The caps on my brake fluid reservoirs are pretty much used up - the threaded aluminum are crimped into the plastic cap/float assembly, and those crimps have come un-done, and small pieces have fatigued and broken off. So, I need new caps.
I have round bottles, if that makes a difference. Not sure if round is correct or not, but I’m not fussy about originality.
What is the quality of replacement caps available these days? I know the replacement bottles have a long history of poor quality. Are the caps sold by SNG any good?
Yes the Sovy repro caps are good quality and I have never had an issue with them (unlike the bottles!). The bottles changed from round to square in July 1962 but the repro caps will fit either. Get the black ones as they would be original style for the car. Later caps were white but they are mechanically the same.
I bought the square reservoir bottle many, many years ago but am just getting ready to install them. The plastic tops are red. Every one that I see on line are clear. Which is correct? '64 3.8 OTS
The answer is most likely in this summary posted by Heuer just above your post - the red caps are mentioned in it. I have never seen clear caps, white yes, but not clear.
Prototype and pre-production cars - either Sovy unmarked black cap or Lockheed NIVOCODE
First ~500 cars up to August 1961 - Lockheed NIVOCODE sensors as illustrated in the August 1961 J.30 SPC
August 1961 to July 1962 - black cap Sovy sensors with 'Sovy and ‘Made in England’ imprint
July 1962 to March 1963 - white cap Sovy sensors with 'Sovy and ‘Made in England’ and maybe ‘Patent applied for’ imprint
April 1963 onwards - white cap Sovy sensors with Patent numbers and push fit waterproof caps
January 1964 onwards - protective rubber caps, which could be retrofitted to earlier cars.
Red caps were fitted to some Lotus models but were after market replacements on the E-Type. Simple rule - round bottles are black cap, square bottles are white cap.
Indeed, and that’s the only way I ever saw them. The black ones on the early cars, and the kind of milky white ones on the later cars with the rubber covers.