Bruce In Philly

2009 C2S 126K miles

Another flat.... this time a screw in the left rear. Nothing worse that getting screwed in the rear.

So I DIY's with a Smittybilt plug kit. Warning! You must replace the rubber cement tube after one use... mine was dried solid.

Pulled into the train station and pop! The warning light came on, "Flat Tyre" (very British). That evening, I pulled out the Porsche pump, tire back up to pressure fast. What a great pump. No need to buy a "real" pump. The darn thing works fabulously.

Made it home fine.... pulled the tire, and shure enough, I was screwed. The Smittybilt kit worked wonders..... but.... things did not go the same as when I plugged a tire with in on I80 before. Lessons learned..

Read about my I80 plug story here: https://rennlist.com/forums/997-foru...p-goo-bad.html

1. The rubber cement tube was dry from opening it once before. So, I went ahead and plugged it without the cement. I had already pulled the screw so no driving on it.
2. I had a heck of a time pushing in the new plug.

I used soapy water to truly see where the leak was, and after the plug to see if it held. (Soapy water will bubble over a leak.). BTW, that was the second of two screws I found in the tire... the first didn't penetrate the belts and the soapy water proved it was not a problem.

Regarding the hard time pushing into the screw hole..... you need the lubricant of the cement, and you need to use the reamer way more than you think you do. The first time I plugged a tire on I80, the puncture was bigger. The whatever was thrown out of the tire but left a big hole. This and the new tube of rubber cement made pushing in the plug really easy... I did it laying on my side reaching under the car so I really didn't have much leverage to push.... was easy. This time... I had no cement and the screw hole was much smaller. Full disclosure: I had to plug it twice. The first time, I was lite on the reamer, then I think I pushed the plug in at the wrong angle and hit a belt. I could not get that rat in there, so I pulled it out, cut the plug, and reinserted the reamer again and pushed through whatever plug was in there. Gave it a good ream... then still had trouble pushing that darn plug in there. It was tough and I had to put my weight on it. Again, I didn't have any rubber cement as lubricant, so I don't know what the difference would have been, but it sure should have helped.

The Smittybilt is a good kit, but it has way too much stuff in there. I like it because the tools are metal (I had to really put weight on it), they give you a pair of needle-nose pliers to pull out the screw, a razor to cut the plug, and way more plugs than I think I will ever need. Other than that, the rubber cement went dry after one opening. (I used my own pliers, razor, and pressure gauge simply because I had them out and ready.) You really don;t need the pressure gauge as the Porshe pump has one with a red-line to denote proper pressure and the razor really isn't necessary, just drive on the tire and the rubber plug will wear away.

Anywho..... DIY like a man.

Peace
Bruce in Philly

BIG smoke

Good job Real man bruce from Philly.
Lube does help. Other suggestion? wear gloved, to limit the "what ifs".

No soapy water? spit works great.

ocgarza

Always a good reminder. I guess that kit is just the right protection when you screw

ThomasCarreraGTS

ADias

1 - There are tire plug kits which do not require a separate cement tube. Griot's has a good one, or you can get similar plugs elsewhere.
2 - It appears to me that that puncture is too close to the tire shoulder, thus the tire should be replaced.

Bruce In Philly

Update,

Do you know it is near impossible to find an old fashioned tube of rubber cement? Lowe's didn't have it... although they had some shoe repair stuff which I suspect was rubber cement. Anywho, a really big grocery store had a small bottle of Elmer's Rubber Cement I then purchased and that jams OK into the Smitty kit.

TIre holding air fine.

Regarding being too close to the sidewall.... maybe... I did some research, and there is common "industry" guidelines that say my tire is probably, borderline, not repairable. What I can't find, is why this is so. I suspect if has something to do with the flexing and belts moving causing tread separation. Another issue is water getting in there and corroding the belts.... I am not concerned as these plugs are pretty gooey and our tires just don't last all that long anyway. Also, I have had tires professionally repaired closer to the sidewall than this and never had an issue.... I suspect the first sign of trouble would be balance going out or more air loss.... never had this issue. I only had one tire shop ever deny a repair due to being close to a sidewall, it was a big chain and they had a policy (safety or to sell more tires?). Otherwise, if close, they will repair but not guarantee the repair will hold air... I guess because of the increased flexing at that spot. Most of what I am posting here is my speculation and experiences.... I just can find any real science on this. I posted a vid below produced by some tire association which provide some cool stuff.

So what to do? I am going to go with what I did and not replace the tire (I would do both rears if I did to keep everything equal). I feel (yes not scientific) the hole was not large at all and little if any belt damage (hence the difficulty I had pushing in the plug), the screw was not that close to the sidewall to get the wall flex (this I feel is still a "flat" area of contact), and I will probably replace the tire next summer given the tread wear (I will put on winter snows for the winter). Even at the track with huge lateral force, I never saw evidence of my tires rolling over that far at all as you can see the scuff line on the tread edges which you can vary with tire pressure.

Your opinions? I would like to hear about some real science.

Update: I found this on Discount Tire.... given their guidelines, my tire is repairable.... " 1/2" from tread edge".
https://www.discounttiredirect.com/learn/tire-repair

They also note plugs alone are not acceptable... because they may not hold. I don't care about this... I watch this stuff closely and if it doesn't hold, oh well, I will just buy two new tires.

Peace
Bruce in Philly

AreaOne

Bruce In Philly

Hey that looks great! Something that really worried me..... if I encountered the same struggle inserting the plug out on a highway with the tire on as I did at home with the tire off, I doubt I could have completed the repair. So in the two repairs I did myself, the one on I80 with the tire on the car was easy as the hole was big... this recent one at home was tough as the hole was small. This system appears easier. Stop & Go makes an easier model.... check this one out... and then a guy compares three types and he comes up with an iteresting conclusion.....

I am going to do some research I may just buy the one with the gun. I've had two flats in the past year and about had it..... for me, this crap is real and I need something easy.

Peace
Bruce in Philly

Stop & Go with gun

Camparo......

AreaOne

latonnelier

I'm with Bruce.
I just ordered the Stop & Go. I've had 3 punctures (in addition to 2 road hazard warranty uses, and a manufacture defect) on our 4 cars in the last 2 years. The roads in Tucson are just littered with the "ejecta" of every work vehicle in town. Every time I get screwed it costs me money.

rootwyrm

Science hat on!

It's an issue because of what it does to the overall structural strength of the tire, the location of the belts, the temperatures, and the effects of loading on the tire. Basically, even with rubber bands, you've got a LOT more flex closer to the sidewall when cornering. Even at low speeds. Even for non-steering wheels. This is just how the physics are. So you have dramatically higher chances of catastrophic failure of the tire, including tread separation and sidewall failure. I'm not saying it will happen. I'm saying that it increases the probability. The shorter the sidewalls, the higher the load here, and you're right on the edge of the wear cut. HOWEVER, it's a really small and short puncture on a non-steering tire with plenty of tread. So this is the kind where I might do a glue patch solution instead. (However, doing a glue patch correctly means dismounting the tire. Pretty much same as patching a bicycle tire. But hey, it's good enough for 100 ton dump trucks.)

I hate Discount Tire's guidelines because they're completely arbitrary. 1/2" from tread edge has a totally different impact on a 70 than a 35. It's a reasonable starting point, but I'd rather look at the wear pattern. Sometimes it should be a full inch and a half, sometimes you can get practically to the shoulder and be fine. But these days, everybody slaps the plug disclaimer on there because they want to sell you a tire and avoid liability for shoddy repairs. I've only had plugs fail on holes that were too big or when they were improperly installed or the plug was dried out crap.

Honestly, my only concern with your repair was needing to force the plug through. It's not really that big a deal at all, but it's something I was taught to avoid doing, since it could make the puncture worse. Basically going from unbroken belts to broken belts. It's not going to kill the tire or kill you though. And obviously if it's holding, it's perfectly fine. It's just that there's a chance that when you force it through, you turn a fixable tire into a scrap tire. (And if you told the customer "yep, we can patch it" and then you can't, well, yeah.)

But really the best thing you can do for yourself and your tires is learn how to use plain old awl and punch style plug tools. Using the right tools is important when you can, but if you know how to do it, when you get stranded without the fancy tools you'll still be able to put in a plug with nothing but a pair of pliers and a ball point pen.

vg247

Bruce In Philly

Dude, you da man! Free beer for you.

Tell me about that gun...... was it difficult to push in the plug? Did the gun make it easy? Did you do it with the tire off of the car or were you laying in the dirt with semi-trucks whizzing by (you get extra beer for that one). Where the plugs gooey.... the regular patch plugs are super gooey and one of the reasons I don;t worry that they will allow moisture in or "wear out".

Regarding your question re should you get it professionally repaired.... as you read, some here say "absolutely". I don't share that concern... I would just keep aware if you get air leakage or vibration. Given you only have 200 miles on the tire, maybe I would go ahead anyway and have it repaired.... but that would depend on my mood. BTW, I am just some guy on the internet... what do I know? Full disclosure: Professionally, I am a canine brain surgeon. No really, I am a canine.

Peace
Bruce in Philly

jfort

I, too, had a flat tire recently. I had a plugging kit. The cement was dry. I reamed it good but still had trouble getting the plug in. A little engine oil from my standby quart helped. It held perfectly for the whole weekend, but the next Monday I had it patched from the inside. Later, I found my DynaPlug kit, which I think would have worked better. Also, I have to add, my son was driving the 997 following me in the Cayenne where I have all kinds of tools and emergency stuff. The biggest problem we had was using a scissor jack and that jointed rod that comes with it. Afterwards, I gave it more thought and knew there must be a better way. I found and ordered a 1/2" adaptor for the jack. Now I can operate it with the impact wrench. It would have been a __itch trying to plug the tire on the car.

vg247