Cause of a slow leak?

[Oz_Kioti]

My Kioti RX8030 (76hp to give you an idea of the size) is just over two years old now, and has just developed a slow leak in one of the rear tyres - maybe one psi per day (and it's only got 13psi to start with!)

The R1 tyre and rim look perfectly seated, and I thoroughly cleaned the area around the valve and gave it the old soapy water trick, but no bubbles there. Photo shows stem type.

So any ideas on the cause, or is it just "one of those things?"

 

[seville009]

Based on my experience with car tires, a slow undetectable leak like you describe really can only be fixed by reseating the tire and replacing the valve.

Much more of a pain to accomplish with a big tractor tire, of course.

I foam filled all my tires years ago; that’s always an option if you never want to worry about leaks again. Costly, but worth it over the long term.

 

[oldnslo]

Can you spray soapy water around the bead to check for leak? Also spray the complete tire to see if you possibly have a nail or thorn puncture in the tire face.

 

[CobyRupert]

Don’t forget to check for leaks through the valve core too.
And as other say, check around bead and whole tires for any punctures.
Also, I’d put maximum air pressure in the tire when doing soap bubble test. Get as much to leak as possible….although this could backfire if it’s a bead seal leak and more pressure tightens the bead up.

 

[Richard]

Not my big tractor thankfully.... but my riding mower never held air....even from week to week it would go flat. I finally did the soapy water and to cut to the chase, the air was bubbling out THROUGH the tire itself. Might have been tiny pinpricks if/as I drove over some prickly something or another (NOT thorns mind you) There were NO evident thorns, nails, screws anything in them. It was a slow bubbling of the soapy solution and it covered a wide area.

If I had to draw an analogy, it would be like a pair of socks that are wearing thin on the bottom. The bottom might still be intact (tire looked good) BUT, they were thin enough that if you went from walking on carpet to tile, you could immediately tell where the worn spots are on your foot because of the temperature change.

I finally replaced them two years ago and have had zero issues since. (shrugs shoulders)

I say soap them up and find the leak, go accordingly.

 

[FordnMassey]

Hi,
Leaks at the bead can be tested for by laying the wheel down on a flat surface and filling the crevice between the tyre and rim with water. Flip and repeat.
I have had new tyres fail to seal.
Pain to have to take it off the tractor, but if you need it serviced it's off for transport.
Consider a tube.

 

[4570Man]

Grab a spray bottle or a water bottle with a hole poked in the lid will work. Mix up some soapy water and spray around the bead and the valve stem. If you haven’t found the leak at that point keep spraying the whole tire.

 

[Oz_Kioti]

Thanks for the replies guys - much appreciated. Give me a couple days and I'll report back.

 

[Oz_Kioti]

Hi all, thanks to your suggestions, I soapy-water checked the bead, and found the leak! A close inspection revealed some tiny woody fragments wedged in the gap, but not visible from a distance. Lost nearly 2 psi overnight.

The local (20km / 12 miles away) tyre service is coming down early next week to sort it. Break the bead and see what's what, but don't need to remove the wheel from the tractor, so that simplifies matters somewhat.