I have a leak in a high pressure hydraulic circuit at a BSPP male plug fitting. This plug is the type that has a machined recess for the o-ring, and there was a square cross section o-ring there. It looked flatter than it should have, so I replaced it with a round section o-ring from a Dowty seal and it still leaked.
Next I replaced the plug fitting with another type that simply had a large flat sealing surface, and I used a Dowty fitting on it, which leaked, then a plastic washer with a much larger surface area than the Dowty and it leaked too.
Since I've now tried two different fittings and three different types of seals, I'm thinking it's not the fittings that have a problem, but the female port that I'm trying to plug.
I've got some Stat-o-Seals arriving tomorrow, but if those don't hold, my options are narrowing down quickly.
Anyone ever used thread sealer or teflon tape on these fittings? I realise with a BSPP fitting, the threads aren't supposed to do the sealing, the o-ring is, but in my case it's not, so I'm looking at all alternatives.
Next I replaced the plug fitting with another type that simply had a large flat sealing surface, and I used a Dowty fitting on it, which leaked, then a plastic washer with a much larger surface area than the Dowty and it leaked too.
Since I've now tried two different fittings and three different types of seals, I'm thinking it's not the fittings that have a problem, but the female port that I'm trying to plug.
I've got some Stat-o-Seals arriving tomorrow, but if those don't hold, my options are narrowing down quickly.
Anyone ever used thread sealer or teflon tape on these fittings? I realise with a BSPP fitting, the threads aren't supposed to do the sealing, the o-ring is, but in my case it's not, so I'm looking at all alternatives.