I remember reading a while ago about drilling 1/8" holes in the thermostat to allow some coolant flow through the t-stat at all times. The idea was to help make sure no air pockets develop though it would take a little longer for the motor to warm up.

I couldn't find anything using a search, so can someone post where these holes go for me? It seems like it would be really easy have a tear start around the hole. I don't recall any reinforcement around the hole, but it was quite some time ago.

Here is how the waterpump folks do it: http://www.stewartcomponents.com/techtip3.htm


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Rick
72 El Camino (http://members.home.net/jimmy4/rick1972elky.html)
TPI 350/700r4 (http://chevelles.com/showroom/ricks%20motor%20-L)

I was looking at that the other day to be honest, but I'm hoping to do this with a regular thermostat, not the Robert Shaw. This is on my 93 Jeep Cherokee, which in hindsight I should have mentioned earlier, but the idea is the same. I guess I can see if Robert Shaw makes them for Jeeps also. Anybody know a supplier's web site?

68sedan. I think you are mixing apples and oranges. The 1/8" hole in the thermostat was devised for applications where when filling a coolant system there was a problem with underfilling due to an air lock in the engine. The 1/8" hole allowed the engine to fill with coolant properly with no air voids developing.

If you really need to drill holes in your thermostat to achieve adequate cooling then you have something else wrong with your cooling system.

If your cooling system is properly filled the only way for air pockets to form is if coolant leaks out since the system is a closed system. Additionally since your system is a bottom suction system the small amount of air in the upper portion of your radiator stays in the upper portion of the radiator. It does not become an air pocket problem.

I see what your saying Charbilly2001. This didn't all start b/c i'm having a cooling problem, I was just planning on doing the thermostat when I changed the fluid which is probably due. I had been reading the Stewart Components page and came across the T-Stat that rick pointed out to me and thought it would be a good idea for the Jeep.

The truck runs strong at 210, so I'll just replace the T-stat with a new one and leave it at that. Thanks for the replies!

Air lock can be a big problem especially with many newer model cars. Without getting into details a good radiator shop should have a system to eliminate them. For our old Chevy purposes a couple of hot/ cold cycles should eliminate the probem if one tops of the system after it cools. I mean like after overnight cooling not just 30 minutes.

Robertshaw thermostat; Autozone. Has a small relief hole built-in. Highly recommended. Search this site for a year or so back.

My $0.02