Thermostat - 302

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Parkka

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I have been told by many to drill a 1/8" hole at the upper edge of the thermostat before placing it in the housing to alleviate the initial pressure.  However, the new one I purchased does not have a hole and I cannot find a thermostat for a 73' 302 anywhere with a pre-drilled hole.  There are also no mention of drilling a hole in any of the old repair manuals for the car 

Is this recommended?  If the hole is drilled, what are the consequences?

Thanks,     :thankyouyellow:

Dan

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Hemikiller

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The idea behind the hole is to allow any air to bleed out of the intake before the t-stat opens. This prevents the initial huge "burp" as the trapped air comes blasting out the top radiator hose.

There is no downside to drilling the hole. Just get a good quality t-stat and do the deed. When you install it, put the hole at the 12 o'clock position.

 

Parkka

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The idea behind the hole is to allow any air to bleed out of the intake before the t-stat opens. This prevents the initial huge "burp" as the trapped air comes blasting out the top radiator hose.

There is no downside to drilling the hole. Just get a good quality t-stat and do the deed. When you install it, put the hole at the 12 o'clock position.
 

delawarebill

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the best place to drill the 1/8 in hole is between the "Y". and have it at 12 like mentioned. also if u install with the "Y opening at the top and get a new stat housing with a access hole on top u can put in a temp gage there and not hit anything. so no removal and placement of stat housing once done.

 

Parkka

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thank you.  Never thought about putting a temp gauge there said:
the best place to drill the 1/8 in hole is between the "Y". and have it at 12 like mentioned. also if u install with the "Y opening at the top and get a new stat housing with a access hole on top u can put in a temp gage there and not hit anything. so no removal and placement of stat housing once done.
 
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