Does Tire Repair Require Alignment?
 

I just had a puncture patched in the front tire of my 987. The car has only 3500 miles but since the tire was removed for the repair, do i need to have an alignment done?

I remember reading in another post about alignment for our cars being complex and requiring special laser equipment. I'm sure like everything else its an expensive procedure.

Thanks in advance for advice.

Not unless your suspension was severely jostled when you got the hole. You may have to balance the wheel, but alignment only adjusts your suspension.

Dealer cost should be around $150.00 for alignment.


However, There shouldnt be a need to have an alignment done just because you "fixed a flat". I have had many flats fixed and never found a need for alignment. Just make sure they properly balance your tire.

great information. Thanks for the replies!

I know this is a controversial topic, but most of what I have read on the subject, patching speed rated tires is not recommended. Others on this Forum disagree.

Patching a speed rated tire is not a great idea. You can do it and get away with it, but your asking for trouble.

If your doing 150mph and it lets go because the tires do get hot then what? You're dead. If it's in the deep part of the tread then usually ok, if its in the shallow part near the wear bars your askin for it but can get away with it. If you on the outside near the sidewall your just retarded for fixing that.

I know tires are expensive but so if your car and life is pricess so don't chance it.

Regarding the algnment, if you hit a curb and poped it then yeah you'll need an alignment. If you just picked up debris off the road, I wouldn't worry so much about it.

HI,

I've been around Racing enough that I've seen many Tires Blowout at high speed. The results often aren't pretty.

I'm not a Fan of repairing a Performance Tire, because the Tire is compromised for further High Speed use. But, there is a repair method which will allow a Tire to perform on the Street (albeit usually for a shortened lifespan). This is the Plug & Patch method.

This requires unmounting the Tire, pushing in a Plug and adding a Patch over the Plug where it protrudes on the inside of the Tire. Then the Tire must be remounted and balanced for a proper repair.

Unfortunately, most Shops do not perform this repair unless specifically directed to do so, and most Drivers are either averse to the added cost - $50+, or oblivious to the procedure altogether and don't insist on it.

As mentioned, you, your passenger and your Car are worth biting the bullet and getting the Tire replaced, and so are the other folks on the road, like me. I don't relish the thought that drivers I'm sharing the Road with are all on compromised Tires. Let your conscience, not your wallet, be your guide...

Happy Motoring!... Jim'99

Hey Jim, what is it exactly that causes a really good plug and patch job to come loose at speed, causing a blowout?

Randall,

The issue is Heat. You increase the Mass (and consequently the Heat storing capacity) in the area surrounding the Puncture allowing Heat to Build-up - you create a Hot Spot.

The main difference between a High Performance Tire and a regular one lies in it's ability to shed this Heat, not in Grip, Water Channeling, or Agressive Tread Patterns. Tires under the stresses of Performance Driving can reach temperatures exceeding 300°F for short intervals. These Temps can soften and reduce the adhesion abilities of the Glue used to secure the Plug and Patch, and they may just come loose.

With this newly created Hot Spot, you compromise the Tire's ability to work as it should and a Heat induced Blowout (at high speed) is more probable.

Not only this, but the Puncture may have also severed some of the Belt Cords, these run diagonally from sidewall-to-sidewall and work in unison. If these cords are severed, they cannot do this and so the strength of the Tire, along a diagonal axis in the affected area, is lessened as well. Hope this helps...

Happy Motoring!... Jim'99

HOLY CRAP! Heat. Never thought of it before. I was always thinking it was a structural integrity issue.

That settles it. No more high speed driving until I can replace all the rubber on my car. I think I've had at least two of my tires repaired.

Actually, I can turn my frown upside down... I really needed an excuse to get new rubber, and the 18 inch rims to go inside that new rubber. This makes me feel a lot better about the upgrade. I'll tell the wife it's a matter of personal safety!

She always lets me play the safety card. After all, she's been training me in husbandry for nearly 20 years now and has a lot of time, energy and emotion wrapped up in the investment.

Small correction to Jim's description of tire construction.
The carcass plies run side-to-side from bead to bead, the belts are under the tread area only.

Thanks for the lively discussion. I have never patched a tire before, for the reasons you mention. However this time there were a few mitigating circumstances:
1. the tire has only 3500 miles on it, it was a simple puncture from debris.
2. the dealers were no help--they said they don't sell tires and refered me to a high performance tire shop.
3. The shop told me the tires were a new model and would take a while to find and get (i guess porsche modified the standard Continental tires for the 987 and they are not widely available).
4. My driving is city driving, with very rare instances of reaching 75 on the congested LA freeways.

That being said, perhaps i should have the shop find the tire and replace it. Another question:
given the low mileage, can i get away with replacing only the one, or do i need to replace the other front tire as well.
What procedure needs to be performed once the new tires are on?

Thanks

TVC What dealer in the LA area did you go to? Also what shop did they send you to?

You should be OK with just replacing the one tire. This is a good question, because you don't want to set-up an unnecessary stagger. New tires are about 10/32. You can measure to make sure you are not setting up a stagger. I doubt it with only 3,500 on the fronts.

You still may want to save the old tire, have it patched, and use as a spare for emergencies- just a thought. You'll need to store it at home.

Hi,

Yep, agreed. I should have better clarified. Thanks for the correction... :cheers:

Happy Motoring!... Jim'99

TVC15:

I haven't had a tire "incident" yet, but being concerned about it is obviously one of the joys of 987 ownership, due to the lack of spare.

Did you even attempt to repair it using the materials (filler and pump (?), I believe) on-hand, if so, how did they work as a stop-gap? or did you get on the horn to a flat-bed straight-off?

Were you in the middle of nowhere, cursing Porsche's decision to drop the spare in favor of more trunk-space?

I called Downtown LA Porsche and Beverly Hills Porsche. Downtown referred me to Globe Tire on La Cienega at Venice Blvd. They were very professional and said that they do a lot of Boxs.

I heard the hissing when i got home on a Friday night. I decided to wait until Sunday morning to deal with it. By morning it was flat.

I called the 2 dealers, was told they don't do tires, and one suggested i call Porsche roadside assistance. Got a nice guy in Florida who offered to flat bed it, made all the arrangements then inofmred me that they would only take it to the dealer.

I explained the dealer didn't do tires. He said that they would tow it to the tire store but only ** it was taken to the dealer and the dealer would have to issue the instruction to tow it to the tire store (!) Competely idiotic since the tire store is a half mile from my home and the dealer is 10 miles in the opposite direction. Said thanks, but no thanks to Porsche roadside.

Talked to the tire shop, they warned about using the gel; every trace of the gel must be removed (very difficult and no guarantee) or the tire can't be patched.

Called the auto club, and was told that no flatbeds were available until Monday (2 days). they sent a truck out with air, inflated the tire and i drove to the tire store.

All of this an I live the the middle of LA--can't imagine what would have happened if i had been in the middle of nowhere.

Sorry about the length probably much more than you wanted to know . . .

Hey your right in my area....best place that i would say to go is Wheel Enhancements in Culver City....They ONLY do Porsche Wheels and Tires nothing else. I would listen to them, they are the only ones i trust replacing my tires...

Let me know if i could be of any help to ya...

"Sorry about the length probably much more than you wanted to know . . ."

Not at all, I always appreciate it when someone takes the time to provide detailed responses.

"Another question:
given the low mileage, can i get away with replacing only the one, or do i need to replace the other front tire as well."

The owner's manual states that up to 30% difference in treadwear is permissible on the same axle.

------

So reading your post prompted me to do something that I've been meaning to, and that is check out the emergency tire-inflation equipment that comes with the car.

For what it is, I'm mildly impressed. The air compressor looks to be of high-quality (plugs into the cigarette lighter). I guess the upside to this is that if I need to put air in my tires I no longer need to go to a gas station, which is pretty cool.

The sealant goodies stocking stuffer looks more robust than the can of "fix-a-flat" available at Los Tres Amigos, but obviously is limited in the situations it can be applied.

The stuff is accessible by unlatching the compartment at the bottom of the front trunk. I also found the little tool kit, I've read about.

All told, I feel a little better, but suspect that one day we'll read about some poor 987 owner whose bones were left to be picked over by prairie dogs when he caught a flat in the Mojave.