Transmission linkage issues

[Jessekarkiainen]

I have a 1972 MCI mc7 with a Eaton RTO9513 (13speed) transmission that refuses to shift due to 35ish feet of 50-year-old bent and loose linkage. I've been talking to someone who has removed the same transmission from his 89 eagle model 15. He has cables that shifted the transmission instead of linkage. My question is will his 33 ft long cables fit on my bus? What other components do I need to make this project complete? Are cables a reliable effective way of shifting? What do I call the apparatus that connects the cable to the transmission and what's the dealy Whopper that connects the stick shifter to the cable? And lastly is $400 a fair price for two 33 ft push pull cables and the shifter do hickey? I can pick up new Marine push pull cables between $100 to $150 but I have no idea how to shop for the chingaderas that go on either end of the shifter cable. Any information would be greatly appreciated, thank you

[buswarrior]

Beware, there are many adapted buses out there that the shift pattern is backwards.

The proper shift tower from a cab-over is needed to "turn it around" or teach yourself to shift backwards.

Have you evaluated your current set-up? A few fresh bushings and it might be lovely again, with less effort than dragging those cables through the bus?

Happy coaching!
Buswarrior

[Busted Knuckle]

I second BW on this!
First off WHO installed the 13 spd in your bus?
Second DID it ever shift right?
Third IF IT EVER DID, I'd think it would be better to do as BW suggests and fix the existing linkage by freeing, lubing or replacing all seized, worn, loose parts in the current set up.
Sometimes jumping overboard and swimming to a new ship is not always the best move in shark infested waters.
  BK 

[Coach_and_Crown_Guy]

There's no way that MC7 with factory linkages would ever shift the 3-rail (three linkages needed) RTO-9513. MCI used only 2 push-pull linkages to control the stock 4 speed transmission and required an electric solenoid/actuator to pull the transmission tower selector into the internal 3rd shift rail to catch the reverse gear. This is all so typical of the time and used also by GMC on all their manual shift buses. The only differences were the actual design and implementations of linkages going from the driver to the transmission tower. All were designed and built with 4-spd trans. The electric was needed to activate the third shift rail for reverse in the transmission.

Whoever installed that RTO in there HAD to have made some extensive modifications to the fore and aft linkage in order for the new transmission to use reverse and the actual 1st gear, If it even fit properly with the correct range of motion to effect the shifts since it's a much larger and longer transmission. If they hadn't done all that then the transmission would have required the use, STILL, of a reverse gear button and actuator. By the way, does yours work this way??? if so then the linkage hasn't been changed properly to accommodate the 13-spd. That transmission MUST have access to all three internal shift rails in order for it to function as designed.

All this would mean that some form of cheesy half-functional modification was made to the linkage to even make the new trans fit, (it's quite a bit longer and heavier) as well as other unknown mods to kinda make it work. All this kinda engineered stuff may be what is giving you the symptoms you're experiencing, it just isn't well thought out, or executed. And by the way, this usually causes the shift pattern to be mirrored and flipped around as noted above. It isn't the cab forward so much as the reversed engine coming in from behind the rear axle and the shift linkages not moving and selecting the correct internal shift rails. Well known issue with all rear engine, behind the drive axle, mounted T-Drive vehicles.

Lucky for you there is an extremely easy and properly engineered fix for all your troubles. Easy, not necessarily cheapo. Check out www.cablecraft.com and go into the PRODUCTS tab and toward the bottom you'll see the manual transmission shift assemblies. These are fully engineered high quality capable OEM products, or, of course retrofits as in your case. They would replace the existing shift tower by the driver from the floor up, and have a matching assembly that bolts to the transmission tower. It only uses two push-pull cables between them and offers the option of flipping the pattern around to whatever you require. They can restore the normal and natural shift pattern as first built by MCI. With the addition of course for the extra third slot for reverse and the real first gear. You can fake it with a 13spd by sacrificing the real first gear which is very low and not needed on a bus, and then having the electrical solenoid and button pick the transmission 3rd rail for reverse. This could work and wouldn't require huge amounts of mods to be done on the existing shift linkages. I'm thinking this may be what's in place with your MC7 as you received it. This is your cleanest and easiest solution and will give you total peace of mind as well as providing you with the full mechanical function of your 13spd transmission.

Many many years ago I had to replace the shift linkage and bellcrank parts on the Scenicruiser Charter bus I owned and operated. At that time I had fabricated a pair of CableCraft push-pull cables and simply replaced the almost 40ft of rods and bellcranks with the cables. I left the original GMC front shift tower and underfloor shift bars, by securing the new cables to the existing parts. The same at the rear on the transmission shift tower levers. Simply attached the new cables. Very easy actually and worked like a charm.

After the modifications were complete I found that the effort to shift the transmission was reduced so much I could literally shift the thing with two fingers and also started shifting it without the clutch due to the extreme precision I could control the transmission and ease of moving the shift lever. No lost motion at all and no effort due to the internal Teflon lining in the cables. No more of the exaggerated motions required to impart inertia to the shift linkage in order to exact the correct motion at the transmission to affect a smooth, or any in most cases, gear selection. All that wear and tear through the years added immense lost motion and made shifting GMC and MCI's a thing the driver had to learn to overcome.... or else. Ever had a GMC get locked in a gear due to the shift linkage losing motion and not pulling it out of gear before trying for the next gear, always between 2nd and 3rd as you move from the right shift bar to the left bar under the floor??? That's a thrill a minute. A hammer on the linkage at the transmission will usually fix it, until it hangs up again that is. 

The CableCraft solution is totally superior and when used with their own front shift and rear shift assemblies will give an unbelievable tight and factory new feel to the overall shifting experience.
They will handle any three rail transmission known like the Fuller RR's and any other brand as well.

You appear to also be asking if you can use the removed cables from that Eagle. My simple answer is. probably NOT. The lengths and cable end hardware are very specific to each installation. You can try seeing if they are long enough to do what you need to do, but it's a given that they will need modification work done by companies equipped to build and work on these kinds of cables, Check around, they aren't hard to find. Also as I said before if there are only two cables there will be no way for you to pick the reverse gear without an electric solenoid, and the shift pattern will remain reversed and mirrored. Also you won't have any idea how good the cables he took out will be. Like why did he take them out??? They can be damaged or of an inferior and/or non-heavy duty enough design. REAL and proper heavy duty push-pull cables will be engineered to be durable and provide the minimum of resistance to movement offering a true feel for the operator. Mine were lined with Teflon and were incredibly smooth and friction free. There's no real way you can expect to just buy someones take out cables and expect it to work on your different brand of bus. Not possible. You are facing a complete custom job from start to finish and no way around it. IF, that is, you can't fix what's in there already. Don't spend money on any used or take out stuff, very bad idea. Your bus is unique for all kinds of reasons and will require your total attention to creating a solution that works for you and your MC7.

Your solution is obvious and off the shelf available and reliable. Check it out. You may still get lucky as noted above if you can find and adjust/repair whatever is causing your current trouble.
But the real long term fix would be to consider something like the CableCraft solution. That's all I would ever consider for any of my own vehicles. Remember, this is not a hobby for the cost adverse among us. The risks/costs for on-the-road failures increase as we try to save money on critical systems and components. Engine and control systems are what I consider critical items.

[chessie4905]

I happen to have a new one I bought years ago to install a Roadranger in a ACF Brill. Called a remote manual shifter. Consists of a master installed by driver and a slave installed on top cover of transmission in place of shifter. This setup and two proper length cables is all that is needed. One cable controls for and aft of shifter and other cable controls side to side. All gears are available, and one cover can be reversed for different shift motion. Works on any Roadranger. Very well made with sintered? Iron gears and heavy bronze bushings. Never used it, as I sold the Brill before the Roadranger installation.

[Jessekarkiainen]

Thank you everybody for your input. But a special thanks to coach and crown guy, it looks like you've been there done that. Your information has been very valuable.
As far as if the transmission ever worked properly, I'm not sure. There's road grime on the bolts so I imagine it was driving down the road at one point but the fabricated hydraulic clutch engagement
was so far off it would have never worked, I had to remove and redo the clutch engagement unit, actuator? After I redid the clutch engagement it was a long struggle just to get it into gear and when I did the bus wanted to go backwards when I thought I was going in a forward gear. Eventually I got it going forward and tried to put it on a trailer, I had to back up to realign and she went back but then got stuck in between gears. She went forward in second gear and reverse in reverse so I don't think the pattern was flipped but I do think it never fully disengaged from reverse. I fully intend on going with cables. The cables this guy wants to sell me look like they were a legitimate kit possibly from cablecraft, I'll call them and figure out what's going on. The linkage just has too many issues the shift tower is loose the linkage is physically bent and where the linkage goes into the transmission is bound. I could probably fix it but I would imagine I'd run into more issues given the age and complexity. I really want to try and make this 13 speed work mainly cuz that's what's already in it and I was hoping I would get relatively good fuel mileage. Anyone got an idea of what MPGs would look like with a mc7 8v71t and a 13 speed.?

Chessie4905 you wouldn't happen to still have the remote manual shifter would you?

[Coach_and_Crown_Guy]

I happen to have a new one I bought years ago to install a Roadranger in a ACF Brill. Called a remote manual shifter. Consists of a master installed by driver and a slave installed on top cover of transmission in place of shifter. This setup and two proper length cables is all that is needed. One cable controls for and aft of shifter and other cable controls side to side. All gears are available, and one cover can be reversed for different shift motion. Works on any Roadranger. Very well made with sintered? Iron gears and heavy bronze bushings. Never used it, as I sold the Brill before the Roadranger installation.

Is that the one with the sector bevel gears in it? Kind of like whats in a rear end differential? I think those were what CableCraft had at the time 40 years ago and I almost bought a set myself until I realized I could fix my 'Cruiser with the simple two cable fix and use the existing shift levers already on the transmission. Sintered gears indeed. I've actually been looking around today to find if they are still available and made the same way today. But it appears they have been dropped for the current designs where they use simple levers to provide the needed motions. As long as it all works the same and gives the ability to change the shift patterns around and allow for front and rear cable entries, which they seem to still do today, then it's all good. Yours is a nice piece of tech history then where they were evolving to what is available and used today.

[Jessekarkiainen]

This is a picture of the shifter part of the setup I'm thinking of buying. Does it look familiar?

[Coach_and_Crown_Guy]

OK. It sounds like you never were able to drive it yet. As I suspected, that's the way you got it and have never really been able to drive it properly. You're correct in figuring that a good quality cable solution is the best for you. Chessie has both the front, with the driver shift lever, and the rear unit that bolts onto the top of the transmission. They are a matched pair and were designed to work together. These two units work perfectly and with the proper (must be exact) length cable, and end hardware to match, it will be an extremely sanitary fix and should be easy to implement. Running the two cables through the bus shouldn't be that big a nightmare. Pay close attention to the front mounted unit on the floor and where it needs to be located so it doesn't hit the driver seat when it rises straight up. Remember the MCI's had it located just under the seat edge and the lever was bent away from the driver slightly. I really liked this arrangement and it felt good when driving, very cab-over tractor like, along with keeping it out of the way when getting in and out of the seat. Down by your thigh instead of reaching out and up like many other buses. This solution will give you an almost factory new and very solid reliable fix. It's definitely the only way to go in order to do it right.

I may be way wrong but that thing has the look of something that originally was designed for a Truck Tractor, not any kind of Bus. That long support piece screams to me it was mounted on a Tractor structure behind the shift lever, and not a flat floored bus. If it was made to fit and worked in an Eagle, then good for them, but I wouldn't trust it to be able to be made to fit into your MCI. You don't have that kind of room under the floor for this.

I wouldn't take any chances on ANY used take out gear because there's no real guarantee it can be made to work or even FIT in YOUR bus. The only solution is to get Chessie's New Old Stock never installed CableCraft matched pair system components and then take the time to look over your bus both front and rear and do the measuring for the cables and have them made up custom for you at one of the companies that do this stuff. I'd stick to CableCraft cables since they are real heavy duty and probably still have the Teflon or equivalent friction reducing design.

There are structures below the floor by the driver you don't know about yet that will make any device you plan on installing there very troublesome below the floor. Not much room and even structural parts in the way. That thing you pictured looks large and has parts spread out all over. I don't think you'll be able to get it in the MC7. If that came out of an Eagle then it's for sure going to be problematic to make it fit into an MC7. Take the time and check it all out and measure the spaces involved carefully before you commit to buying anything. But I'm real sure Chessie's parts will fit and can be made to work just fine. They're not large at all and very compact, and if I remember correctly they mount simply, directly to the flat floor with a nice square box extending below the floor in the same footprint and the two actuating levers just below that on the sides.
One thing you're not aware of, and that piece you pictured doesn't have, is the required cable end clamps that hold the outer cable in place at a precise and adjustable for motion position. This is Key in getting the motion you need as it allows the inner cable to move back and forth over the full range needed. These cable clamp brackets are all part of the units Chessie has and will be required if you use any kind of cable. the thing you pictured will only work with the normal fixed rod and bellcrank type of factory linkages used. You'd need to fabricate your own custom cable end brackets if you wanted to use that.

The CabelCraft units are a very neat and highly universal design intended for many applications. Check it out and I'm sure you'll see what I mean and will like it.

If that clutch is actually using a real hydraulic system, and not just an air assist cylinder, then that's a huge red flag regarding the cut and chop job that forced the RR in there in the first place. As far as i know there was never any hydraulic systems used, while an air-assist was a definite possibility. In fact MCI was famous for using LOTS of air cylinders to tension the belts for instance in the rear. They all tended to leak along with the plumbing, the valves, you name it. That's why all MCI's of that era couldn't hold any air for more than a couple hours after the engine was stopped.

I'm pretty sure that the clutch and bell housing were probably changed to accommodate that RR, which MAY have been required, I'm actually not a mechanic as some on here truly are, but the concept of the different size bell housings SAE1 SAE2 along with the very basic differences between a Pull versus a Push clutch are not at all unknown to me. I've dealt with them on several buses through the years. Get yourself an MCI repair and parts manual ASAP and read up on what was factory spec'd. Then you won't be blind-sided and surprised when you find any and all manner of custom re-engineering shoved into that bus. If done well, extensive modifications can be just fine, but, I think we all know, and have seen, way too many "Fixes" that haven't been, .... how shall I say this.... Worth a Crap!, and Nightmares lying in wait. Good luck.

[chessie4905]

Yes, that's how it looks inside. I'll  post some pictures.

[luvrbus]

Dave and Dennis @ Southern Oregon can give you some tips they installed the Road Ranger in several buses over the years ,the last one I recall was on Mel's Eagle behind a C-15 Cat engine ,Bob Gilbert would be help to he owns one behind a 8v71