I've a tire whose valve is leaking.
Is there any way to fix the valve or do I have to replace the tire?
You could try Slime. Available wherever fine mountain bikes are sold.
If it's the inflation needle type and leaking from the center hole, you could try what I did when that happened:
Take an old inflation needle (plastic ones work best) and fill it with glue. Once the glue sets, insert it all the way into the valve and leave it there like a stopper.
The valve is probably pretty standard. Take the wheel/tyre assembly off of the cat-trax and bring it to any place that does tyre repair. The valve will cost a couple of dollars, and probably another couple of dollars to dismount, and re-mount the tyre on the wheel. Have them replace it with a standard schrader valve type valve. Don't use slime. It makes a mess if you ever do have to replace the tyre.
The stopper idea sounds good. I did take it to two tire places and both said no dice. It did pump up fine, but once the needle came out, it deflated. Thanks.
Is the valve like a standard car valve? I'll look at mine next time I'm there - but if it is, just take it to a bike store and they should be able to replace the inner workings of the valve for a couple of bucks. If you have a friend who is a cyclist, he probably has the tool to do this.
You mentioned a needle, so I assume it is the basketball/football style fill valve. Take a plastic golf ball marker and trim the head to the size of the valve. (3/16" or so). Fill the tire with a ball hand pump and pop in the golf marker. I have this in all of my roleez wheels and they don't leak anymore. You can take them out in the spring for a top up and put back in.