Tyre problem- advice needed

[jozg44]

I have a mysterious problem with one of my tyres (or should that be tires ?) on the SIII.

Came out one morning to find my rear-left tyre completely flat- no air at all.
I jacked up the Land Rover (which took ages because I was using the standard LR screw-jack and it takes most of the jack travel just to take up the articulation in the springs). I got the wheel off, whipped on a spare and took the flat tyre to the local tyre shop.

Went back later in the day, and the man there said he could find nothing wrong. He had the inner tube inflated, and poured soapy water over it- no leaks. The same with the tyre, the valve etc. etc. The wheel was in good condition, with no damage to edges and nothing to break the bead of the tyre.

Took it back and put it back on the Landy (my spare is a Firestone M/T, which I do not enjoy driving on if avoidable).

On Sunday I was trundling along the motorway, and suddenly the Landy slowed down and I heard the ominous 'dudda-dudda-dudda-dudda' noise of a flat tyre. Same tyre- suddenly lost all its air. Did a quick wheel change on the hard shoulder, in the dark (not fun!).

So- any thoughts as to why a tyre with no apparent damage to inner tube, tyre or wheel would suddenly lose all its air?

It's a 7.50x16 General All-Grip, a fairly non-aggresive all-terrain.

EDIT TO SAY: Thanks, whoever moved this into the CORRECT forum. Just didn't see the big 'Wheels and Tires' notice

Jack

[Bogatyr]

jzog44,
You said your rims appeared good, but have you checked on the inside? I'm wondering if there's a rusty spot in there somewhere...If a shop around here puts a tube in tire, they usually insist on putting a flap or liner over the rim just so the tube doesn't chafe...

I suppose you could try mounting that tube and tire on another rim to try and isolate the problem to either the rim or tube/tire combo...

Bogatyr

[Disco]

My guess it's a faulty valve, which although does not leak when the vehicle is stationary, does so when it's subjected to rotational forces. Changing the valve should solve the problem.

[DiscoPilot]

Originally Posted by Disco

My guess it's a faulty valve, which although does not leak when the vehicle is stationary, does so when it's subjected to rotational forces. Changing the valve should solve the problem.

I second that they dry rot and crack near the wheel and the rotation of the wheel makes them bend outwards and stretches open the cracks. go to the car and push the valve stem out towards the outside of the wheel, you'll probably hear air rush out.