B steering column

[harrybarbon]

Brocky

The finished pictures were at Castlemaine truck show Nov 2016, soon after Ian's team completed the truck. The unpainted bare cab was around 2013, kind of lost track of time, our Mack took about 17 years, from start to finish,  time seemed to pass us by and being a custom job, the end was nothing like what we originally started. That was same for Ian's Princess Diana, Diamond T - not time wise, but what was planned and what Ian completed. When you guys were at Ian's after Alice Springs and then Tony Champion's,  Ian's team then put in a big effort to get it finished for Castlemaine, always a mad rush to finish, but it happened with lots of goodwill and passion. 

We are going to Gatton, Queensland with our Mack for the 100 years of Mack in Australia - 28 & 29 September 2019, should be a big popular Doggie show.

 

[Hobert62]

I’ve been messaging with davehummel on this topic because he has done a similar conversion to his, but Here is a pic of my current progress.     I don’t think This steering box would work on a truck with an original axle.   There wouldn’t be enough room to turn to the right very far.    

[davehummell]

I mounted mine out closer to the bumper and that gave me the room. the different steering pump I am now using has a valve with three hoses going off it and now the steering is better more feel at road speed.

[Vladislav]

I never put my hands on a truck power steering gear so far but I have a couple of points to put in.

1st. Once patiently stydieing description of design of Mercedes G-class steering gear which is too close to what was used on some Russian trucks of mid 60's I found interesting nuance about pressures. The matter was when you steered you activated some pressure in the box which was applied to a piston which moves Pitman arm shaft by some way to turn wheels. It's clear the harder the wheels to move at the time the more pressure you needed. Using that effect that pressure was also provided to some another part (piston or its area?) in the box so when you turn the steering wheel you have to put force against it. Telling different words the resistence of the steering wheel you felt as a "road feeling" was in fact not any force reacted from the road but a force simulated in the steering gearbox specially for the feeling. Sure there was a corellation but those forces were not the same thing. And taking that to account the matter of "blind" steering with some power setup could be in that very wrong design of the unit.

2nd. Once I looked over design of early KrAZ truck powersteering which was an air assist I noted it had a power cylinder at the right of the truck and a drag link with a valve assembly at the left attached to a mechanical gear. Pretty sure I saw something similar on Western RL-model Mack but with hydraulic cylinder not air. Nevermind. The function of the system is you turn the wheel in the cab you move the drag link and there are control valves which are spring loaded by some way. If you drive down a highway or steer on ice just a few resistance goes from front wheels so valve springs don't compress enough to open valves. This means the power cylinder doesn't get any pressure so doesn't effect wheels to steer at all. And you steer just like (and in fact by) mechanical gear. As greater resistace to steer the road gives you the more force you have to apply to the sterring wheel. At certain point the force gets to the level of the valve spring to compress so valve opens supplying oil to the power cylinder and it helps. As long as you continue steering or even doing it faster the greater pressure gets to the assistance. If you stop sterring the valve spring looses application, depresses and closes the valve.

What's interesting to us in that is an integrated power steering gear also has valves iside. And also has springs in those valves. Othervise it just couldn't figure when to start to assist. Mercedes G-model gear has them I know. So way to correct a power steering feeling is to play with the valve spring hardness. And not with fluid pressure or volume.

Worth to admitt a man should be careful tuning a power steering. Since if you put settings wrong your wheels could start turning themself at some time. And they wouldn't mind you're standing parked or doing 60MPH down a highway.

[Hobert62]

I agree vlad.    When it comes to mixing parts one must be careful.   My front axle is modern freightliner,  my pump and  steering box came off the same truck also modern freightliner which had the same 8.3 c series Cummins in that I’m also switching to this winter.       So I’m theory my steering should feel just like driving a mid 2000 freightliner fl70 or fl80 down the road.    

[davehummell]

Quote

 

I now have a pump that was on a mack firetruck the steering box came off a mack firetruck and the front axle is the one that was on my b

[Freightrain]

Vlad, power assist was popular in the 60's even with cars.  The drag link had a control spool in it that controlled a cylinder to help steer.  The Air o Matic in trucks was similar using air.  I have it on my truck, as a simplier way to add power steering without all the fabrication work.  It has its downfalls, but I say better then nothing.  My unit was in good shape so I hope to get many years out of it.

Like this conversation, even hydraulic power steering can have problems too.

[davehummell]

Ford trucks used a power steering setup that had two hydraulic cylinders on the truck so did a lot of farm equipment it was the change from true manual to an internal hydro steering box that came later. john deere had a setup on there garden tractors on the order of the drag length cylinder controlling pressure one way or the other. Back an air steering truck down a curvy road and tell me you love it.

[Vladislav]

18 hours ago, Freightrain said:

Vlad, power assist was popular in the 60's even with cars.  The drag link had a control spool in it that controlled a cylinder to help steer.  The Air o Matic in trucks was similar using air.  I have it on my truck, as a simplier way to add power steering without all the fabrication work.  It has its downfalls, but I say better then nothing.  My unit was in good shape so I hope to get many years out of it.

Like this conversation, even hydraulic power steering can have problems too.

Larry, please explain me one thing. Do you have the Air o Matic in operation all the time when you drive or switch it on only when you need it such as parking lot maneuvering and so on?

[Freightrain]

I did put a flip valve on the dash as others had mentioned doing to be able to shut it off.  I have turned it off a couple times to see how it steers on the road.  I've left it on for the most part now.  The drag link does have a touch more slop due to the valving and I don't like the heavy, sloppy feel with it off.

In all I have no complaints. It only gets twitchy going around sweeping bends where it sometimes reacts funny as the torque valve gets random input from working the wheel keeping the truck in line.

[Hobert62]

I got my column all mounted and I’m happy with the wheel placement.  It’s very comfortable from driver seat.    Now  my question is.    What is this bell shaped piece on top of the column?   Can it be removed and if so how?     If I can remove it I will be able to mount my turn signal switch and trolly valve higher up.   

[Hobert62]

Sorry had phone held the wrong way when taking pictures I guess. 

[Freightrain]

My guess is the wheel would have to come off, then that cone would be able to be unbolted.  I've changed similar units on cars/pickups before when converting to stick shift and not wanting the automatic shifter collar on there anymore.

Might not be too pretty looking with it off? 

[Hobert62]

I really don’t know what it is.  I’m guessing just decoration.     It it be nice to move the blinker that much further up though 

[Hobert62]

[Rob]

It is called the "Mast Jacket Collar". It houses the upper column rotary bearing supporting the steering shaft the wheel mounts to, the spring button the electric horn current runs through, and of course the automatic canceling turn signal switch assembly. It is a die cast unit. You can remove it and fashion a support for a roller bearing as the steering shaft needs supported on this end and use a stainless "wrap" originating from a polished "Torq-Tite" exhaust clamp for a decorative look.

Citing the column is originally from a truck without a column mounted shift handle there is no shifter handle originally incorporated and it should be devoid of any holes on the rt. side. The left side hole can be "filled" with something decorative to your liking but if me, I would look to retain the automatic canceling turn signals the column was built for but that is personal preference.

[Hobert62]

I got 2 columns when I got.   I decided to use this one due to the 18” wheel, other has a 20”.   They where both from mr garbage trucks.   I took the extra apart and Larry was right.   Very ugly exposed shaft and spacers.     After further sitting on my garage chair I realized they also had 900 series (non canceling) turn signal switches.  Same as my B but they have dimmer switch.  I was able to switch the clamp and bracket to my already wired switch.   It raised the switch and moved it forward.   

[Rob]

The "900" series was a very common turn signal switch through the years. Some like the later variant with the headlamp dimmer incorporated into the switch and some still prefer the button on the floor. Personal preference there but if you already had the "newer" style, it's quite simple to string new and additional wiring in the truck.

[Hobert62]

I removed my heater assembly which cleared out some space so the floor dimmer is fine with me.        I will save these other switches for probably forever though.   Now I just have to do some figuring where to cut the hole in the firewall and what boot I’m gonna use.   

[Hobert62]

[Rob]

What is this? A crack in your cowl or pillar:

[Rob]

Inner tube sections with an interference fit to tubing, rods, and linkage sandwiched between the floorpan, or firewall and a piece of plastic makes for a good weather seal in penetrations too.

[Hobert62]

Idk what that is.   It’s just a small piece welded in from factory by the looks of it.    Kinda like an extra brace?     I’ve seen sever of them throughout the cab

[Rob]

good deal as it looked like a crack from your original photo posting. I don't remember seeing anything like that in mine but it is probably a floor stiffener so the vibration is transferred more through the cab than concentrated in one spot.