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Technical (Descriptive Topic Titles - Stay on Topic) => Amal, Carburation, Fuel => Topic started by: NickSR on 09.08. 2009 22:09

Title: Petrol Tap - Changing the Cork
Post by: NickSR on 09.08. 2009 22:09
Hi Everyone
Any tips in changing the push / pull tap cork on my 1962 Super Rocket ( standard tap).

Thanks

Nick
Nottingham
England
Title: Re: Petrol Tap - Changing the Cork
Post by: groily on 09.08. 2009 22:30
facetious advice I know, but I'd bin it and get a Gas Tap from a plumber's merchant, which you can fit and forget, with or without an adaptor from 1/8 to 1/4BSP (can't remember what the standard fitting is) and a bit of fettling to make a filter. It won't leak. Messing with corks and grub screws and plungers and all that is a PITA. And there's no guarantee a 'proper' re-fettled tap will work even if you offer it up to the Moon on the right night of the month, soak it in special unguents and talk to the fairies. Lousy horrible unreliable things and I've never understood how we've allowed our nice motorcyclists' nature to be so abused . . .

But don't worry, someone sensible will be more helpful if you really want to persevere with the original one!
Title: Re: Petrol Tap - Changing the Cork
Post by: a10 gf on 09.08. 2009 22:36
Quote
Lousy horrible unreliable things
yes

(edit: had cork residue ending up in carb, blocking jets, and messing up the float. They were new, unused, but cork fell apart after 3 days of use)
Title: Re: Petrol Tap - Changing the Cork
Post by: maxwelton on 10.08. 2009 02:02
I am about to try a couple of these kits:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=350229350899

They should be here early this week and I hope to fit them by week's end. I'll let you know if they actually work, seems like s decently engineered solution.
Title: Re: Petrol Tap - Changing the Cork
Post by: LJ. on 10.08. 2009 09:40
Quote
But don't worry, someone sensible will be more helpful if you really want to persevere with the original one!

Quote
Quote
Lousy horrible unreliable things
yes

Nope!  :D

Okay... Lemme see if I can fit the sensible bit.

Gags or TMS as your a Nottingham chap and get some new corks, take a good look at them and pick out a couple that have no cork veins in them. Now as your going to need to work with an empty petrol tank. Make sure that your tank is spotlessy clean, petseal it if there is any fine rust on the inside. That fine rust is the perfect abrasive that wears away your corks!

If you do go the petseal route then you'll need to remove the taps so check the wire gauze filters and prepare with new fibre washers and ptfe tape round the threads.

Putting the corks in, You need to boil the corks so that they are well soaked, push them gently in without squeezing all the water out, that water helps in keeping the corks spongy. Fill tank with petrol as soon after fitting the corks so that they dont start to dry out. Its important to keep the corks surrounded with petrol to prevent the water in them drying out. With the corks in a nice clean chamber and water wet they'll last a long time. Dont be tempted to grease the corks in anyway they need to be clean and water wet. Ensuring all this there is no reason why they should give any more problems.

Edit... Roger after posting this I looked at the Ebay link you posted. Those taps do look good but again as with the corks, the tank would need to be clean with no abrasive material swirling around inside, the rubbers would likely wear away like the corks. Still think I prefere the original aspects though.  *roll*
Title: Re: Petrol Tap - Changing the Cork
Post by: Rusty nuts on 10.08. 2009 09:57
I am about to try a couple of these kits:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=350229350899

They should be here early this week and I hope to fit them by week's end. I'll let you know if they actually work, seems like s decently engineered solution.

Looks interesting.
My bodge is as follows:
Buy new cork about 45p, slice cork lengthways with scalpel blade, ease on, apply evo-stick to inside edges of cut,
wrap up really tight & leave for 24hrs, soak in water, olive oil  or whatever takes your fancy for another 24hrs, fit & forget.

Cheap & nasty fix I know, but this tap is bone dry, unlike the repro brassform I bought that leaks all over the place.
Title: Re: Petrol Tap - Changing the Cork
Post by: LJ. on 10.08. 2009 10:03
Quote
My bodge is as follows:
Buy new cork about 45p, slice cork lengthways with scalpel blade, ease on, apply evo-stick to inside edges of cut,
wrap up really tight & leave for 24hrs, soak in water, olive oil  or whatever takes your fancy for another 24hrs, fit & forget.

FX: (Sound of) Deep Grroooaann!  *doh* *doh*
Title: Re: Petrol Tap - Changing the Cork
Post by: bsa-bill on 10.08. 2009 14:57
Slice !!!
with a good pair of pliers ( not the ones you tried to remove the rear wheel spinlde nut with) grap the button of the pin that holds the cork in and pull it out, remove washer and cork, fit new cork ( pre soaked as stated ) fit washer, push pin back in,
Did this five years ago and they have held petrol ever since, I have another set soaking in a jar of petrol as replacements, even if I needed them now 80 pence every five years is fair enough.
I had to replace the rubber seals in my sons Honda when it was about five years old ( cost more than 80 P tho )

All the best - Bill
Title: Re: Petrol Tap - Changing the Cork
Post by: a10 gf on 10.08. 2009 18:50
I'd rather fit the bike with wheelbearings made of cork and mothballs than cork taps, but acknowledge others have had good results with them. Looking forward to Roger's experience.
Title: Re: Petrol Tap - Changing the Cork
Post by: G/F DAVE on 10.08. 2009 19:15
Must admit I have Ewarts taps fitted to all my bikes, Corks can replaced easily and are cheap! Do as Bill suggests and no problem but make sure you peen the brass centre when you refit cork to plunger, I had one pull thru after a night in the pub time to go home and no fuel flow had to strip plunger from tap and pull out brass centre with a pair of pliers.You need a good supply of spares to make up a good tap that doesnt leak and a degree of patience. Best bet if you cant be bothered is to fit a gas tap problem sorted *smile* Dave
Title: Re: Petrol Tap - Changing the Cork
Post by: rocket man on 10.08. 2009 20:51
i know the best place for a cork in a bottle ove wine
just think if your taps leak and it ends up on your mag
it will make a nice fire then you can open your bottle ove wine
and drown your sorrows
Title: Re: Petrol Tap - Changing the Cork
Post by: Triton Thrasher on 10.08. 2009 21:53
facetious advice I know, but I'd bin it and get a Gas Tap from a plumber's merchant, which you can fit and forget, with or without an adaptor from 1/8 to 1/4BSP (can't remember what the standard fitting is) and a bit of fettling to make a filter.

As a fuel tap, unbeatable.

I use an inline filter.
Title: Re: Petrol Tap - Changing the Cork
Post by: maxwelton on 10.08. 2009 23:43
it will make a nice fire then you can open your bottle ove wine

I caught my bike on fire just after it was all back together for the first time...not a fuel tap, but over-zealous tickling squirted some on one of the mag leads. My fire extinguisher was on the other side of my now locked garage door. Fun times. Fortunately not a lot of damage, mostly pride.
Title: Re: Petrol Tap - Changing the Cork
Post by: mike667 on 11.08. 2009 21:58
I am about to try a couple of these kits:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=350229350899

They should be here early this week and I hope to fit them by week's end. I'll let you know if they actually work, seems like s decently engineered solution.

i fitted this kit in both my taps on my A10 about 2 months ago -  and while it isn't buttery smooth sliding action to pull them out they are well made units and i suspect will last quite a long time - only draw back is a bit pricey....
Title: Re: Petrol Tap - Changing the Cork
Post by: maxwelton on 17.08. 2009 20:15
The kits turned out to be, for me, very expensive drill bits. They were unusable on my machine, as the plungers simply didn't fit into my taps. Of course, being an optimist, I neglected to test fit the new piece before taking apart my old one.  *eek* New taps it is, for me.
Title: Re: Petrol Tap - Changing the Cork
Post by: beezalex on 19.08. 2009 16:35
i fitted this kit in both my taps on my A10 about 2 months ago -  and while it isn't buttery smooth sliding action to pull them out they are well made units and i suspect will last quite a long time - only draw back is a bit pricey....

Try lubricating the O-rings with bar soap.  They should go much smoother.
Title: Re: Petrol Tap - Changing the Cork
Post by: maxwelton on 21.08. 2009 00:03
Just put my new taps in, with the large-to-small adapters that were necessary for the replacement taps. Smooth action and so far no leaks. Now to see if I can find a welding supply joint here on the island so I can get some crimp fittings to make up new fuel hoses...
Title: Re: Petrol Tap - Changing the Cork
Post by: NickSR on 24.08. 2009 21:33
Hi Everyone

Sorry for not replying sooner IT problems, many thanks for all the advice its been a great help.

Regards
Nick
Notts
England
Title: Re: Petrol Tap - Changing the Cork
Post by: bsa-bill on 21.03. 2015 16:13
Had to replace the corks last week the tank having sat empty  for some the corks had dried out, the spares I had soaking were the originals out of the bike and had not got better so sent for some new corks which arrived today, pulled the tank into the middle of my bench to change the plungers (spare one now equipped with the new cork) ha only to find the ones in there had now swelled and worked fine, so there you go got spare corks at least.

Now then anyone know what size and thread the little set screws are that hold the plunger in or if available anywhere, the ones I have are odd, I think one might be original but the other is definitely not.

Just tidying things up a bit while I'm onit
Title: Re: Petrol Tap - Changing the Cork
Post by: trevinoz on 21.03. 2015 20:56
From memory, Bill, those screws are 5BA but you could get away with 1/8"BSW.
Title: Re: Petrol Tap - Changing the Cork
Post by: morris on 21.03. 2015 21:05
Just had a look on mine. They're definitely 4 ba.
Title: Re: Petrol Tap - Changing the Cork
Post by: bsa-bill on 21.03. 2015 22:14
Thanks lads, I'll get me some
Title: Re: Petrol Tap - Changing the Cork
Post by: trevinoz on 22.03. 2015 00:05
Disregard the my previous post, Bill, Morris is correct.
I made some many years ago. They have a flat head and a reduced diameter to fit the plunger.
Title: Re: Petrol Tap - Changing the Cork
Post by: bsa-bill on 22.03. 2015 08:47
no problem Trevor I ordered a few of each as little screws are always handy in the shed, plus when I buy them I know what they are and label the partition in the box, otherwise they all become "Misc" *eek*