Stacking crush washers on temp sensor?

[rjd2]

Hi folks-I have a spare coolant sensor here, which threads fit the plug on the passenger side of the block(see pic for location). I am considering trying to seat it in the block. I dont have the plug on hand, but could of course get one. Seating a sensor here, it feels like it is feeling some resistance maybe 1-2mm short of seating fully. If I stacked a few crush washers, it would go flush. Is this a terrible idea for any reason? If I used teflon tape, am I just begging for a leak? As much time as I have spent shooting temps with a gun on the upper and lower parts of engines to chase overheating problems, my dream would be to have an actual "numbered" meter reading at two locations in the cooling system that I could read from the cabin. Thoughts?

[jimk]

Teflon tape will not seal straight threads, it is meant for tapered pipe threads.

 

Stacking washers might provide a seal but I wouldn't want the sensor to back out and dump ALL the coolant, cause it's the block drain.

[TobyB]

While I agree with Jim in principle, I think in practice you'd be fine.

(it's not tapered, it's meant for a flat seal, though)

Ideally, you'd run a thread chaser through it, but finding one for that thread?

Me, I'd clean it out well, figure out my crush washer stack, and then add a 

bit of blue loc-tite just to help me sleep at night.

 

I do wonder what you'd get for temps- that's kind of the appendix of the water flow, back there.

 

t

 

 

[ray_]

A man with two watches is never sure what time it is!

 

😎

[Mike Self]

Were it mine, I'd replace the bolt with a drain cock that has a nipple, allowing you to drain the block using a small diameter hose and a basin, rather than having antifreeze run all over the place.  I took the bolt with me to an auto parts store and found a drain cock whose threads matched up just fine.  Hasn't leaked in all those years since I installed it.

 

And I agree with Toby--that's not the best place to obtain coolant temps--you want it where the factory located it--where the coolant is the hottest, just before entering the top of the radiator.

 

mike

[Son of Marty]

Yeah not a real good place for a sender the drain, for obvious reasons, is set at the very bottom of the water jacket, that might be what the obstruction is.

2 hours ago, ray_ said:

A man with two watches is never sure what time it is!

 

I one bought a 19 foot fishing boat where the PO had installed 3 compasses on the dash, I mean WTF direction are we really going?

[ray_]

10 minutes ago, Son of Marty said:

Yeah not a real good place for a sender the drain, for obvious reasons, is set at the very bottom of the water jacket, that might be what the obstruction is.

I one bought a 19 foot fishing boat where the PO had installed 3 compasses on the dash, I mean WTF direction are we really going?

In my Dad's case, decades ago, out to sea unintentionally.

 

Because someone had placed a steel knife next to the compass!