Tyre Seals and Knocking Noises - Hawesy1982
Hi all, bit of a dual niggle to plead for help with today,

firstly there's been a lot of knocking noises coming from my 306 recently, due to uneven roadsurfaces. It's not affected by engine or road speed, just the road surface quality. From my Haynes manual i think it is probably worn anti-roll bar drop links, but anyone who can confirm this/offer other ideas would help me commit to replacement ones.

secondly, my front left tyre has been dropping to around 20psi for quite a while now. I reinflate to the recommended 33psi every week, but after a few days (at 50miles/day) it's back to 20psi, yet doesn't drop any further. I can only assume that the beading or value is leaking, but don't know a way of telling which. I was informed by a friend of mine that one manufacturer (maybe Honda or Toyota?) is now selling new cars without spare wheels, and instead treating the wheels with tyre sealant. Is this true? And if so what do they treat them with, and can i use it to help my wheel hold pressure?

Thanks in advance for your ideas
Tyre Seals and Knocking Noises - Armitage Shanks{P}
If you have alloy wheels your problem might be a porous casting. I had a Golf, with 5 alloys, years ago and had 2 wheels exchanged under warranty, one tyre went completely flat and the other went to about 20psi and then held it. I located the leak by taking the wheel off and totally immersing it in a very large sink - the air could be seen bubbling out of the metal of the wheel, not a valve or rim. If you don't have alloys then I still suggest the total immersion test.
Tyre Seals and Knocking Noises - Hawesy1982
I do have alloys, so that could well be the case, thanks for the tip.

In which case if it is, what's the fix? Some kind of sealant on the alloy itself?
Tyre Seals and Knocking Noises - Phil I
In days of yore we used to just bung an inner tube in and away you go, but this is very much a nono now. You could try a can of Holts Tyre Weld but this is not recommended.
Tyre Seals and Knocking Noises - Dynamic Dave
I do have alloys, so that could well be the case,
thanks for the tip.
In which case if it is, what's the fix? Some kind
of sealant on the alloy itself?


Only sure way is to get the tyre off the rim, clean up the mating surface and remove all the loose flaking paint ,and then repaint. I found Finaghans Smoothrite in aerosol format very good for this. The silver is even a good colour match.

You will not get a perfect seal if you use sealant alone. The loose flaking paint will just cause the seal to leak again.
Tyre Seals and Knocking Noises - Mondaywoe
My Mum has an L Reg Clio. She only uses it once a week. Because it loses about 5 psi on each wheel over a week it has to be pumped up every time she uses it and as she's 77 that's not much fun! It's been to the tyre centre, had all the rims buffed smooth and tyres re-fitted - waste of time!

This week, I decided to phone around scrappies to try and get 4 decent replacements. They all told me I'd be wasting my time - Clios are notorious for leaking at the rims.

To cut a long story short, I ordered 4 new wheels (steel)from the Renault dealer. Surprisingly, they were only £26 each - not a fortune really. Problem now solved.

Graeme
Tyre Seals and Knocking Noises - sean
Hello Hawesy,

This is simple to find and the comments here will help you to fix it.

I'm referring to your leaky tyre.

Nip up and run yourself a bath of cold water. Get it about a foot deep.

Whip off yon leaky wheel and immerse it in the bath.

Leave for 10 seconds or so, till calm tranquility returns to the water.

Now look. HARD. What you will see are bubbles, small but lots of them.

If they're coming from underneath, whip the wheel out of the bath, turn it over and do it again.

You will then know whether leak is from wheel, tyre or valve.
Tyre Seals and Knocking Noises - M.M
>>Nip up and run yourself a bath of cold water. Get it about a foot deep.

Whip off yon leaky wheel and immerse it in the bath.


Sean either you're not married, you have five bathrooms and two maids...or you're German.

Not sure which.

M.M
Tyre Seals and Knocking Noises - sean
Gott in Himmel,

Fantastiche.
Tyre Seals and Knocking Noises - pastyman
to ,Hawesy 1982

Try taking off the affected wheel, you\'ve then got 2 choices, rotate the said wheel in a bath of water to detect any leak, or, make up a very bubbly mix of washing up liquid in a mug, then using a old brush, brush onto all the possibly affected areas, i.e. both beads and the valve mounting. Also dont forget the welds in the rim itself, its not unknown for these to crack and leak.
pastyman
Tyre Seals and Knocking Noises - Greg Parker
Related to the topic of tyre sealants. I would be tempted to take out the spare wheel for better fuel economy and less weight for shorter journeys and have some tyre sealant ready in the event of a puncture.

I used ultraseal which sits in the tyre and instantly seals any puncture on my motorbike. It also said it reduces tyre wear by reducing heat. They are cheap and range from £5-20 to cover four tyres. The ultraseal paid for itself as I had about three punctures over the course of 10,000 miles which self repaired. Note that to fix a puncture costs about £10.

However, the problem is if the puncture comes from the sidewall in which case a whole new tyre is required.
Tyre Seals and Knocking Noises - Hawesy1982
Thanks for all your comments thus far, i will see if the wheel will fit in the bath this weekend, as my parents are away on holiday til Wednesday and so cannot shout at me to 'get that dirty thing out of the bathroom!'
Tyre Seals and Knocking Noises - IanT
Since everyone else has ignored your knocking noises problem ...

If the problem is the antiroll bar drop links, I think you will find you get knocking noises on uneven surfaces (front wheels moving independantly) but not when going over speed bumps (front wheels moving in same direction at same time).

Check the drop links by testing for play in the ball joints - particularly any movement when trying to pull the link away from the ball joint. If you're a good wriggler, you don't even have to jack the car up to do this.

Drop links are (relatively) cheap and easy to replace. There are two types - plastic and something else, so make sure you know what's on your car before buying the new ones.

Ian
Tyre Seals and Knocking Noises - Hawesy1982
Thanks Ian, thats precisely whats happening wrt speed bumps and uneven roads, just glad its only a £32 do-it-yourself fix this time as everything seems to be falling apart in the last few weeks!
Tyre Seals and Knocking Noises - c-lant

If you probably find it is leaking around the bead / rim. If you have alloy wheels this is a common fault. A way of testing is washing up liguid and water put around the rim edge and obviously inflate tyres first to recommended pressure. There is a product which is used in the trade, they break the tyre bead down and squirt between tyre and rim brush around and inflate. This product works well.

 

Value my car