RBLUVETT

I had the thermostat replaced as part of a tune a couple of months ago, and now there is a slight leak at the base of the housing. Not a big leak, perhaps a tablespoon or two on the garage floor after a drive. If I place my finger at the bottom of the housing it is wet. I re-torqed the two bolts to 10 lb/ft as specified in the manual, but still have the leak. Any ideas? Anybody else had this?

Daytona Bob

I haven't changed one in ages... Isn't there a Gasket involved?

I need to do a 160 myself.

Maybe someone can chime in on the procedure / parts involved in the process.

This will help you determine the leak cause.

Capt Steve

There is an O-ring that goes into a groove on the thermostat housing. If that O-ring is not seated correctly or has been pinched, you will get a leak.
Remove the thermostat housing and check the O-ring. If it has been pinched, replace it with a new one. Tighten the bolts to 11ft/lbs.

KENZ51

The O-ring stays on the thermostat, Not a bad job to do but wouldnt you want to take it back to who did it in the first place? If they Over Tightened it, it could have done damage to the housing! Good Luck!

Eritosthenes

Chuck (of CoW) once mentioned a gasket problem that sometimes occurs when a 160-degree thermostat is installed. If I recall correctly, there's an alignment that must be made and if it's not done just right, the result will be a leak like yours.

HANNY

a guy could put one in wrong but it would leak like crazy from the start. not your case tho, you need a new t-stat gasket. Just get it redone, just a gasket failure. paul

Motorhead-47

2009 LS3's take a different thermostat than the 2005-2008 LSx's. You in all likelihood have the wrong thermostat.

2009 SLP Part # is 100229
2005-2008 SLP Part # is 100228 (it is physically smaller)

See my thread from a couple of weeks ago on this issue...

http://forums.corvetteforum.com/c6-t...t-fitment.html

StoplightWarrior

I had the exact same prob with mine. Had to completely redo the install and reseat the gasket, but no problems since. Good luck!

Cherokee Nation

My 2008 has a LS2 water pump.

Cherokee Nation

I've changed out my stat 3 times with no leaks.Make sure to clean the stat housing where the "0' ring seats into and also use a piece of sandpaper on the water pump input then wipe with a rag and reinstall.

EVRose

8-1/2 year old thread.

Mike's LS3

Yes, old thread but good information is helpful for others.

There is a notch in the seal that properly aligns the thermostat in the t-stat housing for correct flow direction. If not aligned, the t-stat will not sit properly in the housing and may cause a leak.

Make sure you have the correct water pump and t-stat. In 2009 the water pump design changed to accommodate the LS9's supercharger.