Author Topic: Petrol tap to avoid  (Read 13844 times)

Offline jhg1958

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Petrol tap to avoid
« on: 14.09. 2025 17:26 »
Finally got around to changing the reserve petrol tap a job I have been putting off for ages. I bought a replacement some time ago. 

I bought the tap with the right thread but little thought about other aspects.

When I fitted it I noticed the tap had no shoulder on it. I thought I could use ptfe tape to seal the threads but each time I found the threads weeping petrol.

Yesterday I noticed tthe ptfe tape had been stripped off so not that surprising that it was not sealing.  This time I put an O ring on and a liberal amount of Hymolar blue and at last success.

I wish remembered where I bought it or when.

John


1961 Golden Flash S/Arm

Offline Rex

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Re: Petrol tap to avoid
« Reply #1 on: 14.09. 2025 20:05 »
Odd that it has no locknut as you need that to lock it in the right position. Some don't seem to mind the plunger pointing in odd awkward directions, but I like mine to be a straight outwards pull.

Online berger

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Re: Petrol tap to avoid
« Reply #2 on: 14.09. 2025 22:13 »
i went to the pub so i know nothing but i bet it's chinesium and came with a union jack on the packaging  *beer*

Online orabanda

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Re: Petrol tap to avoid
« Reply #3 on: 15.09. 2025 00:33 »
Re sealing the thread:
Wrap the thread tape on in the same direction that the tap screws in; this will ensure it doesn't peal off as the tap is fitted.

Better still, use 569 loktite.
Cheers
Richard

Online Brian

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Re: Petrol tap to avoid
« Reply #4 on: 15.09. 2025 07:04 »
Firstly they are not original and guess what, I dont care ! I use Paoli (BAP) taps on all my bikes, they dont leak, are not effected by modern fuel and are easy to turn on and off. I have a Moto Guzzi that is 42 years old with them fitted and they still work like new. Dont bother with thread tape, thats designed for water, use 569 (hydraulic sealant) loctite as Richard has suggested.

Offline jhg1958

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Re: Petrol tap to avoid
« Reply #5 on: 15.09. 2025 16:06 »
Well they are brass (probably India) not chineesum.   See the picture of chineesium one that I bought some time ago.

I wrapped the PTFE tape the right way around so that was not the problem. Fortunately the Hymolar is working well.

Loctight 569 is not readily available in the UK. The price of is astronomical.

My main tap is a 1/4 turn flat lever from SJ Engineering. The problem was it was 1/4 BSP so I am a little concerned about flow rates. Why did BSA go for such a big thread?

John
1961 Golden Flash S/Arm

Offline Rex

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Re: Petrol tap to avoid
« Reply #6 on: 15.09. 2025 16:31 »
Who knows, but it's been working for 60+ years so I wouldn't worry too much... ;)

Offline sean

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Re: Petrol tap to avoid
« Reply #7 on: 15.09. 2025 20:41 »
I bought a set from British Cycle supply they were from India one was ok the other one leaked so bad I threw it way the threads were very loose and it would be too  expensive to return .
the sales person did ask me if a set from India would be ok as they were out of stock of the good ones and he said they have had no problems with the  Indian version...... probably the ones that had a leak got tossed like mine .

Offline bl**dydrivers

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Re: Petrol tap to avoid
« Reply #8 on: 16.09. 2025 02:31 »
Since we’re on the subject of taps

Are they suppose to have a lock nut to adjust the direction of the pull?
Because I’m pretty picky like that too!

I found a pair of NOS Ewarts taps many years ago, have been saving them for when the tank gets restored and going to replace the cork seals with new rubber o-rings

Online groily

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Re: Petrol tap to avoid
« Reply #9 on: 16.09. 2025 07:01 »
Since we’re on the subject of taps

Are they suppose to have a lock nut to adjust the direction of the pull?
Because I’m pretty picky like that too!

I found a pair of NOS Ewarts taps many years ago, have been saving them for when the tank gets restored and going to replace the cork seals with new rubber o-rings

There seem to be locknuts on the lever types, but I haven't seen them on the stock 1/8 BSP Ewarts ones. Tend to have to use washers (fibre, dowty, whatever) to get them pointing where it's comfortable.
Never tried O rings in lieu of corks, have to say - but when the darn things start leaking I regularly go to cheapo plumbing valves with some mods, which don't leak. (Sometimes I'm lucky and successfully recycle old ones, of which I seem to have a stupid number, some shown in the pic. Occasionally, I'll shell out for new decent quality ones if feeling flush.)
A constant source of joy. Not.
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Offline Rex

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Re: Petrol tap to avoid
« Reply #10 on: 16.09. 2025 09:51 »
I bought a packet of new corks off Ebay. Literally 30 seconds is all it takes to have a fully-operational tap.
I like BAP taps if I'm buying new though. No Chinesium crap...I've suffered that too many times after buying a bike.

Online chaterlea25

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Re: Petrol tap to avoid
« Reply #11 on: 16.09. 2025 12:07 »
Hi All,
I tried the O ring solution, it was a failure in that the fuel still flowed when in the off position . It was also incredibly stiff *ex*

On several BSA models the 3/8 bsp reducer sleeve has a built in filter on the top. These have a shoulder to accept a fibre washer between it and the tank.

John
1961 Super Rocket
1963 RGS (ongoing)

Online JulianS

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Re: Petrol tap to avoid
« Reply #12 on: 16.09. 2025 13:49 »
I too had a failure with the o ring conversion, the rings seemed to get torn where they cross the drilling in the tap. Also tried the Draganfly conversion which replaced the cork seal with a neoprene one. This sealed OK but it was extremely difficult to operate the tap.

Offline scotty

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Re: Petrol tap to avoid
« Reply #13 on: 16.09. 2025 14:04 »
Not for the rivet counters but……
had these billet taps with petro tape on the threads for years with no leak dramas




Scotty

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Offline jhg1958

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Re: Petrol tap to avoid
« Reply #14 on: 20.09. 2025 16:52 »
Update

I gave up.

Hylomar failed to keep the petrol from weeping out of the thread for very long, I assume vibrations took its toll. I gave up with this brass tap and bought the same as I have on the LHS SJ engineering on Ebay.  As they also supply the adapter it make life easy and the single 1/4" tap seems to be ok for most of my riding. 

John
1961 Golden Flash S/Arm