Plugging a flat - lessons learned

[bwilson4web]

After visiting a hardware store, a flat:

The offender is in the upper left corner.

Some sort of sheet metal screw based upon the head:

Using a flat, get it high enough to grasp the head:

Needle nose, vice grips make it easy to unscrew:

More easily than trying to remove with the flat screw driver:

Here is the little bugger. The flat head allows it to rest in the parking lot, pointy end up:

Unfortunately, no space to work on the repair. So a handy biological (pine needle) went in the tire so the car could back up enough to work on it. I probably should have just backed up with the original object to make it easier to take out:

So here is the plug in the 'needle' tool to insert. The infernal needle tool:

Covered in adhesive, it made an impressive wad and would not go in the tire. I briefly thought of backing up over the tool to force it in ... but came up with another approach.

I had 'rasped' the hole larger but decided to try a flat screw driver:

It appears to have worked. The wide-side of the flat screw driver avoids clumping up the plug at the entrance of the hole. I am thinking about getting a similar flat and grinding it in about 1-2 mm with very narrow shoulders. The wider surface area will avoid the clumping.

So I put a plastic bag over the external, patch wadding, and backed over it:

Now to go test it.

Bob Wilson

 

[alohart]

By the looks of the tread, I'd say that this tire isn't worth spending too much time trying to save. However, it is good for learning how to plug a tire worth saving in the future.

 

[rtanov]

Thanks for the tutorial. My wife got the exact same screw last week, was close enough to home to bring the car in. Took the wheel to Costco to use their hazard warranty, they fixed it within 1/2 hour, free of charge.
I also have the same plug kit in both out cars but have not had a chance to use yet. Hope it stays that way

 

[i3Houston]

Ditto last week. Luckily I had inflator so I made it back home after making several stops to inflate.

Nail was on the rear passenger inside wall, that area is extremely hard to reach, plugging it seems impossible!

Costco replaced it but the tire guy was claiming that i3 doesn't qualify for mileage warranty because tires are staggered.

 

[jadnashuanh]

Tire industry does not recommend any hole outside of the tread area to be patched...it must be replaced.

 

[bwilson4web]

PART 2

Weeks later, the repaired tire pressure was down to ~30 psi but I had an appointment. A slow leak, I inflated the tire and made my appointment. It was down ~5 psi after the appointment so I fetched some groceries and went home where the pressure was down ~14 psi (1 bar.) Breakfast and a nap waiting for the afternoon warm up and back to finding what went wrong.

FINDING AND FIXING

I could not get the jack under the car:

So I removed the front wheels:

I still had a problem as there was no room for the lift plug:

So I repositioned the car to let the passenger side front tire lower which provided enough lift for the driver side rear:

I was just able to get the jack under the lift plug:

More about this later.

So where did this bad boy come from:

A pointy stone, I got out:

The soapy water test confirmed the original plug was working fine. The new stone puncture was the problem:

Wearing disposable, rubber gloves, this time I trimmed the string and left it as shown:

It almost worked! BTW, notice the wear bar still has some space relative to the tread. The tire is in the replacement range but I've twice (soon three times) plugged this worn out tire ... practice!

So I packed everything in the trunk except the break-over with the 17 mm socket and extension.

Opps! Spoke too soon

The next morning, it was flat again. The soap test confirmed a slow leak in the 'stone' patch:

• scraped to find the patch plug
• rasped out the plug - found a rubber tab not seen before so I used a knife to take it out
• sun warmed the plug kit and tire hole
• while slightly depressing the tire, put a slug of sealant on the hole then let up to draw it into the tire thus coating the sides
• trimmed another plug and throughly coated with sealant
• used flat screw driver to drive it into the hole with a twist
• did not trim the string, this time
• put disposable rubber glove over plug and mounted tire so the plug was on the bottom
• inflated tire and let tire and glove on full pressure and car weight

Things to do:

• car jack: replace front axle with bolt, washers and nuts to hold the sides fixed; remove rear wheels to minimize height, and; trim or remove the inner cup to reduce hight (favoring removal.)
• car jack handle - get a socket rachet wrench with a 17 mm deep socket to be the new lug wrench

Bob Wilson

 

[jadnashuanh]

Plugging a tire from the outside should never be considered a permanent fix. The only approved method is a plug patch applied from the inside.

 

[alohart]

car jack: replace front axle with bolt, washers and nuts to hold the sides fixed; remove rear wheels to minimize height, and; trim or remove the inner cup to reduce hight (favoring removal.)

It would certainly be easier to buy a jack that will fit under an i3's jack points and has a flat lifting pad large enough on which to safely place a jack point adapter. I've used such a jack to lift our i3 onto and off of jack stands on 3 occasions.

 

[bwilson4web]

Plugging a tire from the outside should never be considered a permanent fix. The only approved method is a plug patch applied from the inside.

Actually I have new replacement, rear tires, just waiting for nice weather. This is the most worn tire and perfect for learning how to do a field plug.

As for my jack, it was on sale one day and I got it as a general purpose solution ... we have more than one car. I was surprised by the height problem and considered other options like a cheap scissors jack, a 2-3" high wedge, and an alternate jack point on the wheel linkage. But I think reworking this jack will work:

The jack handle now has a 3/8", flexible racket head and a 17 mm, deep socket.

The front axel should be fairly easy. Cut the middle with a metal blade and replace with a long bolt, four washers, and three bolts with loctite. The rear wheels just unbolt. I'll replace with stubby bolts to preserve the wide stance for stability.

The lift cup spreads the load so it won't punch through is a challenge. If I grind or cut off the 'teeth', we'll save about 1/4". The other option is to look for or fabricate a replacement. I'll make the other mods first and remeasure.

Bob Wilson

 

[bwilson4web]

Third time's the charm. No loss of pressure.

Bob Wilson

 

[bwilson4web]

Here is my first, successful plug from the inside:

I had to do the second one twice. The key was letting the sealant fill the reamed hole. The first plug failed with a slow air leak. Internally, there were two plugs:

Since I replaced the Prius Prime with a Tesla Model 3, the BMW i3-REx is now the backup. So instead of further experiments, I had the local tire store mount the tires. But the jack worked great:

Bob Wilson

 

[jadnashuanh]

Since you had the tire dismounted, why didn't you put in an industry standard plug patch? Do that once, and it doesn't leak, won't let moisture into the carcass, or degrade the tire further.

 

[bwilson4web]

Since you had the tire dismounted, why didn't you put in an industry standard plug patch? Do that once, and it doesn't leak, won't let moisture into the carcass, or degrade the tire further.

The driver side tire after ~36k miles was worn out:

• inner, shallow groove had disappeared
• middle groove was just about at the wear bars
• outer groove was shallow

I was planning to replace both rear tires and had the news ones already from Tire Rack. I was waiting for good weather.

The passenger side tire was less worn, ~25k miles. The original hit some road debris that sliced the sidewall. I prefer tires matched for tread depth and wear.

This also gave me a chance to test the jack and tire changing procedure. I found the 3/8" ratchet wrench failed to take off the lug bolts by 'clicking under load.' So I went with a break-over which worked perfectly. I will include a socket sized to replace the pump receiver and throw out the original, jack handle.

Bob Wilson