Tyre "bead sealing" question.

[Jim Bell]

Need to tap the font of Autoshite knowlede.

 

Its tyre related. Can a tyre leak from the bead or would a very slow, gradual leak always indicate a puncture?

 

I'm buying a (horrible) car with two slow leaks, but the tyres are almost new.

The vendor (my auld man) recons theyre just not sealed at the bead probably.

 

Sound like bullshit? Or plausable?

 

 

[KruJoe]

Highly probable.

Steel rims: rust lets air out.

Alloys: cracked paint allows corrosion under it, air seeps out under that way.

[Jim Bell]

Cheers for the reply Joe.

 

The rims in question are Voxhall alloys, paint seems very good from what I can see by eye.

 

Worth getting them knocked off and re-fitted do you think?

[Sigmund Fraud]

KruJoe is spot on !

 

Most reputable* tyre places should be able to take the tyres off the rims, repair any punctures with their special plug (ooh, err) and re-fit them for under £15. If there's no puncture to repair, they may charge even less.

[KruJoe]

The paint may have been scraped when the last tyres were fitted, or slight curbing will damage it, allowing corrosion under the bead.

Your fitter will know what to do to make it seal, but will probably only wire brush the area and slap on the tyre soap - short term fix.

If possible, get the tyres off, rub any rough area right down to bare metal, and re-paint properly. Or I've done it successfully with silver Hammerite before - looks fine and mostly hidden. Good paint adhesion essential.

HTH.

[alf892]

Alloys need good paint on the wheel (inside the tyre) not just around the bead otherwise they will go down slowly.

[Jim Bell]

Cheers all.

 

Thats all great info.

[Cavcraft]

What we used to do (tyre company I worked for) was to let the tyres down, remove from wheels then put the offending wheel/s on the balancing machine. Goggles on, hold wire brush against inner edges of wheels (where the tyre bead sat) then refit the tyre.

Before inflating we used to dollop loads of bead sealer on, then inflate the tyres to about 55psi, then let down slowly to required 'usual' pressure.

[Black_GT]

3 of my tyres had slow leaks earlier this year - a fitter charged £15 per wheel to wire brush the corrosion and re-seal the wheels - also needed a valve replacing as that had a tiny leak.  Extra bonus: he drove a Triumph Dolomite!  6 months on... no leaks!