My Oil Pressure/Water Temp setup

[Chris-St Louis]

Ah, you're talking temp... Both Ford and LR use Variable senders. I was talking the Oil Pressure gauge on Ford products.

 

[robertf]

Wrong. They are parallel pipe fittings and every fitting supplier worth their pipe dope has adapter fittings to go from BPP to NPT. The size is 1/8" BPPM.

wrong, they are taper.

 

[mkronmal]

wrong, they are taper.

Robert,

If they are taper (and I don't have one to really know), why do they have a sealing washer? I thought that BSPP needed a washer to seal, while BSPT did not. I really wish someone had a spare sender to measure and post a side view of the threads!

BTW - The temp sender in the water elbow is M22x1.5 in case anyone was wondering. These damn engines have NPTF, Metric, and BSPP or BSPT fittings!

 

[byronAU]

These damn engines have NPTF, Metric, and BSPP or BSPT fittings!

That's nothing....early RRC's [to mid 80's] had the front mudguards bolted on with BSW and SAE bolts front and back or vice versa- can't remember now.......I think they must use whatever boxes of parts, whatever standard is close by at the time!

 

[mkronmal]

Found this pic of the STC4104 sender. Looks parrallel to me.

Also, found the following on another Landy site "All Landrover / RR / Disco oil pressure switches should be ? unf ???? early SD1 and other V8 applications were 1/8 NPT & 1/8 BSP" :banghead:

 

[robertf]

I can't explain the sealing washer but I've got a sending unit and a pair of calipers in front of me right now and I can measure a taper. It does look parallel to the naked eye.

I also purchased some of the swagelock parallel adapters and they do not work, the threads are too tight one one end and too loose on the other.

sealing washer could be a fix due to improper tapping depth. tapered threads are a bitch to get machined correctly. there is a very small sweet spot that allows proper depth and sealing tightness.

 

[jimjet]

When i did the switch it came from L.R. with a copper crush gasket and a rubber O-ring.
The threads were /are definately straight at least on my 98.

I used the rubber o-ring ,because, i did not want to over torque the sender possibly stripping the threads in an alluminum housing.

The block has/had a machined surface for the o-ring or crush washer.

It was a straight thread.

Jim

 

[mkronmal]

Robert,

What part number is your sender? What size is the threaded end? Can you post a pic of the sender by any chance?

Thanks

 

[mkronmal]

Received a sender today.

The answer is 1/2 UNF! At least for the STC4104K. The thread pitch is 20 and the major diameter is 12.7mm.

Now, since a 5/16 ORB (O-ring Boss) has a 1/2-20 thead, same as 1/2 UNF, I'm thinking that's what Jim is using.

Frack, what a pain!

 

[robertf]

there is no part # on my sending unit, but it looks a little different than the one in the picture.

must be different for distributorless timing covers.

 

[mkronmal]

Robert,

I suspect you have the wrong sensor installed. You likely have a BSPT or NPT sender that is still sealing. Does it have a crush washer or o ring?

STC4104K supersceeded AMR2092 and is spec'd for:

Range Rover Classic | '87 - '95
Discovery I | '94 - '99 | to VIN XA231750
Discovery Series II | '99 | to VIN XA231750
Range Rover 4.0 | '95 - '99 | TO vin XA231750
Range Rover 4.6 | '95 - '99 | TO VIN XA231750
Defender 90 | '94 - '97
Defender 110 | '93