Sump plugs - threadsize?

[Richard_M]

I need to site an oil temp sensor in my sump - and am thinking that an adapter on the plug is the easiest way - I don't want to mess with the sump itself if I can help it, it's race baffled.

So - Demon Tweeks among others will charge me 20% above the going rate - but what thread size do I need? And isn't it tapered?

Thanks

Richard

[Martyn GT6]

Its 1/2", you can get a thermostst pocket in that size and it would work.

[CharlieB]

217 wrote:

Its 1/2"...

No it isn't its 5/8" UNF.
The female thread in the sump is parallel & the plug is taper. Some US cars had parallel plugs with copper washers according to the parts catalogue.

[Steve AKA vitessesteve]

Alternately could you  fit a t-piece to the oil pressure sensor on the side of the block to pick up the oil temp.  I run a oil pressure gauge that way.

[esxefi]

richard,

what gauge are you going to use,electric or capillary type.

if using the former you could use the dipstick tube type sensor.

[Martyn GT6]

oops!!! I Stand corrected.

[Richard_M]

The sensor is electrical.

I currently have it in a T tube off the usual spot with the oil pressure switch. The capillary oil pressure gauge is run off one of the other taps on the block.

But the oil temp gauge won't work here. I figure its not actually immersed in the oil, as there is air in the T piece, which becomes pressurised by the oil - so the pressure switch works, but not the temp gauge.

I've come to this conclusion having checked the sensor for correct resistance (using hot water) and checked the gauge out of the car with local wiring. I've checked the car wiring too.

Its turned into one of those very frustrating jobs that should be simple, but ain't!

A dipstick solution might be good - it's not my fist choice to start playing with sump plug adapters - on a race car!

Richard