Classic cars forum & vehicle restoration.

[peppiB]

One of the alloy wheels on my Merc is leaking air so badly I have to inflate the tyre every day. Getting a sensibly priced replacement (tyre size 205 x 65 x 15) is proving difficult, however rims taking 195 x 65 x 15 are relatively plentiful and cheap!! What would be the effect of using these undersize wheels (full set, not just one), and would my perfectly good 205 tyres fit onto these rims?

[peter scott]

How about trying one of those rescue kits that skirt sealant into the tyre?
Another thought: I had an annoying slow on my modern that turned out to be a silly little label that had been left on the bead of the tyre.

Peter
_________________
https://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon

[peppiB]

Thanks Peter - tyre place advised against using a sealant - they said it would ruin an otherwise good tyre. The rim is starting to disintegrate on the inner rim so the tyre just isn't sealing correctly. Being alloys, I am told that an inner tube wouldn't be appropriate as it would just slip and shear off the valve.

[victor 101]

Have you thought about U-Pull-It, they do 15" alloys for £15 & tyres for £8, at that price it might be worth a trip if they have your size. http://www.u-pull-it.co.uk/home.html

[PAUL BEAUMONT]

When you say disintegration do you just mean bead corrosion or are you looking at something potentially much more catastrophic?

I had the former problem with my last car and took it to Metal Magic in Barnsley.
They took the wheels off the car, stripped the tyres, shotbasted powder coated and sealed the wheels then rebuilt and balanced the wheels and returned the car next day with change out of £300

Never had another soft tyre afterwards.

There is probably someone near you doing something similar

Paul

[peppiB]

Paul,
It is bead corrosion on 1 wheel (plus the rim I have on the spare) The whole car is currently worth more as scrap than as a car so £300 is beyond economic repair, sadly, although recently 2 of these 500 SEL models have made it to 4 figures, but that is unusual.

Tried the UPull site but they do not have a suitable donor vehicle

[47p2]

U-Pull-It have a massive stock of wheels, if they aren't too far away from you it might be worth popping in for a look to see if they have any suitable wheels in stock
_________________
ROVER
One of Britain's Fine Cars

[Kelsham]

Why not have the tyre removed and clean up the rim with a wire brush in a drill, then use an etching primer and finish with a topcoat from a spray can. I did this on my XJS five years ago. Still holding air.
regards Kels.

[Bengt Axel]

[SV8Predator]

[peppiB]

[Dirty Habit]

This is the place for all your questions about wheels and tyres.

http://www.carbibles.com/tyre_bible.html
_________________
1964 International Harvester

[HMK]

Had this problem with old alloys many times- & it's an easy fix.....but first..

SV8Predator is 100% correct in what he says....you should never really fit tubes in tubeless tyres for that very reason stated - & I think it breaks various vehicle regulations too.....I know we've probably all done it in the past, but if it was found to be the cause of an accident, then you could end up in trouble! Proper 'tube' tyres are completely smooth with an additional layer of rubber on the inside.

The second point is that the different models of the same car have different width tyres depending on their weight & engine size. So if your BMW is a six pot 3 litre & is intended to run on 205 tyres, then it would probably be against the law to substitute a thinner one - then again, you could say, well who's gonna notice? (so long as you're not in an accident & the plod take the car in for an inspection)

So you may as well fix the wheels you have - & I've done no-end & it costs virtually nowt

First, run some water round both sides of the rim to see exactly where the air is bubbling from. Remember to do the same round the valve insert outer, as these are a common cause of leaks on alloys.

The cause of the leakage is generally not from a bad joint between the bead & the rim, but is due to the lacquer starting to lift due to being damaged by years of rough old tyre fitters scatching through it when taking tyres on & off, followed by salt water getting in & corroding the alloy. What I've found happening is that microscopic airways form under the surface of the lacquer that lead right past the bead seal & into the inner part of the rim inside the tyre. This causes an 'air bypass effect' to the outside edge of the bead, so taking them to a tyre fitting place to get them re-seated is often a complete waste of time & money!

You need to break the bead/s - I've got an air compressor & an old bead breaker at home, so this job is easy for me, but you can do it yourself in a very large woodworkers vice with wooden blocks or by lowering the weight of your car onto it with the appropriate shaped block of wood. Or if you really can't do it, then take it to a tyre fitters & get them to break the bead (or beads) for you - but this may cost! Don't remove the tyre from the rim - there's no need......Remember to remove the valve & let the air out first, though

Once the bead is broken, push the tyre back (you can use small blocks of wood to keep the gap open if it keeps trying to close up) & scrape ALL the flaking lacquer from round the inner edge of the rim....scrape it, sand it, whatever, but try not to let muck get inside the tyre - use a vacuum cleaner to suck/blow the sandings/scrapings out of the bead area.

If the valve insert is leaking where it meets the alloy, you can 'sometimes' push/tap them through a bit & use a little cycle tube repair solution round the inside lip & then pull it back through. Often though, they won't push through, or you end up damaging the thread part, so the best bet is to cut off the inside bit with a sharp knife - mind it doesn't drop inside the tyre - & pull the stem out & fit a new one pushed through from the inside.

Once you've cleaned all the lacquer off to an area just beyond where the bead seals, you will now (with a bit of luck) have broken the little air bypass tracks that used to flow beneath the surface of the lacquer.

You now need to use some harmless 'gunge' to seal the porous surface of the alloy & to help re-seat the tyre bead back onto the rim edge. I've used all sorts with success - Duck oil is good & harmless to rubber, plus it helps stop further corrosion creaping into the bead area. I've used Waxoyl, also harmless to rubber.....or you could take an old jam jar to your local tyre place & ask them for a hand full of their propper tyre fitters goo. I've used all of these with no problems, but DON'T use washing up liquid or any kind of soap as it's full of salt & is caustic & will cause you no end of problems on alloy!!

You may find that when you break the bead that the lacquer is in good & undamaged condition & all that's required is a quick clean up & a re-seat with some 'gunge'.

So having cleaned up the rim & applied the 'gunge', you need to re-seat & inflate the tyre - easy for me with the compressor. You could use a foot pump if you can get an air seal started - I've done it & used a rope round the tyre with a bar through it as a tourniquet, but you will have to be fit as you'll be doing a LOT of pumping!! Best bet is to take the wheel to a petrol filling station & inflate it with their air line.....word of warning! - when the bead seats it will go with a loud POP - make sure you don't have your fingers in the way!!! DON'T get your head too close when the bead seats, as some of the 'gunge' may spit out of the joint & go in your eyes - & it will sting!!

So that's it....job done

Just a final thing - if your wheels are 7J x 15 then they will take either 195/65/15 or 205/65/15 without any problem.

[peppiB]

Thank you for all the info - that tyre site is a great place.

HMK - sadly I am currently in not so good health and unable to do a lot of the jobs I used to be able to - highlighted this week when I dropped a 3 ton trolley jack on my fingers badly crushing them, hence my desire just to replace the wheels rather than work on them. My friendly local tyre fitter has ascertained that the leak is on the inside of the rim, covering a distance of 6" or so. If I were more able bodied i would be doing exactly as you describe.

[HMK]

Hi peppiB,

Sorry to hear of your health issues & quite understand your situation

Hope you manage to get everything sorted - perhaps others with leaking alloys will find the above info of use.

I have to admit that alloys are a real pain when they get old & although they look pretty, I would rather have steel wheels....they're a lot less trouble

I've just been editing my previous post correcting all the typos & spelling mistakes (that I could spot) - I really should 'proof-read' before posting