Broken RC-1603 tiller

[bish_oz]

I was tilling on the weekend when my tiller decided to break down. After unbolting the plate where the PTO shaft goes into, I could see that the chain has broken. Although I can use a screw driver to fish out the chain, there doesn't seem to be any side access panels that can be simply removed to allow me to easily replace the chain, unless I completely pull it all apart.

This tiller is very heavy and I don't have engine cranes or anything like it to lift it up to work on it.

Has anyone any experience/advice on replacing a chain in this or similar model Yanmar tiller?

My guess is I'm going to have to raise the tiller on some blocks allowing the tines to freely move. Working through the small access port (where the PTO plate bolts to), pull the old chain out. Once the chain is fixed/replaced, I will need to feed it down, hope it catches on the bottom drive cog and turn the tines and hope it loops around and back up so I can grab it and then close the chain. Sounds like fiddly work to me...

 

[California]

I know nothing about those tillers so take this for what its worth ...

If you have to fish the chain through as you described, it might help to tip the tiller forward to where the chain drops in freely, turn the tines to engage the chain on the sprocket, then roll the tiller over upside down to bring the tip of the chain back out by gravity as you turn the tines to feed it through.

Some photos might help us visualize how this thing is put together.

Good luck!

 

[bish_oz]

Thanks California,

Notes from todays effort...

I pulled the chain out today. Looking closely at it revealed that it was missing a whole link and a bit. Presuming that it was still in the gear housing, perhaps buried in the inch of grease cake that lines the interior, I poured in degreaser and waited 10 minutes for it to work. Tipping the tiller upside down, I flushed out the housing with a hose. Only 2 little chunks of chain fell out, which meant there was still chain bits missing. I repeated this procedure a number of times looking for more of the missing chain without success.

Calling over the next door neighbor for advice (he is a car mechanic), we agreed that it might be best to get access to the bottom of the gear housing, which would involve removing the bearings plate, and/or tine shaft. This way I could look for the missing chain, and perhaps replace the shot bearings.

First I removed the end cap (which has 2 tines) on one of the tine shalf. It revealed bolt head(?) which looked like a thread which had been welded to a bolt... Weird. Was it meant to be unbolted? I tried, but it didn't budge.

So I then decided to try removing the side plate on the gear housing, which I presume would hold the bearings. I got the bolts out, but the plate would only separate from the main housing a couple of mil. I also noticed that the axle had stopped freely turning. Pushing the plate back allowed the axle to freely turn again.

So I then removed the cap on the other shaft. It revealed a bolt similar to the other side. So using a hammer and a socket wrench, I discovered that I could remove the end bolt which holds the tine shaft. It was a long bolt, the length of the tine shaft.

Filled with a new level of hope that I was on the right track, I then tried to remove the shaft. I tried pulling it off, hitting it with a hammer, then a sledge hammer, shaking it violently , using a screw driver to force open the bearing plate... Nothing. I then tried to remove the bolt on the other side. It wouldn't budge. So I had a beer and looked at it for half-an-hour.

With the sun fast disappearing, I put everything back together. All I had to show for today's effort was sunburn and completely destroying the bearings (perhaps I shouldn't have used the hammer!?!).

Unfortunately the tiller doesn't even make a good looking garden ornament...

 

[ctjstr]

Sure hope you get this all figured out, other then as yard art...
I just picked up one of these pretty cheap. All the right stuff seems to turn, but havn't had the chance to use it. Sure would be nice if someone else did the guinea pig thing on repairs before I break mine. (o.k...sorry)

Good luck!!!