Steering issue continued

[Lin]

I am continuing the question re: my sluggish steering.  The mechanic says he does not believe it is the alignment because of the even tire wear.  Since I have brought it inside getting ready for a trip, I have not gotten a second opinion from an alignment shop, but have noticed that the steering has rough spots even when moving the wheel back and forth 30 degrees while standing still.  The mechanic seems sure that the problem is bearings and/or u-joints in the steering column.  He says that those things are greased when they leave the factory, but not after, so it is reasonable for them to wear out in 40 plus years.  I noticed that there are four holes with screw-in plastic plugs at the upper bend in the steering column.  Are these for grease or some sort of adjustment?  They are not big enough to fit my grease gun in, but I thought that maybe they are supposed be packed with grease.  Even if the bearings are bad, a little grease might help.  Has anyone had to rebuild or change the steering column?  We leave Sunday (the plan anyway) and will have to deal with the fix later on.

[NJT 5573]

Lin, I don't know what you are driving, but it almost sounds like the steering box mounts are loose or rusted out. You need to have someone wiggle the steering wheel while you check each component until you find this problem.

Steering boxes need grease, as do kingpins.

I have also seen steering box bolts loosen and allow a box to flop around.

Based on what you have stated you are out of service. Get it fixed, then drive it.

[Lin]

NJT,
     This is my MC-5a.  I had the front end checked, but he might have missed something.  I greased all the zerts I could find on the front end even though they appeared to have a lot already.  Are there some things to grease that do not have zerts? The steering box is full of oil and looks much newer than anything else around.  The mechanic speculates that the steering box was replaced in an attempt to deal with the same problem, but it was the wrong answer.  My complaint is that I seem to have to compensate the steering constantly.  At first, I thought it was my inexperience with the system, but after a while I decided I have adapted to every vehicle I have ever driven quickly, so there must be something wrong.  The mechanic, who is not a bus mechanic but excellent on trucks, drove it and immediately said that the problem was that the steering wheel was lightly hanging up and therefore did not true itself when let loose.  I had noticed that the wheel had to be manually brought back to center after a turn.  It seems to me to be a little better at higher speeds, but still a nuisance.  Do you think that his conclusion that it is in the steering column is wrong?  It is really hard to tell by feel where it is catching, but it does seem to be real close to the steering wheel.  That, of course, could just be my prejudiced imagination.  I guess if no one has heard of steering column bearings wearing out before, it makes it less likely.  What are those capped access holes in the steering column for anyway?

[Stan]

I converted and drove a 5A for more than 50k miles so I have some random thoughts. Your power steering system is prone to slack in the valving on the bottom of the steering box. Brand of tire and tire pressure on the front can have a significant effect with wander. I got much better steering with bias tires than radial. With the front end off the ground, you should be able to feel a pronounced tighter spot on the steering box when the wheels are straight ahead ( I would expect your alignment mechanic checked this). If the steering box is to tight on the high spot  it is hard to get it to stop on center when you correct for wander.

The steering column has lots of bearings that could be bad. IIRC the plastic cover can be removed by taking the screws out of the flange at the floor and at the top. The caps may cove the top screws!  I don't remember any zerks on the U joint or bearings.

Ironically. I have never driven any power steering (car, pickup, truck or bus) that steered as well going down the road as a good non power steering.

[HighTechRedneck]

Your mechanic is there and is a professional, I am neither.  And the rough spots in the steering would seem to indicate a mechanical problem.  But even if there is a mechanical problem causing rough spots, I would still suspect that the camber is near zero.  Camber and toe problems will quickly effect tire wear.  But lack of positive caster doesn't have much impact on tire wear.  Negative caster can cause cupping.  But near neutral caster will cause giddy steering and a lack of automatic return to center.

[JackConrad]

Have you checked the toe-in?  0 toe-in can cause the bus to wander. I think specs call for 1/16"-1/8" toe-in.  Jack

[NJT 5573]

Lin, steering column bearings do wear out.  Kenworth used bushings for many years, I don't know about MCI. I spray lots of WD or a similar product, (Fluid Film is heavy spray lanolin), into the hole with the horn button off. Sounds like you have manual steering is this correct? Raising the front of my Eagles took the wander out. Is there a way to change your air bag ride height on the steer axle? My 77 is manual and my 89 is power. The power drove badly and the combination that fixed it was Lucas Power Steering Additive along with the height adjustment. I have a slight toe issue with my tag that causes rear steer.  If the tag is not real close to 1/8 toe in you can chase the steer forever and not cure the problem. (Don't think you have a tag, but rear steer can also be an issue with a drive axle). Get some string out and see where everything is pointed.

Manual boxes have a lash adjustment, if you have checked the front axle with 2 people, one moving the steering wheel back and forth and one person looking at each component and no part has slop on either side, try backing the lash off half a turn as that will cause a box to hang like you describe.

I think the "positive" camber gains as you raise the air bags. I'm not familiar with your adjustment mechanism but most just need a small steel rod lengthended. I have used flat iron and drilled several holes for adjustment to get driveline angles close enough to reduce driveline vibration on trucks. If you try this I'd go a couple inches depending on how its setting now. Is it nose down?

[roger dolan]

   On my 4106 when I put in new king pins I found that under the king pins was a thurst type bearing that supports the weight of the bus. In my case thrbearing was full of dirt and rust and would hardly move. When I replaced the king pins they came with a new thrust bearing and it steered much better. Also some times power steering pump pressure will cause a problem with catching in the steering.
                 
                                                Roger 4106

[Sojourner]

As what Roger posted....If you can jack up under I-beam in the middle (front axle) high enough to get both wheels off the surface, then try turning steering wheel to see if it turn freely in straight position as well toward left & right. If it is free all over then probably is what Roger posted. If it is only binding or dragging in straight position, then your steering box is too tight (binding). If it dragging or binding from L to R or vice versa, then it need to look for front wheel to be freely turn either L to R or R to L by moving by hands in either 9 or 3 'o'clock position to look for very little free movement. Whatever you do look for part of steering system that tight. Your steering wheel rotation should have a free play of 1/8" before steering linkage move. Unless you have power steering which is about 1 1/2" to 2" free play.

Do you have slave power steering cylinder on drag link? 

About if you have or not an OEM steering column...take photos of it to post so we may be able to help you better still.

FWIW

Sojourn for Christ, Jerry

[Lin]

Thanks for all the input on this.  I will start trying the different suggestions with the easiest first.  Also will try to get second mechanics opinion.  I liked the one about the box being a little tight, and that would be easy to fix.  The mechanic says that the wheel has good "snap back" at the locks and believes that a tight box adjustment would have effected that.  I don't know.  One of these things will get to it.  I did spray some WD40 into the steering column center hole and even pumped grease into the access holes that I mentioned.  The plan is to be on the road tomorrow (if that fails, then Monday).  I will see if there is any improvement then.  If not, it will be a day of rather annoying driving, but we will make it to fight another day.

[Fredward]

Lin,
My 5a has new King Pins and tie rod. I can't say that I've experienced the feeling you mention. But it definitely wanders. The way the power steering works is based on sensing pressure on the drag link. Its a reactive system. You have to stay on it all the time. I've heard an "integral" steering box can replace the OEM and improve the experience.

Before replacing the king pins and tie rod it was downright scary to drive. Every bump in the road sent the coach off in another direction. You never knew which way it was going to head.

But be sure there is nothing broken before you take her out on the road.

Fred

[Lin]

Thanks Fred, this does not seem to have that same loss of control problem; just constant need for compensation.  I had installed integral power steering on my other bus, and it is great to steer.  Regardless of how this turns out, I will probably do the same on this bus. 

[Stan]

Further to my previous comment on tires. Most highways are rutted and when your front wheels are in the rut, any movement will start an oscillation of trying to climb out of the rut. The more flex in the sidewalls of the tires (low pressure or soft wall radials) agravates the situation. Driving with Michelins wore me out but bias tires with 100 PSI ran OK.

Note that this is a separate thing from something sticking and applies to the drag link assisted steering on MCI.

[buswarrior]

Why would you go to the veterinarian if you have a sore throat?

Take that bus to a real bus mechanic, who is properly equipped to investigate and who knows about these things. Ideally, he is/was the go-to guy in a larger fleet. Lots of mechanics claim to know, and don't, and will jump right in, taking your time and money.

Truck mechanics are way out of their league when it comes to the suspension under these buses, and does not have the experience to know where to look first to straighten out the nuances of getting the bus to run "right". Experience means seeing these things day in day out, and watching the ravages of time effect the chassis over and over. Where has the truck mechanic had to deal with all those radius rods, a wheel base that long, and a chassis that is that old and with that kind of mileage and wear on it?

It is well worth planning a pilgrimage half way across the continent, east or west, to one of the masters with the 40 years plus of wrench turning background and who still welcome old equipment. Others will chime in with their testimonials. Luke's place, US Coach, across the line from Philadelphia PA in Berlin NJ, is the East Coast holy ground. 1-888-262-2434 and he or one of the staff will talk to you on the telephone. West coasters, chime in with your holiest sites.

I'm not fond of paying for some other guy's education, entertainment or misrepresentation.

happy coaching!
buswarrior

[Lin]

Buswarrior,
     You are not doubt right about finding a bus mechanic.  I have had trouble finding own locally, but now that I will have a new locally, maybe I that will change.  I have been in regular contact with Luke, who by the way, has moved to Vineland, NJ with the same phone number.  I have been getting a lot of parts and advise from him.  Stupidly enough, I have forgotten to ask him about this one.  As a west coaster, I would be interested in learning about good bus-conversion-friendly mechanics on this side.   Using a truck mechanic is fine for some things but could have its limitations.  However, I will also point out that an excellent mechanic can sometimes go a long way in making up for a lack of specific experience by being just plain good.  While, on the other hand, I had a supposedly experienced bus mechanic look at this bus before I bought it, and he missed some serious problems.

By the way, the vet always gives me a biscuit.