TR2/3/3A Tire Inflation Puzzler

[PatGalvin]

Hey Guys

So, I get up early Saturday and sponge bath the TR3A and fill all the tires up to 31 psi. My powdercoated stock steel wheels seem to lose a few pounds of air after a few weeks so I have to top them off before a significant trip. I was heading to Blackhawk (Northern California) and had a 110 mile trip door to show. I hit the road at 6:30 AM and took the freeway and was doing about 75 to 80 mph for the first hour and 15 minutes of driving. Then, I noticed my steering was getting really heavy and uncomfortable so I slowed and pulled off. My front tire was flat. I changed to the spare and dropped the flat off at the tire store for a fix. Then, when I arrived at the show, I noticed my PS rear tire was low - it only had 13 psi. And another wheel was at 23 psi. So, I topped off all the tire inflations and went back after the show and picked up the flat-fix tire. Tire shop said that there was no problem and it held 50 psi all day. As info, I often take drives of up to an hour but not the high speed touring of this trip. I've never had a sudden tire inflation problem like this.

The puzzler? What could cause the tires to deflate at high speed? I have had one rim repaired recently. A wheel shop welded a pinhole shut to repair the rim. But, I can't understand what is occurring at extended duration high speeds that would cause the tires to deflate? The tire shop guys thought maybe the wheel weight clamps might be laying across the tire bead and affecting sealing. But, all my wheels have weights and it's never been a past problem.

Any ideas? I'm thinking of just having tubes installed in all, but would really like to understand what could be happening here.

Pat

 

[PatGalvin]

Just a show photo for your enjoyment.

 

[pa297pass]

Original 4" TR3 wheels have the centers riveted (not welded) to the rims. Could the rivets be leaking? Maybe the higher speed driving flexes the wheel more so they leak more, but it would also explain the slow leak you have even while sitting.

Matt

 

[tinman58]

Hey Pat
According to Rod, the triumph wheels should have tubes. I guess I was lucky with my rims and tires with no tubes. It was a good day at the show.

 

[TR3driver]

The wheels get pretty hot during sustained high speed driving, but heated by the tire rather than by the hub. Might be differential expansion causing the rivets to leak.

Years ago I had a somewhat similar problem with a riveted wheel on my motorhome. A good heavy coat of paint inside the wheel stopped the problem.

 

[Geo Hahn]

This is what I use to seal spoke ends on wire wheels, something similar (or possibly 3M window weld) should seal rivets if mere paint isn't enough.

 

[PatGalvin]

Hey Pat
According to Rod, the triumph wheels should have tubes. I guess I was lucky with my rims and tires with no tubes. It was a good day at the show.

Thanks Dan
I've gotta find someone that will fit tubes to tubeless tires. None of the big tire shops will touch it.

Here's a pic of Dan's TR250 from the Saturday show. Looking pretty fantastic!!

Pat

 

[TR3TR6]

Pat, you might also take a close look at the rims to make sure they are nice and smooth. When I had spokes on my car, I put tubes on them with the tubeless tires; didn't have any leaking problems.

 

[pdplot]

Find some old geezer who's still running a small shop. He'll know how to do the job.

 

[CJD]

+1 with the tubes. If it's a problem, you could likely seal the rivets just like Geo does with the wire wheels, though.

 

[TFB]

+1 with the tubes. If it's a problem, you could likely seal the rivets just like Geo does with the wire wheels, though.

I have no tubes with my steel wheels which I believe was the original setup,no problems.
I seem to recall reading on this forum that tubes in a tubeless tire can be chafed by the inside tire surfaces which may not be as smooth as a tire made for tubes.
Tom

 

[PatGalvin]

Thanks for all the comments and ideas. I am going to take the wheels over to a custom wheel shop that does all the wheel repairs for the Sacramento area. They are magicians when it comes to wheels. They said they would be happy to look it over and try and see if they can figure out how the tire lost all that air so quickly. I'll circle back and let you guys know what I find. I had them weld up one faulty wheel (pinhole at seam where the outer wheel was welded together) but cost out the door was about $170. I don't intend to spend that again! Many folks really like the steel wheels and globe hubcaps, so I'd like to keep them.

pat

 

[SteveBones]

Pat,

I can not offer any additional suggestions or ideas. I like the idea of using some silicon or other sealer to use around the rivets. I bit of a pain because you would have to have the tire roomed and remounted, but would be a low cost option to check out on one wheel.

I wanted to post to thank you for including pictures of your car and the TR250. I had not seen close up pictures before of your TR3. You did an outstanding job on the restoration including the quality of the body work and paint job. Thanks for sharing.

 

[tdskip]

Car look great Pat!

 

[6TTR3A]

You can buy radial tire tubes. Off Road Warehouse normally has them. Places like Discount Tire don't sell them but
if you take your own they will install them, at least here in San Diego they do. If you go that route, be sure there
are no inspection stickers on the inside wall of your tires. The tube is designed to flex against the tire.
The friction wears off the paper of the sticker, but the adhesive backing grabs the tube & holds it in place
until a pinhole appears in the tube. Result: Flat tire. I had four flats on new tires/tubes in 1000 miles
on a long drive. No one knew why until a "geezer" explained what was happening. It was a "new"
problem because the tire inspectors had used caulk entries on the tire before stickers.
99% of the tires were tubeless so the problem didn't become obvious.
Frank