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Topic: Air Throttle (Read 495 times) previous topic - next topic

Air Throttle

I've just finished with the install of my air throttle and It came with a new Allison Throttle Position sensor that replaces the one in the King box. There is a slide mechanism that I can adjust that connects to the new throttle lever. The new lever also has the cable from the air controller and the King Cruise is connected to it as well which I still use for cruise function. So there are 3 points of connection on the new lever. The Allison shifts normal 1 thru 5 but in 5th gear running by foot I have to reach 70 to 72 mph for it to shift to 6.. Too fast. I can run it up to 60 by foot then engage the cruise and it will immediatly shift to 6th gear and works fine after that as far as downshifts go. Problem is driving by foot, change to cruise and shifts right away. To adjust the slide adjust on the TPS it effects my lower gear shifts as in hangs up in 2 or 3. The setting I'm at now is my best performance but still not just where it needs to be. I know this air throttle throws a curve to collective thoughts beyond usual but it is where I'm at. I've emailed JOR and he may have a thought but there just aren't any other adjustment points available. Works great otherwise. WOT anytime I choose just to fast in 5th gear for a foot driven change to 6th. Any thoughts? I'm fresh out of ideas.
Dub McBride 1996 270

Re: Air Throttle

Reply #1 –
What happens when you hit the mode button on the shift pad?

So the king cruise uses the new Allison throttle position sensor?

Please take a picture of this shift lever so we can understand it
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Air Throttle

Reply #2 –
Quote from: turbojack –
What happens when you hit the mode button on the shift pad?

So the king cruise uses the new Allison throttle position sensor?

Please take a picture of this shift lever so we can understand it
Ive given that thought and changed modes once. I think i will try another test run or two and change modes and focus on that for any changes.
Dub McBride 1996 270

Re: Air Throttle

Reply #3 –
Changing to econo mode made no difference in the 5th to 6th change. Odd that the second I engage cruise it immediatly will shift to 6th at the correct speed. Obviously it's something some people would live with but I'm not there with it. I want it to work as it should.
Dub McBride 1996 270

Re: Air Throttle

Reply #4 –
Should have titled this Allison shift but I didn't have this issue before changing to air throttle. Leave it to my complications being complicated by something else, never simple complications. In glancing over information I noticed phrases including reprogramming an Allison. Don't have a clue what goes on with that but I am on the hunt for options or option. Read on other forums where changing mode let it make its last shift. That was advised early here but in my case didn't effect the shift.
Dub McBride 1996 270

Re: Air Throttle

Reply #5 –
Hey Dub, what happens when you are running on cruise in 6th, say at about 60, and you turn your cruise off...does it downshift to 5th at that point?
Ralph
96 U270

Re: Air Throttle

Reply #6 –
I haven't tried that move Ralph but I can. If I did I don't recall.
Dub McBride 1996 270

Re: Air Throttle

Reply #7 –
Made a call to Stewart Stevenson In Longview Tx, they have a good Allison man there that I hope can give me a hint or two when he calls back. Pretty good about returning calls there so maybe I can make some headway. Learning more than I wanted to know but not enough to amount to anything.
Dub McBride 1996 270

Re: Air Throttle

Reply #8 –
Dub,

You've probably already seen this, but just in case, I previously posted the link below in a old Forum discussion on this (TPS) subject.  It is a thread I found over on the IRV2 forum.  Might contain some useful info?

Throttle Position Sensor MD3060 - iRV2 Forums

PS:  If you would like to change the "Topic" of this thread to something more appropriate, it is easy.  Just go up to your first post in the thread, click on the "MORE" button, then the "MODIFY" button.  In the edit window, make the change to the thread topic, then click "SAVE".
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Air Throttle

Reply #9 –
Thanks Chuck.
Dub McBride 1996 270

Re: Air Throttle

Reply #10 –
Here are pictures from Dub and note below

The one on left is TPS and right is fuel control from the air cylinder
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Air Throttle

Reply #11 –
This is what Dub sent me

Yes, the TPS is on the engine bay wall and the cable runs to the fuel shutoff bracket that mounts to the throttle lever. A group of 3 wires are disconnected from the King box and plugged into the new wall mounted TPS.

Dub, how is the cruise attached to the throttle?

In order for transmission to go in 6th gear as soon as cruise is turned on, what is happening then cruise is set?

In reading the other posts it seems that the transmission is thinking engine is close or at full throttle. Can tps be adjusted where full throttle is not moving tps  as far, making it thinking less throttle is being applied?
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Air Throttle

Reply #12 –
The wire from the King Cruise box is connected to the fuel lever. The lever has 3 points of contact 1. Cable from the air cylinder 2. Original cable from the King box for cruise 3 TPS for Allison that is mounted on the wall. The cruise function is still operable from the King box. JOR continued to use his vs buying a new one and he reports no issues. I adjusted the TPS linkage and the only difference it made was to make the lower gears not shift. Again I can be running at 60 in 5th gear and engage cruise and it will shift out right then where as if I continue to fuel it by foot it will wind out to 72 or more before shifting to 6th.I've tried manipulating the foot pedal at different speeds in 5th to help induce a shift but no luck.
Dub McBride 1996 270

Re: Air Throttle

Reply #13 –
I read Jor's manual with pictures.  I now have a better understanding.

Can you move the mounting for the tps cable down more, or if not can you loosen the fitting on the end of the cable more.  Wanting to make the tps use a different part of the sensor. You will need to recalibrate this after moving spot on cable.

On another note, we need to figure out what is causing the transmission to shift as soon as the cruise comes on.  Is the cable moving or ???

Until we get this figured out you can drive like I do and use the cruise as throttle. Once I get the coach up to about 45 mph. I speed up and slowing down with the cruise controls.

Why is the tps cable allowed to slide on the fuel lever? I think the connection between the tps and the fuel lever should  be solid.  As lever moves either way, the tps position is also moved.

Could the lever be binding and it is not when the cruise has control, thus the tps is in a different position when pressure is released from air throttle?


2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Air Throttle

Reply #14 –
I'm on cruise as soon as traffic and road lets me. I made the TPS bracket on the left as Allison failed to ship one with TPS. Thanks for the trouble of studying this system. I can and have moved the cable but the only change was messed up lower gear shifts. I'm not sure if it's slid as low as it will go or not. I'll get over in there when some soreness leaves.king cable must move when on cruise but what it does when not on,I can only speculate. Steve at King told John ORiely any flex that may occur on the cable would cause no issue.
Dub McBride 1996 270