Where to put water temp sensor?

[DanEC]

Originally Posted by patrickt

This page says that UNF threads can only be used with other UNF threads....
McMaster-Carr

I don't think these are a fine thread tapping. I'm beginning to suspect they may just be a standard coarse UNC tapping (non-tapered) opening.

[patrickt]

Originally Posted by DanEC

I don't think these are a fine thread tapping. I'm beginning to suspect they may just be a standard coarse UNC tapping (non-tapered) opening.

Dunno... but all the Smiths stuff at Gauge Guys comes in BSP and UNF. Smiths Classic Gauges

[patrickt]

This is from Caerbont. I think I remember Bob, Peter, or Doug telling me they built the Smiths gauges that were in my car.



Source: Water Temperature Sender

[DanEC]

Well I didn't remember it looking like a fine thread fitting but maybe it is and the large diameter is throwing me off. Don't work with 5/8 inch bolts every day. Anyway, I will match it up and come up with something that works.

Thanks

[patrickt]

Originally Posted by DanEC

Well I didn't remember it looking like a fine thread fitting but maybe it is and the large diameter is throwing me off. Don't work with 5/8 inch bolts every day. Anyway, I will match it up and come up with something that works.

ehhh, I'd just sink it in a pool of JB Weld.

[DanEC]

I double checked it when I got home and it looks like a 5/8-18 UNF thread adaptor. So much for my 61 year old brain cells. The hieater nipple does look to be slightly tapered so it is probably a NPT piece - but I'm banking on the manifolds being a straight UNF tapping. No luck at Sears but I found a tap and 37/64 drill bit at McMaster-Carr and ordered it. So, with a little luck the JB Weld can stay put away.

[DanEC]

One more question on this subject. I received my UFC 5/8 inch tap from McMaster Car today and it mikes out at .63 inch on outside of the cutting edges. The temp and oil sender fittings mike out at .66 inch OD. Does a .03 inch interference fit seem unusual for a treaded fitting like this? I assumed they would be closer in diameter or identical and I definately don't want to accidently crack this old intake.

Thanks