jittsl

Earlier this year I sold my first 6GT3 to a friend of mine. In the whole time I had owned the car (6 years and 20000 track miles) the car had given me absolutely no problems whatsoever.

Recently however, while circulating Harris Hill (Texas) at a DE, my friend suffered the familiar blown off coolant hose in the engine bay. Fortunately (it was thought) the steam was seen early and the car was stopped on track instantly. Normally this wouldn't be a huge deal except that after the initial repair was completed (aluminum pipe welded into block) he drove it home only to discover fluids still coming from the engine and dropping on the floor. The initial diagnosis was that in an unrelated incident the crank seal at the pulley end had started leaking oil and this was the cause of the issue. After some discussion the dealer was given the go ahead to repair the seal (another $2k on top of the first). Whilst the car was on the lift it was further discovered that water is also leaking from the head gasket and (claimed) from the gasket at the base of the cylinders (which I didn't think existed on a GT3). the dealer now believes the engine has been baked and will require a complete tear down. The bill will almost certainly total into the 5 figures.

My friend holds no grudge towards me over this but as a concerned bystander I am wondering if this makes any sense to you experts out there. My specific questions are:

Has any one else had the issue that a fluid leak has led to a complete rebuild? I have seen a couple of GT3s puke their guts but it seems that usually post repair they are back to normal.

Secondly, does it make sense that the car should suffer a major overheat (presuming it did) and then be up on a hoist, inspected, repaired with no sign of leaks from the seals or gaskets and then develop these leaks afterwards? That just doesn't seem right to me.

Thanks for any insight or help.

Serge944

Each cylinder liner has two O rings at its base to prevent coolant mixing with oil. If they are indeed leaking, the engine certainly needs a rebuild.

How did they determine this? Condensation on the oil filler cap? Drained the oil?

996FLT6

Any other warning signs on car(dash idiot display) other then coolant level low? That sucks. Never heard of that happening unless it was driven for a long period of time wo knowing it. Other then noticing oil leak how did it drive? Mike

Rob S

Any idea how long it was run after the coolant pipe failure occurred? Do you know if a leakdown test has been conducted? I would agree that if there's leakage where they seem to be reporting it, then that's not a good sign and a teardown may be in order. But it is odd that this wouldn't have presented itself immediately.

enthusiast

This situation does not make sense, in that all of a sudden so many seals let go. I would take the car to another shop that knows this engine and have them examine it. 20,000 track miles is a lot.

One of the reasons many of us bought this model is the wonderful engine.

jittsl

I am waiting to speak to my friend so I can get completely accurate answers to the questions asked above. As I understood it however, the car was shut down in a matter of seconds of the first sighting of steam coming from the rear, and I believe it ran perfectly on the trip home and back to the shop after the first repair. I don't know yet what the situation was with idiot lights.

FFaust

Very intriguing.

jittsl

After checking my facts it appears that statements above are true. The only additional information is that the only idiot light noticed after the car was stopped was the red temperature light.

996FLT6

I sprayed coolant(water plus water wetter) about half-mile strip on track and did not know I was spraying it til I got meatballed- looked at my dash "coolant level low" and water temp glowed red. The thing I'm having a tough time if engine did bake it would rear it's ugly head pretty quickly if it ran for a longtime wo coolant- u be hearing some major knocking or total seize of motor. My car is getting the whole press fitting and all new hoses/plumbing replaced. I'm crossing my fingers mine hasnt baked. Please keep us updated as well as I will also. Mike

tdf360

Was this THill with CFRA a few weeks ago?

996FLT6

No mine happened a few months ago at a NASA event. So another one blew with cfra? Mike

tdf360

Actually, it was a 996TT, not a GT3...

Rob S

The details here are important, and we may never know some of them. It depends on how long the engine was run at high load after a significant amount of coolant escaped. If it was run at high load for 10 seconds after the coolant first escaped, even if it was all dumped out at that instant, I would think that wouldn't cause a problem. But if there was a loss for several minutes that went unnoticed, even if it was shut down seconds after being noticed, there would be higher potential for damage. You'd think that steam would be evident immediately, but you never know how quickly it appeared, was noticed, and was acted on.

And though it was reported to have run perfectly on the trip home and back to the shop after the coolant pipe repair, one wonders whether there was actually a coolant leak at the heads that went unnoticed at that time. Maybe damage was done during the track coolant loss that wasn't seen until the car was driven a bit and heat cycled a few times.

Also, in your first post, you talked about the crank seal repair that was apparently unrelated, and that it was diagnosed after the coolant pipe repair because "fluids" were found on the floor. What fluids and where were they found? If it was just oil from the leaking crank seal then that's logicial. But if the fluids included coolant, and came from further outboard on the engine, then it might suggest that the head gasket(s) or cylinder base gaskets were leaking at that time too, which might point back to an overheat on the track. I'm not familiar with how a head gasket leak manfests on a GT3, but they can typically cause an internal or external leak of either coolant or oil, or both. And the rate of fluid loss might be quite small, such that it wasn't noticeable to the driver.

No matter what the reason, unfortunately, a teardown is likely in order if the leaks you describe are present. Damage may be minor to metal parts, but it could be that resealing and retorquing, at least, will be needed. I still think that a leakdown of the engine should be conducted, as well as a coolant system pressure (or vacuum) test to see if leak locations can be confirmed.

Interesting problem. Please keep us posted on the outcome.

Rob