123pugsy

I ordered an M12 x 1.5 to 3/8" adapter for my 5.3 swap for my original temp gauge.
Gonna stick it in the rear of passenger head.
Just realized my car uses one in 1/2" size.
Anyone know of a 3/8" sender that is close in ohms to suit?

garys 68

iTrader: (1)

There's a brass block plug on the rear passenger side of the block. I drilled and tapped for a 1/2" NPT sender on my 68 corvette.

123pugsy

Thanks but I won't be drilling and tapping at this point.
I can get a 3/8 sender and add resisters in line to get close.
I have no problem doing this. Just need to find one in 3/8 size relatively close in ohms to what a 69 Chevelle uses.

garys 68

iTrader: (1)

See this thread:
https://ls1tech.com/forums/conversio...auge-59-a.html
Btw, you only have to drill and tap a $10 brass screw in block plug, not the block.

123pugsy

I found the plug in the pic attached beside the crank sensor.
Are you saying to drill and tap that plug? It looks about 1/2" NPT size already at the most.

123pugsy

Funny you mention.....I was reading this thread this morning at my office.

garys 68

iTrader: (1)

Thinking that's the drivers side, but I used the passenger side. But just a screw in brass plug, easy to drill and tap.

123pugsy

Thanks.

Passenger side, but no matter. There's a huge one on the driver's side that I couldn't get out during the rebuild.
I got pissed and got to work in the garage.
I will pick up a stainless 1/2" coupling in the morning and weld it on to this adapter I made up.

Michael Yount

iTrader: (1)

Ideally you want to sense temp where coolant is leaving the system to head to the rad - AFTER it’s picked up all the heat.

123pugsy

The end result in case someone wants to make their own adapter.

123pugsy

Thanks.

I'll have to try it and see how it works.
I've read a lot of guys are using the passenger side head hole.

Michael Yount

iTrader: (1)

Lots of folks use it because it's there - relatively easy to use. It will give you a temp reading just fine -- just know that whatever temp your gauge is showing - there's a higher temp at the front of the head. That's why the factory coolant temp sensor is there on the driver's side. I had a fitting welded into the radiator tank right where the hose with hot coolant coming in from the pump connects -- sensing the highest temp available. That way you know you've got worst case.