Tyre puncture

[Jamesc]

On 2/24/2024 at 2:57 PM, kykh said:

 

I discovered a screw that had punctured into my relatively new tyre when I parked my car with its front wheels turned to one side incidentally. I'm not sure how long the screw had been lodged there, but nothing was amiss when I was inflating the tyre recently and it did not appear to have been deflated. Nevertheless, I drove to my usual tyre shop and the mechanic, upon extracting the screw, performed a simple leak test by spraying soapy water at the punctured spot, and it showed no sign of air leak. He explained that the puncture might be shallow with the short screw, while I also suspected it might have helped that the penetration occurred at an angle and near the groove, so that the affected spot did not leak and no repair was necessary according to him. I believe that he might have to deliberately create a larger hole in order to plug it with a patch strip and the larger hole would make it worse. Nevertheless, should I be concerned that the affected spot might be weakened and susceptible to rupture while I drive? Thanks!

If you don't deep penetration you don't want a bigger hole.

[Columbian78]

Sharing my new case of tire kenna screw again.

See my posts back in 17 May 2023 in this thread, that time the screw caused air to leak and I changed tyres. All sets are run flat.

This time does not seem to be leaking, yet, after 2 days. I have TPMS and the numbers have not dropped.

So I am thinking to continue driving as normal if it is not going to leak. I have run flats anyway and I can monitor fr TPMS.

The screw is at the edge so it might not be peirced through.

We can hear some abnormal road noise since yesterday so I guess thats when it started. But the noise is very slight only me and son can hear. Wife don't know.

If it starts leaking then it means there is hole thru, then I do the worm repair myself.

 

 

Edited June 30, 2024 by Columbian78
inc photos

[Columbian78]

Update and sharing:

A few days later I could not find the screw head on the tyre and I could no longer hear that weird road noise. It seems the screw had dropped but I am not sure if the stem is still lodged in the rubber as I can not find any signs of it. There had been no loss of pressure from monitoring the tpms so far.

Lesson learnt this round. First is never quickly pull out the foreign object. In last year's case, it quickened the air leakage rate. In this years case, the screw was at the edge and maybe it was not deep or cause leakage. So observe first.

[Beregond]

On 7/8/2024 at 9:31 AM, Columbian78 said:

Update and sharing:

A few days later I could not find the screw head on the tyre and I could no longer hear that weird road noise. It seems the screw had dropped but I am not sure if the stem is still lodged in the rubber as I can not find any signs of it. There had been no loss of pressure from monitoring the tpms so far.

Lesson learnt this round. First is never quickly pull out the foreign object. In last year's case, it quickened the air leakage rate. In this years case, the screw was at the edge and maybe it was not deep or cause leakage. So observe first.

Dun worry. For this type of scew its very very very unlike it will break and leave the tip inside the tyres.

If u want to pull out any nails. Or object. Just put some soap water over it. And slowly pull out a bit. See if any bubble. 

No bubbles then it quite safe.

[Gnahp]

right rear tyre pressure a bit low just now

 

sian, want to rest for a week not working on cars also cannot....

 

[Kklee]

On 7/9/2024 at 8:34 PM, Gnahp said:

right rear tyre pressure a bit low just now

sian, want to rest for a week not working on cars also cannot....

 

IMHO.
Want to rest is can - exchange labour with $. 

[Gnahp]

On 7/10/2024 at 8:02 AM, Kklee said:

IMHO.
Want to rest is can - exchange labour with $. 

I inflated the panjit tayar at 6am this morning

it didn't shows any drop in pressure after 15 hours

I think it is a very slooooow leak

I may not do anything to it as the rear tayar are due for replacement in a month or two

 

[Kklee]

On 7/10/2024 at 9:14 PM, Gnahp said:

I inflated the panjit tayar at 6am this morning

it didn't shows any drop in pressure after 15 hours

I think it is a very slooooow leak

I may not do anything to it as the rear tayar are due for replacement in a month or two

 

IMHO
Got any movement of the vehicle?  IIRC, no movement, the pressure will be quite ok. 

[Gnahp]

On 7/10/2024 at 9:19 PM, Kklee said:

IMHO
Got any movement of the vehicle?  IIRC, no movement, the pressure will be quite ok. 

drove about 100km today

[Gnahp]

those are warm pressures

cold pressure is 260kpa for all four

[Kklee]

On 7/10/2024 at 9:29 PM, Gnahp said:

those are warm pressures

cold pressure is 260kpa for all four

IMHO.
By any chance it is an ICE and the exhaust is on the left ?

[Gnahp]

On 7/10/2024 at 10:06 PM, Kklee said:

IMHO.
By any chance it is an ICE and the exhaust is on the left ?

it is an ICE car

longitudinal front engine, exhaust down pipe at the driver side, exhaust pipe stay centre in the middle and split to a Y around the rear diff to two left and right muffler

driver side muffler blow exhaust all the time

passenger side muffler controlled by a butterfly valve, will only open and blow exhaust in Sport mode and above

[Kklee]

On 7/10/2024 at 10:27 PM, Gnahp said:

it is an ICE car

longitudinal front engine, exhaust down pipe at the driver side, exhaust pipe stay centre in the middle and split to a Y around the rear diff to two left and right muffler

driver side muffler blow exhaust all the time

passenger side muffler controlled by a butterfly valve, will only open and blow exhaust in Sport mode and above

IMHO.
My take is that the side the exhaust is on,  there usually be elevated temperature by 1-2°C.
Depends on the engine ( capacity, turbo, etc ),  the elevated temperature can be more.
In you case where the exhaust is mostly rear right (driver) ,  it is possible that you are having a leak just
it could be masked by the increase in pressure cause by the elevated temperature.  

My take on the rule of thumb that every 1°C increase will cause pressure to increase by about 1.25 kPa.
If the rise is 2°C, the pressure will increase by 2.5 kPa and if 4°C will be by at least  5kPa.
It is difficult to ascertain because of the tolerance of the sensors.  

At first I thought that you vehicle was an EV - seldom possible to have front / rear to have consistent temperature at both side i.e FR=FL and RR=RL. 
Probably good to check the pressure after 6-8 hours after the wheels temp are normalized to ambient. 
 

P.S.  IIRC,  i had something similar to that object.  Went to the tyre shop,  they pull it out,  no puncture, just embedded.🤣

Edited July 10, 2024 by Kklee

[Gnahp]

On 7/10/2024 at 10:52 PM, Kklee said:

IMHO.
My take is that the side the exhaust is on,  there usually be elevated temperature by 1-2°C.
Depends on the engine ( capacity, turbo, etc ),  the elevated temperature can be more.
In you case where the exhaust is mostly rear right (driver) ,  it is possible that you are having a leak just
it could be masked by the increase in pressure cause by the elevated temperature.  

My take on the rule of thumb that every 1°C increase will cause pressure to increase by about 1.25 kPa.
If the rise is 2°C, the pressure will increase by 2.5 kPa and if 4°C will be by at least  5kPa.
It is difficult to ascertain because of the tolerance of the sensors.  

At first I thought that you vehicle was an EV - seldom possible to have front / rear to have consistent temperature at both side i.e FR=FL and RR=RL. 
Probably good to check the pressure after 6-8 hours after the wheels temp are normalized to ambient. 
 

P.S.  IIRC,  i had something similar to that object.  Went to the tyre shop,  they pull it out,  no puncture, just embedded.🤣

i agree with everything you said 👍

unfortunately (fortunately actually 😁), that car only gives pressure reading in the increment of 5kpa, and it only updates every 2 minutes, can't make any useful analysis from that

also, it won't show the pressure immediately after starting the engine, it will only show the numbers after about 500m drive

this is the pressure after 500m when leaving office just now

even though all 265, it could be anything between 263 to 266

[Kklee]

On 7/10/2024 at 11:28 PM, Gnahp said:

i agree with everything you said 👍

unfortunately (fortunately actually 😁), that car only gives pressure reading in the increment of 5kpa, and it only updates every 2 minutes, can't make any useful analysis from that

also, it won't show the pressure immediately after starting the engine, it will only show the numbers after about 500m drive

this is the pressure after 500m when leaving office just now

even though all 265, it could be anything between 263 to 266

IMHO.
That's why need the manual digital gauge and IR temp gun. 
Your 5 kPA cannot compare with my 10 kPA.  🤣
So far did not look at how long it takes to update. 
The issue with mine is that every time I start the car,  I have to manual set the dash to display the pressure panel.  According to BM (Toyota), it is like that ? 🤣
Because the built-in TPMS does not have temperature, I install an external TPMS.
It is a very-low-cost model such that the update takes a long time to refresh, one of the sensor is off by 1°C and maybe a few kPA.🤣

Anyway since u r changing soon,  it is a good way to check if the TPMS is working. 

 

[Kklee]

IMHO.
I tested my car TPMS - about 1 minute and 120m. 

[Gnahp]

don't DIY, pay $10 let people do it

it's not worth the effort 😅

[Kklee]

On 7/14/2024 at 5:54 PM, Gnahp said:

don't DIY, pay $10 let people do it

it's not worth the effort 😅

IMHO.
Er.... DIY still leaking ???

P.S.  I bz looking at the Knipex. 🤣