Steering broke YM186D

[California]

First real problem I've ever had, running Yanmars since 2003: My steering went crunch on the little YM186d and quit responding. The shaft is now an inch too high coming out of the top of the steering column. There is absolutely no left turn action at all. Steering right has some minor influence on the direction it wants to go. I had to put my wife on the tractor and walk alongside, forcing the direction the wheels were pointed using a long pole, to get back to the barn.

Has anyone overhauled a steering box? Advice?

I have the Shop Manual to describe dis-assembly. Pulling the cowl looks like a nuisance.

Comments?

Thanks in advance!

 

[Soundguy]

likely a thrust bearing or bushing died.

I've rebuilt just about every manual steering box on all my tractors.. not much mor ethan sectors and worm gears.. sometimes a recirculating ballnut.. that and bushings, bearings and seals..


soundguy

 

[Gary Sweat]

First real problem I've ever had, running Yanmars since 2003: My steering went crunch on the little YM186d and quit responding. The shaft is now an inch too high coming out of the top of the steering column. There is absolutely no left turn action at all. Steering right has some minor influence on the direction it wants to go. I had to put my wife on the tractor and walk alongside, forcing the direction the wheels were pointed using a long pole, to get back to the barn.

Has anyone overhauled a steering box? Advice?

I have the Shop Manual to describe dis-assembly. Pulling the cowl looks like a nuisance.

Comments?

Thanks in advance!

You may have broken the ball nut or a tooth off the sector shaft. Not hard to replace the parts but can be a little difficult getting the arm off the sector shaft. You have to use a stout wheel puller and patience. I did a complete rebuild of mine. Easier to work on if you take the whole steering box out of the tractor but it can be done by just sliding the steering shaft up off the box. Just makes it a little cramped to work on if you leave it in the tractor. Hoyes video covers the steps pretty good.

 

[California]

Thanks Chris. It's good to hear from someone who has BTDT. This doesn't sound so scary if it's just the $15 upper and lower bearings. I hope ...


And Gary, thanks for your experience, and your reference to the Hoye steering rebuild video. I'll go watch it now.

 

[winston1]

Hoye also has these printed instructions. Yanmar Tractor Steering Shaft Fix

 

[Soundguy]

Thanks Chris. It's good to hear from someone who has BTDT. This doesn't sound so scary if it's just the $15 upper and lower bearings. I hope ...


And Gary, thanks for your experience, and your reference to the Hoye steering rebuild video. I'll go watch it now.

PS I don't like to dink with.. bt manual boxes are generally easy and self evident.

you'll be fine as long as you can get parts.

soundguy

 

[284 International]

California, I'm sorry to hear about your breakage. I'm interested to see the teardown and repair though, as well as the failure analysis. It seems as if it's an improbable event. You don't have a loader or anything like that to stress the steering box. It seems odd. I've never broken a steering box in anything before, although I've steered a couple Jeeps and 3 full sized pickups out of places after breaking Pitman arms (or the associated balljoints) with the long branch and bravery method....:laughing:

 

[Soundguy]

lack of lube, then resulting thrust bearing failure is common on the boxes I've fixed. these are of course, symptoms of a different problem.. leaky sector seals.. etc.

soundguy

 

[California]

Next question - how the heck do I dis-assemble the column shift (Powershift) linkage to pull the dashboard and cowl? With it still in place and the rest of the cowl loose, there was a little wiggle room to get the steering column out. But it will be impossible to push the steering column back through the dash grommet at such an angle to re assemble it. That column shift assembly appears to run through a tube with linkages welded on *both* ends.

I took the steering column and steering box out as separate pieces. But according to the manual the cowl has to be removed to install the rebuilt column intact. These parts also need to be removed to install the steering box bolts beneath the gas tank.

Has someone done this? The service manual covers only the floor-shift version and says the cowl, and the fuel tank and its mount, have to be removed. But with the column shift linkage a single massive welded assembly, I can't see how to remove it.

 

[California]

Failure mode: just what Soundguy said. (He is one of the original gurus here, co-founder of this TBN Yanmar Forum in fact, for those of you haven't yet met him).

There was bad rust all down the steering shaft. Then nothing left of the upper shaft bearing where the steering shaft enters the box, just a fragment of its ball cage. This explains how the steering wheel became higher.

The bearing at the bottom of the steering shaft had a few balls left in its cage. When I bought the tractor I noticed the steering wheel dragged on the top of the steering column sleeve, and added a washer under the steering wheel. So the lower bearing must have been bad for a while to let the steering wheel settle down like that.

Also, the end of the Pitman shaft that engages the adjuster doesn't look like I expected. I thought it should have a groove that let the adjuster pull against it. Is that correct? It's end had one tab standing without such a groove, and apparently broken at its outer end, and the other tab apparently snapped off. What should the adjustment end of the Pitman arm look like? Does the adjuster only push against it?