April 20, 2007

Changing Tires On My Roto Tiller

Ok - I got this great 8 HP Roto Tiller from Craigslist. The carb and fuel line were all gunked up and the tires were flat. I repaired it and inflated the tires but they didn't last long. They were pretty dry and cracked so I decided to replace them They held air long enough to test the tiller. When I went to use it several months later I decided to changed them as they had severe cracks.

Click Any Image for a larger, more detailed view.

I ordered the replacements from Ebay. These are 480 X 400-8 tractor tires. They cost $16 each and $12 shipping. As you can see the old tires were shot. Since I got the Tiller for free I just didn't see the need to pay someone over $100 to mount the tires.

In order to remove the tire you need to break the bead ( where the tire mounts firmly to the rim ). To break the bead you need to remove the valve stem. Any auto parts store will have a valve stem kit with new valve stems and the tool to remove them.

Once the valve stem is removed it's time to break the bead. I broke the bead by jumping up and down on the tire. One side was a real challenge and took about 5 minutes. Persistence pays off. You can see in the photo below that the bead is now broken ( you can see the inner part of the rim ).

Removing the tire from the rim is tough without special tools but can be accomplished in about 5 minutes. I used a pry bar and a large flat head screwdriver. It's like changing a bicycle tire but the tire is a lot thicker and harder to persuade. You start by placing one tool between the tire and rim, prying it over the rim, and then work your way around with the second tool. Once you make it to the half way point the tire will pop off.

Below you see the opposite side still on the rim.

Because this is a relatively small tire the rim can be pushed out at this point because you can get good leverage on it. Hold one side down with your knee and push on the rim. It'll pop out. If not, try the pry bar technique.

Here's the rim - all nice and popped out... Because the Roto Tiller had been sitting outside a long time there was lots of debris inside the rim along with a little rust. Now, to be fair, it probably a better idea in the long run to replace the rims but I'm just going to clean them out. I mean what's the point in buying $200 worth of parts for a free tiller?

I used a wire brush and knock off the large part of rust and gunk from the inner sides of the rim. I also washed it down with a scouring pad and soapy water.

Ok - all nice and clean. Ready to mount the new tire. I've applied a liberal amount of soapy water ( dish washing liquid ). This helps the tire pop around the rim.

Start by placing the rim against something to keep it in place. I used the back of my pickup truck which also makes a nice bench. The more soap the easier it is to force the tire on. I just had to pry near the center in this case and the tire jumped onto the rim.

Here I'm pushing on the remaining section with the screwdriver.

Getting the bead to sit can be difficult. Because tires sit in stacks you'll often get one that's compressed and doesn't seem to fit the rim. No amount of air can get this tire to seat.

Actually I though I invented this but did a Google search and discovered they actually make a tool for this purpose. It's called a Tire Bead Strap. I just used on of those ratchet tie downs you can buy anywhere for a buck or two. I just happened to have some in my garage. The idea is to force down on the center of the tire to have the sides mate with the rim.

Once you got the strap cranked down enough you pump air in - lot's of air. I set my little compressor on full ( 100 lbs ). You'll hear a little pop with these small tires as the bead seats.

Remove the strap - it's be difficult as it's got a lot of pressure on it, then bounce the tire a few time to make sure the bead is set. You should be able to let all the air out without the bead breaking.

Inflate the tires to normal pressure and you're done. Both tires took about 30 minutes total. Hope this helped someone save a few bucks!

Disclaimer: These articles are not warranted, not tested, and not suggested and are merely a documentation of things I've repaired myself.

Links to other pages I've found about Tire repair:

http://www.jpmagazine.com/techarticles/wheels/154_0704_jeep_tire_bead_re_seating/