Foot pump maintenance (car tyres)

[Another John]

We have an old banger for running around in, and I need to use my foot pump more than I'd like on its rather old and rusty wheels.

Lately my pump *seems* (could be wrong) to have become less effective, i.e. I seem to need more pumps per PSI injected.

Is there any kind of maintenance I could do on the pump? The cylinder is welded closed, but I wondered what might happen if I (for example) sprayed WD40 into it via the air intakes. For example would it revitalise the valve in there? Obviously I could try it, but maybe someone here has tried it before, and can advise Yes or No!

Cheers J.

[newshound]

In the good old days these were very robustly made and could be maintained. The main seal was greased leather. IME modern pumps are more flimsy and it is usually the hose which gives out first, typically leaking at the crimped joints.

If you are *sure* the hose is OK (leak test with soapy water spray?) it could be the main piston seal. WD40 might let you do a quick check as you describe but someone will be along in a minute telling you that mineral oils are bad for rubber tyres. Silicone oil (as used for lubricating plumbing fittings) would be OK, but not cheap.

You might find that one of those little electric pumps which you can sometimes pick up for a fiver with a tank of petrol will meet your needs.

[Thomas Prufer]

Mineral oils are bad for rubber.

Now that that part is done: Grease or petroleum jelly/vaseline on the leather.That wil stay there, the WD-40 will run off (and also evaporate eventually). Open the pump, pull out the leather cup thing, dredge the gob of grease out of the cup and spread it around the rim of the leather, reinstall the leather with a twisting motion, and you're done (except for getting dirty grease of your fingers and the new trousers you wore by mistake).

Thomas Prufer

[newshound]

Except that as the OP pointed out, the cylinder is welded closed.

What a WD40 test tells you is whether the pump might be fixable (e.g. by pouring in some expensive silicone) or whether it is ready for the scrap-heap. The amount of mineral oil in a few sprays of WD40 is not going to bother a tyre.

[Alan Braggins]

And as someone else pointed out, seals _used to be_ greased leather.

On the other hand, if the problem is a rubber O-ring inside the pump that is already perishing, a few sprays of WD-40 probably won't bother that either, or they might push it over the edge.

[Bob H]

I bought one of those pumps which you plug into the cigarette lighter socket, and its great, with no effort required to pump up the tyres.

[Dave Liquorice]

So did I when they first appeared on the market. Didn't take kindly to the pumping up Discovery tyres, from 25 ish to 30 psi, exceeded the duty cycle, over heated and died. 'twas only about a 2 cc cylinder... It would have been alright with topping up ordinary sized car tyres.

Now have a somewhat larger and fan cooled one more designed for the truck market. B-)

[Huge]

Ahh. I have a Discovery. And a Draper tyre inflator. But given the time it took to pump up a trailer tyre, it wouldn't surprise me at all if pumping up a Disco tyre didn't kill it.

Always assuming I could get the spare out from underneath. (Disco III, innit.)

That sounds like quite a good idea. What make is it?

[Theo Markettos]

They're noisy and slow - take about 3-5 mins per tyre. They're also full of plastic gears which are quite easy to strip.

Theo

[Mike Barnes]

I have a pair of earplugs stored with mine. And there always things to do in the garage with those minutes. Actually only 1-2 minutes for the usual top-up.

[meow2222]

WD40 is quite the wrong thing. A drop or 2 of oil into the pump often fixes it. Very little of it ever gets out into the tyre, and driving over engine oil doesnt do a tyre any significant harm.

NT

[Dave Liquorice]

Niether of mine have been *that* noisy.

[Dave Liquorice]

Sealy MAC2300

pr oductid=6960#tabs-1

But I don't think I paid that much for it. I didn't, Classic Car World, Mar 2008, £46.28 all in.

[newshound]

I have just got one of these

for my Renault Master horsebox, which lives on a site without mains power and it is excellent. (55/65 psi 225-65R16 tyres).

[Chris J Dixon]

I guess you don't run that off the lighter socket? ;-)

Chris

[Dave Liquorice]

mains

It doesn't come with a lighter plug only crock clips... With a max pull of 30 A that isn't surprisng most lighter sockets are fused at

10 A.

The Sealy does run froma lighter socket, far more convient.

[newshound]

Correct, but I have leisure batteries kicking around the yard, and also the battery in the Master is conveniently in the middle of the cab floor and the flex + hose will reach each wheel.

I havn't checked the current draw, I think they said it was 15A typical

30A max.

[Adrian]

Probably not going to work terribly well on a diesel Disco or van, either...

[Gazz]

Nor single cylinder motorbikes for some reason :)

[Theo Markettos]

If it's used on the carb engines it was designed for, won't it be pumping fuel/air mix into the tyre?

"a quick, easy way to inflate your tires, air mattresses, rafts, etc"

Smoking in bed could cause fireworks...

Theo