How best to seal 1/2 BSP oil fittings?

[R1 Indy]

I've just fitted an oil cooler and accusump to my kitcar.

I used a couple of turns of PTFE tape on all the threaded joins.

Seemed ok on first startup, took it for a test drive noticed a couple of drops. Then drove it quite hard and the hot oil was showering off my chassis :sad:

I'm questing I didn't use enough PTFE tape, but is there something better for sealing the oil lines?

Cheers

[Spitbarnatt]

You need some dowty seals, esentially a washer with a rubber seal in the middle. Most hydraulic companies will have them.

[McWigglebum4th]

Are you sure they are BSP?

As unless it is a BSP taper then it should be a dowty washer or a face to face seal

[R1 Indy]

Most of them are tapered fittings.

I think the main offender is a female to female connecter and T piece that are not tapered, so rely on the threads to seal.
Would a Dowty seal work here? I can't quite picture how they fit.

[McWigglebum4th]

R1 Indy said:

Most of them are tapered fittings.

I think the main offender is a female to female connecter and T piece that are not tapered, so rely on the threads to seal.
Would a Dowty seal work here? I can't quite picture how they fit.

Ah

You should put a tapered male into a straight female or the other way round as it won't seal

Also a BSP taper will screw into a NPT taper but won't seal

Lots of fun coming your way

[littleredrooster]

Threads are a constant helix so they cannot seal by themselves, especially under pressure.

You will need to engineer a different solution which places a proper seal in the right place to stop the oil from entering the thread.

[Alfreda]

Use oil leaking seals, which is a washer & comes with a rubber seal in the middle. Most of the sealing companies will have them.

[Republik1980]

Dowty washers / bonded seals rely on being crushed between two adjacent faces to seal. To use them in your application you'll need a shoulder on the male section that butts up against the female section when tightened.

You shouldn't have to rely on PTFE tape to seal if the thing's been engineered properly.

[paulshears]

If your hose's have male ends they "should" be BSPT (tapered) thread ... PTFE tape should be fine on them

If your hose's have female ends they "should" be swivel female, BSP (parallel) thread
with a cone seat ... these seal on the seat, do not used PTFE tape or thread sealent on these

If any of your parts are made in the USA they won't be BSP/BSPT they will be NPT

On 1/2" BSPT & NPT are the same threads per inch, but the degree of taper is different ... If you really have to you can put an 1/2"NPT male into a 1/2"BSPT female

If by any chance your near Hull (East Riding of Yorkshire) come & see me at Arma Hydraulic Engineering

Paul