Hey Guys! Of course I'm new here, I just bought my first bus... GM 4107. The POs had planned on installing power steering but didn't get to it. I have a power steering box, I'm assuming used from another bus. I will post pictures below. I have also been hearing of Shepard? Any guidance would be very much appreciated! Thanks in advance ;)
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Hopefully you've looked under your bus at the steering box setup and seen that the steering box is mounted to the front axle. To me, your pictured steering box is for a frame mounted like used in a truck.
Sheppard made the big power steering box for direct mounting to the front axle. When I changed mine, the 90 degree miter box was 1.5 to one for the air assist steering. I also changed the miter box to 1 to 1. Went from 9 turns to 3.5 turns lock to lock and from having to use two hands to finger tip steering at all speeds. Make sure you have a power steering pump that puts out over 2000psi. Good Luck, TomC
Doesn't the 4107 have power steering now and the PO was just going to upgrade the steering box ? I wouldn't waste my time installing that box go with the integral power steering
Quote from: luvrbus on November 20, 2013, 02:35:04 PM... go with the integral power steering
OK, what is "integral power steering"???
Bruce Integral steering has a manual steering mechanism,a hydraulic control valve,and a hydraulic cylinder in the steering housing
good luck
Quote from: Oonrahnjay on November 20, 2013, 04:23:13 PM
OK, what is "integral power steering"?
Simple answer:
If the steering gearbox has hydraulic hoses running to it, that's integral.
If there are no hydraulic lines to the box, but there are to a big slave cylinder attached to the steering drag link, then you've got manual steering with power assist.
Bryan's 4107 should have power assist, GM didn't start installing Sheppard integral until '72/'73.
FWIW & HTH. . .
;)
Ok I meant to add Ross that unit he has is always a problem even on GM's that is the same steering sector used GM transits from the 70's IMO if you go with a Shepard use the D or M series
Look on tag if that is a 492 AP it's not a bad sector set on 1750 psi
okay, so maybe the PO didn't install this unit because it wasn't the correct one? Would anyone mind giving me some guidance in what steps I need to take to acquire the necessary parts to install it. I wouldn't be installing it myself, I would have a mechanic do that, but I could go searching for the parts that I need. When you say Sheppard Power Steering, is this a new unit that I can purchase or do I have to find one out of an old bus (sorry I'm a newbie lol).
it's my understanding that I have to have the 1. Power Steering Box 2. Pump 3. Hydraulic Lines... is this correct? Thanks guys! ;)
Not sure if this applies to your bus or not but I know on my fishbowl adding the Sheppard power steering box as you have pictured.
Requires a part you have not listed, it is the Radius Rod that is bent to go around the power steering box you just mounted to the front axle.
I have a complete extra kit that I don't have the radius rod for...... When I was stripping the donor bus I didn't realise I needed it :(
the stock one doesn't work without the bend :(
The power assist pump is different than the integral pump you need the numbers off the steering sector and pump for the GM guys to help you fwiw all steering sectors are rated for the front axle weight some are adjustable with pressure and some are not
The GM guys like Chris, Wildbob and others can answer your questions if they have the numbers
good luck
Quote from: luvrbus on November 21, 2013, 11:24:23 AM
The power assist pump is different than the integral pump you need the numbers off the steering sector and pump for the GM guys to help you fwiw all steering sectors are rated for the front axle weight some are adjustable with pressure and some are not
The GM guys like Chris, Wildbob and others can answer your questions if they have the numbers
good luck
Thanks Luvrbus. Where would I find the numbers for the pump? I was under the impression that I had to buy a pump, but I may already have one? Also where exactly will I find the numbers on the steering sector? Again, I'm a newbie lol, thanks so much!
If I was wanting all the right parts I would call Luke @ US Coach in NJ someone here will have his number you get the price of the upgrade you maybe happy with what you have ::) You owning a GM Luke is going to be your best friend
Luke: 1-888-262-2434, M-F, 9-5 Eastern
Since you've mentioned that you'll have to have someone help you install PS (if you don't already have it), there's the Choo-Choo Express Garage not far from you on the GA side of Chattanooga. Several busnuts have had work done there, from routine maintenance to major engine work, all seem pleased.
147 Prater Rd
Rossville, GA 30741
(706) 891-1242
FWIW & HTH. . .
;)
Hey Bryan
Take a look at the bottom of this post for some pictures of the Sheppard power steering system I installed on my 4106. Um, you do not need to remove the axle to install.
http://www.busconversions.com/bbs/index.php?topic=7748.0 (http://www.busconversions.com/bbs/index.php?topic=7748.0)
Quote from: RJ on November 21, 2013, 05:52:06 PM
Luke: 1-888-262-2434, M-F, 9-5 Eastern
Since you've mentioned that you'll have to have someone help you install PS (if you don't already have it), there's the Choo-Choo Express Garage not far from you on the GA side of Chattanooga. Several busnuts have had work done there, from routine maintenance to major engine work, all seem pleased.
147 Prater Rd
Rossville, GA 30741
(706) 891-1242
FWIW & HTH. . .
;)
Funny thing, the PO I bought the bus from also gave me Luke's number. Must be a good contact to have :-) I will be calling Choo-Choo Express once I figure out what exactly I'm going to need. Thanks for both contacts!
Quote from: OneLapper on November 21, 2013, 07:23:28 PM
Hey Bryan
Take a look at the bottom of this post for some pictures of the Sheppard power steering system I installed on my 4106. Um, you do not need to remove the axle to install.
http://www.busconversions.com/bbs/index.php?topic=7748.0 (http://www.busconversions.com/bbs/index.php?topic=7748.0)
Checked out the pics! Wow! I noticed you talked about the play in your steering wheel. Mine has a LOT of play in it. Will that be fixed when installing PS?
Yep that is the bad point of the Sheppard gear there is no adjustment to take the slop out and they do get sloppy ,unlike the Ross that has a adjustment
The folks at Sheppard say a new Sheppard gear can have 2" of free play at the steering wheel and that is acceptable. Not to me. Ross made one 492 series axle mount gear that was used on the MCI 96A2, that's the best thing you could put on a GMC, but they are nearly impossible to find. I took an old Ross gear with a long sector shaft that mounted to the spring perch and a regular frame mount Ross gear and made an axle mount gear for my 4104. Most people are happy with their Sheppards, It's a very durable gear but the fact there is no free play adjustment can be a problem. Unfortunately the Sheppard is the only thing that's readily available. I have a Sheppard gear left over from a separate project that's one of the tighter ones I've seen, It's for sale.
Ken
I did like Kirby I took a Ross from a MCI 9 and made a bracket installed it on a 4104 and no problem the owner has been running it now for 10 years
Thanks guys! What are the best methods in searching for a Ross?
Probably a truck salvage yard. You might try Lewis Bus Lines in Augusta GA. Joey had a 96A2 gear several years ago but he wouldn't sell it to me. In a salvage yard the problem maybe a finding a gear with a long enough sector shaft that will get the pitman arm under the axle. Since you are changing things for the better try to find a 90 degree gear box from a later model transit bus. They have tapered roller bearings instead of brass bushings and you can flip the gears around if the steering gear you find is the wrong rotation.
Ken
He should take the bus to you Ken or somebody that done the change before it is not for the faint of heart or cheap ::)
We had the Sheppard installed in our 4104. It had virtually NO play in the steering wheel. You need to check for play in the steering shaft u-joints, slip joint, tie rod ends, king pins, drag link ends, and bevel gears at bottom of column where the drive shaft to steering gear connects. Oh, and change those bevel gears to 1 to 1 when changing over.
Some of them are tight, Uncle Ned has a good one. Sometimes the owner has just become accustom to the free play and doesn't realize how badly the coach drives. That was my case. Two tests, go to a big empty parking lot, turn the wheel either to the left or right stop, accelerate with no hands on the wheel it should return to the straight ahead position. The more it doesn't the worse it's going to drive. The next test requires a dial indicator and maybe a helper, make a pointer from a wire hanger, tape it to the dash and point it to the steering wheel. Use a dial indicator to measure when the tire begins to move when turning the steering wheel one direction then the other. Using the pointer mark the steering wheel when tire movement begins in both directions, that distance is the free play. 1/8" or less is good, the greater the number, the worse it's going to drive. My advice is don't do these tests if you are happy with the way your bus drives.
Ken
I have been to 3 world fairs saw almost everything but never saw a Sheppard steering on GM bus that wasn't sloppy and loose
Like Ken I guess if you don't know the difference and are happy it works I drove a 4905 for 300 miles it was a constant battle for me after years of owning and driving a Eagle with Ross steering I am not saying they are not out there I just haven't came across one yet
Bryan
I have heard of this elusive Ross axle mounted steering gear, but have never actually seen one. If you want to add power steering to your bus, you'll most likely have to use the Sheppard system.
If you're bus has the optional power-assist steering, you'll be ahead of the game as you can use the existing pump with the Sheppard gear by changing out the pressure relief valve and most of the plumbing will be in place.
I see your email address in your profile. I'll send you a copy of a GM/Sheppard conversion manual that should prove helpful in your search. Let me know if you receive it.
Ive got .pdf versions of the 4107 maintenance and parts manuals, if you need them.
Bob
Here is a upgraded Sheppard system that works on a GM and not hard to install
Model 492-AP-1-2 sector but you have to change the pump to a 4 gpm with operating psi of 1750 # you can find those on a 1992 Orion transit bus axle mounted fwiw Kirby 4104 has a Ross on his GM
If he hasn't sold the bus for scrap I may know where a Sheppard steering system is at I have a friend that bought a Orion for the DDEC engine and electronic transmission for 2500 bucks at a Vegas sale I'll check that out for you
Clifford,
Yes, the Vickers pump used with the booster cylinder on the 4107 is rated at 4 gallons per minute with the pressure restricted to 1000psi. You can boost the pressure to 1500psi, which is the pressure used on the 4905 with the 492-AP-1 gear. The part number for that relief valve is 11G-9-2, available from MCI for about $50.
I wonder if the increased pressure makes the gear work better.
Bob
What is the difference between the AP-1 and the AP-1-2 sector Bob we replaced the AP-1 with the AP-1-2 and had to replace the pump
Too many Sheppard setups on GM's have never had the caster reset to a few degrees of positive for better tracking. Negative caster makes it easier to steer, but has a greater tendency to wander. Also many never go through the effort to eliminate the play from loose or worn components. Also check Shepard for play with engine running.
Any steering gear with the high point adjustment can have the free play adjusted and agree on the positice caster, would recommend about 2.5 degree Pos, for handling with firm feel. there is lots more to good steering than just caster and toe in. Proper drag link, tie rod, radius rod bushings, king pins and a good steering gear box will bring it all together nicely. If you do a nice / correct job on the front end, you will not need nor want a safety steering spring setup, they are used to cover up the slop in the system.
dave M
Somewhere, I think on the Sheppard website, I read that the old types had about an inch or two normal slack - which mine does and it is a very old model. I decided to live with it after I found out the price of an update!
I do need to check the rest of the linkage for slack though, I expect the shafts, U-joints and slip joints are all loose a bit which adds up.
Hey guys! As you may have seen on my other post, I haven't been on the forum in a couple days so I'm catching up. You guys have been so kind to help me as a newbie. Thank you for your PMs and emails! We are remodeling the inside right now which is taking a lot of my time. This part is pretty easy for me. But the mechanical end of it, I'm a total NEWBIE (in ALL CAPS lol), but I'm definitely becoming a bus nut. I can feel it haha. This is my first experience with one!
Anyway, with all that being said. A lot of this about power steering is kind of going over my head. Although I do want to understand it, I won't be doing the install myself. So I'm wondering if I just need to take it to someone that knows like a few shops or individuals and show them what I have and let them assess the bus and what it needs to have power steering and also less play in the steering wheel. I know some of you have spoke of power assist. I'm not sure if I have that or not either. As you can see I'm in NorthEast Georgia, do you guys have any recommendations of people that could look at it and give me an estimate of what I need, and costs of parts, and installing? Thank you guys!
How far is the Nashville area from you ? Ken (Hardheadken here) may have time to do it for you if not he will know of someone you can trust
Clifford,
To answer your question, I don't know the difference between a AP-1 and an AP-1-2. First I heard of that number was when you posted it here.
I do know that early 4922 used bushings and later ones used roller bearings. Maybe that's the difference?
Bob
Another person to check with if Ken doesn't have time to do It.
Gene Russell at Russells diesel.
Millsprings NC
Don't have his number handy but someone will check in.
He did Boomer's coach for him
I'm about 5 hours from Nashville, 2 hours from MillSprings (I was actually in MillSprings not to long ago)
Gene is close to you an should be able to do the job. He put a Ross chassis mount gear on Boomer's Silversides and his. A chassis mount would be the best thing for any bus that an axle mount gear but it would require a major re-engineering. Probably not worth it, but if I had to do over again that's probably what I would do. The Sliversides already has a chassis mount gear so it's not such a big job on that bus.
Just about everything has been covered in this thread except this. I mentioned how to check for return to center. Here's the usual overlooked cause when it doesn't, but don't overlook king pins and ball joints. Most power steering gears only require 6 inch pounds of force to activate the internal valving which provides the hydraulic assist. Remove the input shaft from the steering gear. You'll have to put something in the input shaft with 1/4 or 3/8 female drive (I think I used a socket that was the correct OD) it doesn't have be really tight you're only measuring inch pounds. Now measure the torque required to rotate the steering wheel. If it's much more than 6 inch pounds then the caster can't do it's job because the excess drag results in steering gear holding the tires pointed some direction other than straight (it's the same thing as the driver holding the steering wheel not straight ahead). Then you correct by steering the other direction, then it's pointed the other direction and the process repeats. Eventually you become accustom to this and learn not to over correct too much, but you're still fighting it all the time. Again, if you want to know, let someone else drive and watch them, let's say your wife (that's how I found out how terrible my coach drove but I had learned to put up with it). The steering geometry can't make the vehicle track straight driving down the highway and not require constant corrections if the steering gear won't let it.
It's nearly impossible to get below 6 inch pounds on a coach with an axle mount gear. All the u joints slip yokes, the 90 degree gear box and bulk head bearing contribute to the problem. I used a 90 degree gearbox from a transit bus, light weight synthetic oil in it and synthetic grease everywhere else. About 6 inch pounds was as good as I could get it. A chassis mount gear does not have all those parts, that's why a chassis mount gear will just about always drive better than a an axle mount gear.
Try the return to center test on what you drive every day and try it on your coach. The steering wheel probably won't return to the exact center but the closer the better. Going slow across the parking lot steer to the left or right let go of the steering wheel, it should return to near center. If it keeps heading the direction you turned it with no hands on the wheel that's why it's so hard to drive in a gusting side wind and why it darts around so bad in the truck pavement ruts.
Ken
Ken, thanks so much for the info!
I think my best bet is going to be to call some shops like Gene at "Russells Diesel" and "Choo Choo Express". Thru out this thread I have learned that some think the Shepard is sloppy and some and have had good experiences with it. I've also learned that there are adjustments that can be made to help the slop. Some of these adjustments I would not know how to do, but would both of these shops know the best ways to not only install the power steering but make it as tight as possible? I guess since I'm new at this, I don't know exactly who to trust.
And last question, does this mean that parts I originally posted on this post will not work? Thanks so much! :)
Ken is so correct about the darting. Just remember, wonder and weave is loose, worn parts, while dart and diving is too tight as in rust, lack of lube.
From the old school (Bear Front End Alignment days)
Bad steering makes for unhappy long trip.
Dave M
Everyone with power steering on a bus needs to add to their arsenal Chart Your Way To Easy Steering a manual by TRW while it is for the Ross it applies to all steering makes life so simple it is a free download from TRW JMO
? for the Sheppard users did any other highway coach manufacture ever use the Sheppard besides GM
Bryan,
Looking at the pictures, I think you have an axle mount gear. I don't think there's a method to determine how the gear will perform until you install it. You can clamp some pliers on the input shaft and get a rough ideal on the free play, remember that small free play will be multiplied by the steering wheel size and slop in the system. It will be a little different once installed and under load.
Ken
I have a chart that says 1/8 free play at the box will translate into 2+ inches on a 20" steering wheel fwiw for a 20" wheel the DOT gives 5-1/4 inches before red tagging how would you like 5-1/4 inches of play for 2000 miles not me lol I am guessing that would keep a driver alert and on his toes
Quote from: luvrbus on December 01, 2013, 04:54:58 AM
Everyone with power steering on a bus needs to add to their arsenal Chart Your Way To Easy Steering a manual by TRW while it is for the Ross it applies to all steering, makes life so simple, it is a free download from TRW. JMO.
http://trucksteering.trw.com/Service%20Manuals (http://trucksteering.trw.com/Service%20Manuals)
This one is the: Chart Your Way To Easy Steering a manual by TRW
http://trucksteering.trw.com/sites/trucksteering.trw.com/files/pdf/TRW1250.pdf (http://trucksteering.trw.com/sites/trucksteering.trw.com/files/pdf/TRW1250.pdf)