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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Alan N on April 09, 2016, 12:27:13 PM

Title: Air Lines for Transmission.
Post by: Alan N on April 09, 2016, 12:27:13 PM
I am in the process of replacing the 5 speed manual transmission in my bus with a 10 speed (rto 610).
The bus is a 35 foot rear engine Gillig skoolie.
My question is about the air lines to shift between high and low range. On a truck these lines are very small diameter but also very short.
Do I need to run larger air lines or will the small stuff work?
I am considering using 1/4 inch tube just to minimize the possibility of obstruction in the longer run of line.
Any thoughts, comments, suggestions?
Thanks.
Alan
Title: Re: Air Lines for Transmission.
Post by: Bob Gilbert on April 09, 2016, 01:48:12 PM
The small line work fine on my Eagle 5 10 spd.
Title: Re: Air Lines for Transmission.
Post by: kevink1955 on April 09, 2016, 03:04:36 PM
Not knowing how fast the air must dump to make it shift I would be afraid of the larger  tubing holding more air and slowing shifts. Only a theory on my part as I have no idea how an air shifter works.
Title: Re: Air Lines for Transmission.
Post by: azdieselman on April 09, 2016, 03:08:27 PM
You might consider using both!

The 1/8" or 5/32" spaghetti line can be difficult to clamp securely.

You can run the range lines inside of the 1/4" to give it protection and make it easier to clamp or zip tie.

It's commonly available in Black, Red and White to make the connections less confusing.
Title: Re: Air Lines for Transmission.
Post by: chessie4905 on April 09, 2016, 05:12:57 PM
Instead, I'd run two lines of the 1/8 inch if you have concerns. it's pretty durable and zip ties work fine. An RTO 613 would be really nice.
Title: Re: Air Lines for Transmission.
Post by: buswarrior on April 10, 2016, 08:37:05 AM
You need to stay with the small line.

Pnuematics will slow down as the volume to be moved is increased.

Bigger line means more volume to fill it.

A small signal line will move faster than a bigger one.

Speed is what you need, not volume.

Happy coaching!
buswarrior
Title: Re: Air Lines for Transmission.
Post by: HB of CJ on April 10, 2016, 01:36:54 PM
If memory serves, the air lines from the RTO910 to the range shifter in my old Crown were very tiny.  Yep ... perhaps a velocity and time thing rather than volume.

Remember to preselect for about 2-3 seconds before doing a range shift.  This gives the air lines time to do their work preloading the tranny range shift synckros

Just a note that the RT613 does not split the high side.  Basically it is a straight 10 speed with 3 extra low gears for heavy slow pulling requiring deep reduction.

I do not remember which gear/clutch housing is needed for the RTO610.  Probably a #3 or perhaps a #2 housing.  Overdrive 10th will increase your road speed 25%.

Be sure to find and lube up all the grease zerts on that single shift pipe or shaft.  This will make shifting your cool Roadranger a 2-3 pound effort moving about 2-3 inches.

Can just the correct tranny make that much difference?  Oh yeah.  You will be very happy with the RTO610.  A gear for every need and some you will not use.  :)
Title: Re: Air Lines for Transmission.
Post by: chessie4905 on April 10, 2016, 02:46:26 PM
 rt913 and rt9513 were 9 speeds with splitter in top range 4 gears. They did make rt908LL work some super low lower gears. I built up a RTOO9513 for use in my 1948 ACF Brill behind a 6v92. With a 4:11 rear axle it would have been nice cruising at interstate speeds. Btw...http://hankstruckforum.com/htforum/index.php?topic=1013.0 (http://hankstruckforum.com/htforum/index.php?topic=1013.0)
Title: Re: Air Lines for Transmission.
Post by: HB of CJ on April 10, 2016, 03:27:58 PM
My mistake and thank you.  Meant to say RT613.  Corrected.  Years ago in 1969 the Fuller salesman showed us the small factory booklets on the various 910 models.

The last batch of brand new 1968 Crown Supercoach school buses had the RTO910.  72 mph in 10th at 2100 rpm.  4.10 gears.  10x20 tires.  We thought that was neat.

Whopping 220 hp 743 Cummins engines with Jake Brakes. No interior A/C which was considered not needed in Bakersfield CA in the summer?  Kern High School District.

The gear ratios were listed for the various models of 910 transmissions.  The available factory, (rare) RTOO910 listed a 1.00 8th, .79 9th and a .66 10th.  Very cool.
Title: Re: Air Lines for Transmission.
Post by: Alan N on April 10, 2016, 03:52:13 PM
Thanks for the thoughts and the advice. I appreciate hearing from those who have experience with these things.
The thought that smaller is faster makes sense.
I am sure I won't need 10 gears. I just wanted overdrive and my throw out bearing needs replacing so now is the time.
Thanks again.
Alan
Title: Re: Air Lines for Transmission.
Post by: TomC on April 10, 2016, 09:19:42 PM
Does your transmission have the X shifter? Otherwise you'll be shifting the transmission backwards-which is confusing. Good Luck, TomC
Title: Re: Air Lines for Transmission.
Post by: chessie4905 on April 11, 2016, 04:24:39 AM
I have the info manual for many of their transmissions. Acquired them when building up my trans. Still have the remote manual shifter units that use two Morse cables that use for shifting. If the front of his transmission points to the rear, the shift pattern would be different than the other way also.
Title: Re: Air Lines for Transmission.
Post by: HB of CJ on April 11, 2016, 11:20:17 AM
About the only thing I can think of to mess up this thread is to consider your drive shaft angularity.  The RTO 610 is a big flat long tranny.  Heavy.  360 lbs+-.  I had one in my living room for a couple of years.  Became a coffee table.  Took strong help to move it to the strong dining room table where it got overhauled. 

Your drive shaft will be shorter.  Will the U-joints still work?  If memory serves (always suspect!) Fuller had different tranny shifter tops that corrected the reverse shift pattern for a pusher "T" drive configuration.  Different tranny U-joint end yokes are available to match up your existing U-joint size.  Fun!  :)

You probably have 1510 or 1610 U Joints.  Just a guess.  What kind of engine do you have?  I could be wrong with your U Joint size.  Remember the RTO 610 will happily take 800 foot pounds of torque in the top 3 gears.  If your tranny is undersized, just learn to keep your foot out of the engine until 8th gear.  Then have fun. 
Title: Re: Air Lines for Transmission.
Post by: Alan N on April 11, 2016, 08:07:47 PM
Quote from: TomC on April 10, 2016, 09:19:42 PM
Does your transmission have the X shifter? Otherwise you'll be shifting the transmission backwards-which is confusing. Good Luck, TomC


I have been shifting it backwards for years. It can get confusing.
When I get messed up and have trouble finding a gear my children laugh and say "Dad you're in truck driver mode again".
I am sure more gears will bring more opportunity for this. :)
I think this transmission will have the old style shift pattern with 4th & 5th / 9th & 10th reversed.
It will be fun.
I'm waiting for my clutch now. I want to see how it works. :)
Title: Re: Air Lines for Transmission.
Post by: Alan N on April 11, 2016, 08:16:03 PM
Quote from: HB of CJ on April 11, 2016, 11:20:17 AM
About the only thing I can think of to mess up this thread is to consider your drive shaft angularity.  The RTO 610 is a big flat long tranny.  Heavy.  360 lbs+-.  I had one in my living room for a couple of years.  Became a coffee table.  Took strong help to move it to the strong dining room table where it got overhauled. 

Your drive shaft will be shorter.  Will the U-joints still work?  If memory serves (always suspect!) Fuller had different tranny shifter tops that corrected the reverse shift pattern for a pusher "T" drive configuration.  Different tranny U-joint end yokes are available to match up your existing U-joint size.  Fun!  :)

You probably have 1510 or 1610 U Joints.  Just a guess.  What kind of engine do you have?  I could be wrong with your U Joint size.  Remember the RTO 610 will happily take 800 foot pounds of torque in the top 3 gears.  If your tranny is undersized, just learn to keep your foot out of the engine until 8th gear.  Then have fun. 


It's kinda amazing but this transmission is the same length as my old 5 speed.
I think that the drive shaft will bolt right up.
Something else surely won't work but I think the drive shaft will. :)
Title: Re: Air Lines for Transmission.
Post by: Alan N on April 11, 2016, 08:31:19 PM
HB.
My engine is a 3208T.
I managed to find a tranny top that is just right, except it's backwards.
So a little cutting here a little welding there and everything should work.
The clutch may require some Norwegian engineering, we will see.