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Motorcycle Discussions => British Bikes => Topic started by: Oggers on May 12, 2022, 10:54:01 AM

Title: Sealing petrol taps into the tank
Post by: Oggers on May 12, 2022, 10:54:01 AM
Chaps

Quick Q please

I have now managed to shear my reserve petrol tap on the Viper. I have ordered a new one as below

https://www.groveclassicmotorcycles.co.uk/A26R-Petrol-Tap---Lever-Type---Reserve

Clearly the L/H side 1/4 BSP screws into the tank boss. Any advice as to sealing methods please? The old one simply had a Dowty washer and I am not sure if that is adequate.

 
Title: Re: Sealing petrol taps into the tank
Post by: iansoady on May 12, 2022, 11:17:08 AM
I always use Dowty washers and find they work very well - better than the old fibre ones which these days tend to be far too hard. But make sure you get them with Viton seals.....
Title: Re: Sealing petrol taps into the tank
Post by: Oggers on May 12, 2022, 11:42:36 AM
Ian

Why Viton and not Nitrile? I thought Viton was for high Temp only?
Title: Re: Sealing petrol taps into the tank
Post by: iansoady on May 12, 2022, 02:19:49 PM
It's more resistant to current fuels as I understand it.
Title: Re: Sealing petrol taps into the tank
Post by: Rex on May 12, 2022, 04:24:06 PM
A new "soft" red fibre washer and a couple of turns of PTFE tape. Using the tape also allows perfect tap positioning too.
Title: Re: Sealing petrol taps into the tank
Post by: R on May 12, 2022, 04:46:13 PM
A trace of soap paste wiped onto the threads seals pretty good too.
Regardless of which seals you use ...
Title: Re: Sealing petrol taps into the tank
Post by: Oggers on May 13, 2022, 08:18:16 AM
Just to be clear on fitting the tap

Before fitting, place Dowty washer or fibre washer over the tap end to make flush with the locknut
PTFE tape/soap - whatever onto the exposed portion if the thread
Screw into tank boss - lever facing outwards
Do up locknut

Is this right?
Title: Re: Sealing petrol taps into the tank
Post by: Rex on May 14, 2022, 10:19:25 AM
Sounds good to me, although I like to wind a couple of extra turns where the fibre washer hole is to ensure that the hole is fully sealed too.
Title: Re: Sealing petrol taps into the tank
Post by: iansoady on May 14, 2022, 04:17:57 PM
That's why I prefer dowty washers. Plus as I mentioned it's very difficult to get fibre ones that are not rock-hard.
Title: Re: Sealing petrol taps into the tank
Post by: Oggers on May 16, 2022, 08:16:41 AM
Thanks chaps- I have used Dowty washers and all seems well - so far....

Supplementary question if I may. The kickstart bush appears to be weeping oil. This is the main bush through which the kickstart shaft roatates. Bit of weep which is somewhat annoying. Apart from renewal, is there anything I can do here please?