For the last week or two I've found the front nearside tyre deflated on several occasions. It's not always at home, ruling out a kid's prank (I hope). The tyre appears undamaged so I suspect the valve.
Over Christmas I will boldly swap the valve as quickly as I can, and have one of the boys time me. The tyre will start off with 2.5 bar in it and no valve cap. I will be working with standard safety clothing (overalls, woolly hat and carpet slippers).
To claim your virtual mince pie, suggest how long it will take me and how much pressure will remain in the tyre when I've screwed the new valve home.
Good luck and Happy Christmas to you all.
PS There will be no tacky Youtube video of this; you'll just have to trust me.
Last edited by: hawkeye on Sat 24 Dec 11 at 11:48
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Assuming you put your finger over for the short time whilst lining the new valve up and you have a valve key cap you can spin proper, not one of those horrid square thingies, 8 seconds hissing 22 seconds total, no funny money here you will lose 7lbs pressure, if you have the horrid valve key with never needed rethreading tools too, 18 seconds hissing, 25 seconds total and 13lbs loss.
Have you tried the good old fashioned spit test, or indeed some soapy water round the base of the valve and a waggle, if no leak take wheel off and submerge totally in clean water.
Last edited by: gordonbennet on Sat 24 Dec 11 at 12:25
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>> the base of the valve and a waggle, if no leak take wheel off and
>> submerge totally in clean water.
Yeah, bung the wheel and tyre in the bath, the wife wont mind....
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"Yeah, bung the wheel and tyre in the bath, the wife wont mind...."
Unless she's already in the bath...
Swapping valves sounds like great potential for using many varied long forgotten oaths.
Have you tried a metal valve cap first - with the rubber seal inside, they should act as a secondary seal, so you can see if it really is the valve core?
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>>they should act as a secondary seal, <<<
I maybe mistaken, but I believe that in years gone by Schrader only would guarantee the pressure seal of the cap, not the 'insert valve.
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I think Sod's law will intervene and slow you down - So 30 seconds and no pressure left.
But for your sake I hope I'm wrong.
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Before you flatten completely make sure that you can find a decent working airline!
if you end up with a coin in the slot machine, it wiill probably run out of air and keep swallowing coins.
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The valve will slip through your fingers, fly through the air, and you will lose it - and all the pressure.
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>> The valve will slip through your fingers, fly through the air, and you will lose
>> it - and all the pressure.
Thats the reason those old fashioned valve caps with the valve key on top are worth keeing hold of, small enough that they fit nicely in your fingers with the valve nested securely in the keyway still within your fingers unable to escape.
Pro's use a purpose made rubber handled screwdriver sized version of the above.
The well known brands of valve key made in a cross shape with outer and inner thread cutters opposite each other are too big and clumsy, not what you need when the pressure is trying to blow the valve out as you try to get the thing in and get it threaded and you need two hands, try it with a truck valve with 125psi trying to get out...valve lands about 20 ft away..;)
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I'd check whether it really is the valve first.
1) Check that the valve is screwed in tightly (unscrew a bit then re-tighten)
2) Spit round the base of the rubber neck where it seals in the wheel and waggle it, looking for bubbles
3) Spit into the end of the valve and look for bubbles
4) Press the valve in for half a second with a matchstick and let it go with a snap
5) Repeat test (3)
6) Fit new metal valve cap
7) Retire inside and eat the mincepie yourself
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>> I'd check whether it really is the valve first.
>>
Yes I've done the spit test and fancied I could see it blowing a bubble. Then the 25mph wind took it and smeared it on the tyre wall.
The valve cap is u/s owing to ahem overtightening.
I'm committed now so I'll post what happens and maybe give you all a laugh.
PS Mrs H unimpressed with the idea of sharing the bath with wheel and tyre. Even with the promise of bubble bath.
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>> PS Mrs H unimpressed with the idea of sharing the bath with wheel and tyre.
>> Even with the promise of bubble bath.
>>
Oh well no pic to look forward too :-)
I think a DIY tyre bath is a lot easier to construct these days.
Four wheelie bins on their sides lashed together in a square. A a tarp anchored down with house bricks and dangled inside the square. Add water and dunk the wheel.
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4 wheelie bins?
You must live in my borough, the Royal Borough of Recyling-gon-mad
Last edited by: Zero on Sat 24 Dec 11 at 22:59
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Or mine. We've got 4. The old(er) green one is twice the size of the others mind.
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Well it's results time but before I spill the beans I'm offering a virtual raspberry to Crocks and Iffy for their total lack of confidence in the process.
Yes I have got a horrid tool that does everything but for this exercise I added 2 valve extensions that came off an old c@rav@n so I could spin the valve in. Owing to my cack-handedness and the distraction of our wind-borne wheelie bin trundling past at 5mph I can't find the original valve core that I suspected of leakage.
39 seconds in total including a lot of thumb pressure retention, tyre pressure 2.05 bar. In old money (for GB) that's 7psi pressure loss or 0.45 bar.
So that makes GB the winner in my book. Appeals will be considered carefully while the remaining stock of prize mince pies are despatched by me.
GB feast your eyes on your tasty treat and I hope it's survived its short virtual journey;
www.mincepieclub.co.uk/UserFiles/File/open_crumbling_mince_pie.jpg
Thank you for your contributions.
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Thanks for that pie H, would have been nice if a large dollop of brandy cream had been oozing from those luscious innards, none the less appreciated.
I'll warm it gently on the Scania exhaust manifold, apply a generous helping of the aforesaid and have that for lunch tomorrow with a nifter from me hip flask for medicinal purposes to fight the winter chill..;)
That horrid tool you refer to should fitted to the business end of a decent catapult and fired as far as possible when next you are out.
Last edited by: gordonbennet on Mon 26 Dec 11 at 22:05
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£1.95 for a brand new rubber valve fitting at fast fit place let them fit a new rubber valve for your peace of mind that the seal to wheel is clean as these also leak.
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Citroen C8 MPV - Tyre valve swap challenge Xmas competition - Zero
