I’ve had an issue with tailcap oring in my FT03. I noticed it being harder and harder to get the tailcap screwed on recently, and tonight it’s impossible.
I use silicone grease out of the same tube I have used for years on my other lights, never had a single problem - but on this oring it seems to be melting and swelling. I cleaned it up and the tissue was black with grease and rubber - it has also swelled quite a bit bigger and is no longer usable. For now I’ve gone back to Vaseline on the spare oring.
Anyone else had issues?
</a
Try silicone electrical contact grease. No problems. I bought a large 4oz (85g) tube at the parts dept of my local Ford dealer. The grease Ford and Chrysler use is actually Nyogel 760G
If one silicone grease is causing deformation, IDK why another wouldn’t do the same. “Like degrades like.” You don’t want to use silicone lube on silicone seals (which it’s entirely possible that oring is). Silicone grease is great for almost every other type of rubber though, and silicone seals are just fine with many synthetic/hydrocarbon lubes.
IDK what that actual material compatibility is for petroleum jelly but IDK if that’s a good idea either. I’ve seen manufacturers warn to not use it for buna/nitrile seals and I think it has issues with other plastics and rubbers. Basically anything sensitive to other petroleum-based products probably won’t like it, and there’s really no way of knowing what the orings are made of.
That lube might be a semi-synthetic. Not saying there aren’t any black silicone o-rings, but the only colors I’ve seen are these.
Good point about the grease! Who knows what other additives, etc. could be breaking them down if it’s not meant for seals.
Same here with seeing those the most by far but black and others colors are definitely available, IIRC McMaster-Carr had mostly black for the silicone options I saw when last buying some. Don’t know why manufacturers would even pick one material over another, but I do know I wish they would list sizes and materials in the manual! :weary:
…or they could just start using FKM or something similar and then we’d barely have to worry lol
Found my FT03 tail cap overly difficult to turn as well. Not impossible but certainly not ideal. Tried silicone. Tried Super-Lube. Using Nyogel now and its doing pretty well.
It is a very complicated question. Some rubbers don’t like mineral-based lubes, others are quite tolerant to any lubrication.
Silicon-based lubes are OK, but you never know what’s inside these aftermarket automotive maintenance tubes.
Thanks for the input guys, like I said I think it must be these oring specific (FT03) as I have quite a few lights and this has never happened before, not even slightly - I checked the manufacturer site and it even recommends it for orings and rubber.
I had a good search on the web, and came across a quite funny discussion on CPF (which showed how ‘rude’ they could be , moderators that is) but at the end of the day there are too many ‘yes’ and ‘no’s’ for any lube lol - no definitive answer overall.
I’ll buy some more orings - to be honest the ‘gap’ for the oring on the light isn’t the best anyway, ideally it would be ever so slightly curved inwards to help retention, but it’s completely flat and really it’s too wide for the oring.
This issue is only with this light’s orings, so I’m fairly sure if I get some more it will be fine.
I noticed a similar situation with D4S / D4SV2 o-rings, except mine had already swelled upon arrival. Either that or they’re the wrong size.
I spent some time looking into this in the past. I used to use a small tub of silicone grease (JETBeam branded) but have switched to Super Lube Synthetic Grease. I don’t know if it’s better / more compatible but seemed to be quite popular and highly praised. I haven’t had any problems with either of them but I like that the Super Lube is thinner and makes threads feel a bit smoother.