing the pinning.

robhamster

so my '07 leaked fluids starting at 45K miles and at 49K miles I had the fittings welded and Sharkwerk elbows. This is my car, not an investment. I never wanted to see this problem again. Interesting that post from Sharkwerks concerning welding. I have 13K miles on the repair and no problems. I drive this car, but I do not nor have I ever tracked this car. Do what makes the most sense to you. I just struggled with sticking more epoxy in those joints.

cstyles

I agree in some cases - for example, the IMS fix on the M96 motors. $4k PM job versus $20k motor rebuild.

In the case of the Mezger coolant line issue, what is more expensive to repair after the fact versus doing the job as PM? I'm genuinely curious. While of course a complete failure is going to lead to some inconvenience, my understanding is it's the same job whether it's done as PM or repair. Also, many times the coolant lines don't release and dump the whole load of coolant - often the problem is spotted with a coolant leak first, and is addressed before complete failure.

Nate Tempest

This is especially true on the later years (2009 and late 2008 models). A different epoxy was used, so it's much less likely to let go. The plastic elbows will start to slowly leak after a while though. I decided to replace them with metal at about 48k miles while doing clutch and plugs, and found signs of slight leakage. Obviously pinned the lines at the same time, because why not. But yeah, I can't see why it would be more expensive to repair after a significant leak—unless you get really unlucky and dump coolant onto your rear wheels, or in front of someone else. Again though, I think a catastrophic failure in a car that's got the newer epoxy, or probably on any car not on a track, is unlikely.