2 Questions: (External T-stat leak and possibly inoperable)

[ScottArizona]

Hey guys, when I got my car there was a lot of oil around the external t-stat in the passenger wheel well. Cleaned it all up and got it bone dry. The leak is definitely not coming from any lines, but rather that large slotted cap. Here are my questions:

1) Is that leak usually fixable by just replacing the cap and sealing ring? I realize I likely won't be able to get it off while the thermostat is in the car, so I'm going to bite the bullet and remove all the non-leaking lines and remove the thermostat from the car and go to town with a pipe wrench, etc.... Before I do that, however, does anyone have any tricks for removing that sucker in-situ? I don't want to destroy anything but if there is a trick, I might try that first since I hate disturbing non-leaking stuff (P.O. previously installed the finned Elephant Racing lines).

2) In the several months I have had my car, it has never once exceeded 180 degrees on my dash gauge. Granted, its winter (in Arizona), and I don't drive it very hard and not often in bad traffic, but that just seems strange. And, I have never detected any warmth whatsoever in the lines going from the t-sat to my aftermarket front wheel well cooler. Not once. Even when engine is nice and warm. What to check? Seems that if the oil is never hitting 180 degrees, then the fact that the t-stat wouldn't open is normal. But, why isn't my car getting hotter? Some other culprit?

Thanks in advance for all your help!

[75 911s]

I'm in the same boat weather wise here in Vegas. The cooler should open up after a few minutes of accelerating and normal driving. Even in winter driving (Southwest winter that is), the engine goes past 185 pretty quickly, but with my front cooler, hangs out in that area once the front lines are operating and my Carrera cooler / fan is engaged.

Since you are opening up the T-stat anyway, good chance to check it with a thermoter and pot of water. I was able to get my cap off using a rag to protect the finish and a big pipe wrench and a vise to carefully hold the t-stat (another rag wrapping the t-stat) I think I pre-soaked with kroil as well.

If you damage the cap, there's a custom made cap that a pelican sells that has a hex drive on it so it can be removed on the car much easier.

[KTL]

Yes there should be nothing more to that leaking cap than replacing the seal ring. Honestly you should not be experiencing a leak there because the machined surfaces (underside of cap, face of t-stat opening) are usually very good. I suspect someone may have replaced the regulator unit when the finned lines were installed and didn't do a good job of tightening the cap. I wouldn't be surprised if you find the cap quite easy to get off in-situ, since it's leaking. That leads me to believe it's not all that tight and should come off no problem.

The slotted cap is a joke in terms of its function for loosening or tightening the cap. The pipe wrench is indeed the way to go and install a new cap with hex tooling. JimmyT here on the forums sells a very nicely made hex cap for a fair price. Super nice guy and very talented.

Since your SC doesn't even have an actual oil cooler, but instead just a cooling loop, i'm really surprised you never see temps above 180. I would do some investigating and see if the temperature gauge and the sending unit in the engine case are a proper match. I also would remove and test your thermostat within the engine (in the infamous "triangle of death" atop the engine) to see if it's staying in the hot position. If it's always in hot mode, the oil cooler on the engine is always seeing oil directed through it and that may keep the engine from warming up

[ScottArizona]

Thanks guys! Will dive in and report back!