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kazoocruiser · 09-26-2018, 02:55 PM

Hi 83GMCK 2500,

I just sent a message to the seller of the switch on Ebay you sent me the link for, to see if he could put a wrench across the flats of what he has to see if it is the same size as what is in there now.

I don't know what the thread pitch is on what I have, but I am pretty sure, because what I have now is 3/4" across the flats, that if I get something with 7/8" across the flats, that I am going to have to either use an adapter, or try to use the thermostat housing.

Thanks for the detailed help. The difference between a normal ported vacuum switch, which is normally closed until a certain temperature is reached, and what I need, which is an EFE, is that an EFE switch passes vacuum until a certain temperature is reached, when the vacuum is then shut off.

09-26-2018, 02:55 PM	#7
kazoocruiser Registered User Join Date: Aug 2018 Location: Bronx, NY Posts: 215	Re: Need help locating an obsolete part Hi 83GMCK 2500, I just sent a message to the seller of the switch on Ebay you sent me the link for, to see if he could put a wrench across the flats of what he has to see if it is the same size as what is in there now. I don't know what the thread pitch is on what I have, but I am pretty sure, because what I have now is 3/4" across the flats, that if I get something with 7/8" across the flats, that I am going to have to either use an adapter, or try to use the thermostat housing. Thanks for the detailed help. The difference between a normal ported vacuum switch, which is normally closed until a certain temperature is reached, and what I need, which is an EFE, is that an EFE switch passes vacuum until a certain temperature is reached, when the vacuum is then shut off.