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Topic: Bendix Air Cruise Control (Read 2140 times) previous topic - next topic

Re: Bendix Air Cruise Control

Reply #25
Gary,

I would say you are correct - throttle will operate totally independent of cruise control.  The DC-4 shuttle valve is completely mechanical in operation - so it will pass through the pressure from the throttle valve whether the cruise control is dead or alive.  Another nice feature of the system!

I haven't studied the throttle valve (gas pedal) setup, yet.  Need to do that.  I assume the throttle valve must have a built-in "exhaust" function, so that line pressure is reduced as you let up on the gas pedal.  Otherwise the CC-5 Air Cylinder would not be able to retract (return to idle position) when you were operating on "Air Throttle" only.
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: Bendix Air Cruise Control

Reply #26
I just looked for my comments on this issue but it must have been on another thread. I am relating to my suggestion of removing-one at a time- and cleaning all the valves in this system as you could have one "hanging up" so to speak as Red Tractor did. I cleaned each one up and made sure they worked correctly.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Bendix Air Cruise Control

Reply #27
Thanks to chuck,john, and gary for the great input.  It amazes me that both systems(manual and cruise) work perfectly except for this one situation(full throttle cruise).  Chuck, is your dc-4 value mounted at the bendix cruise control or some where else?  I believe mine is just to the right of the ca-1 module.  I will have to double check on that.
Pat/Blue Angel
1995 U240 36ft
MC# 16511
Build# 4653

Re: Bendix Air Cruise Control

Reply #28
My DC-4 is mounted directly above the Bendix "brain", and below the CC-5 cylinder.  See photo below.  I think yours is in the same place.

Also just something interesting I noticed in this photo: the Bendix box has lettering on it that says "U280 E14".  Done at the factory, I assume.  That is the same notation found on my factory Air System schematic (which I posted earlier in this thread). 
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: Bendix Air Cruise Control

Reply #29
The only real drawback is the fact (as we all know) that when you first start up the coach you do not have throttle control until air pressure gets around 50-60 psig.
I always wondered why I had no throttle control on initial start up, thought it was a engine temp safety thing.

Roland
1993 U280 4341
2010 Jeep Liberty
The Pied Pipers

Re: Bendix Air Cruise Control

Reply #30
Good Morning Chuck,
  Your cruise control board looks like mine.  Here's my pic. I am stumped.  I am beginning to wonder if there could be some other type of issue other than mechanically stuck.  Everything works fine, but....
I have included a pic of the other end of the throttle cable.  I wonder if there is some way this stuff could get stuck????

Thanks again for all the help.  I am going to Colorado on the 31st.  so today i am going to fill up on propane.  I will use the cruise and all functions of it.  All take offs will be full throttle. Updates after propane run!!

Pat,
Pat/Blue Angel
1995 U240 36ft
MC# 16511
Build# 4653

Re: Bendix Air Cruise Control

Reply #31
Roland,

Actually, I may have been overly pessimistic in my comment about throttle control at startup.  I was actually thinking about MY coach and how it acts.  Apparently yours works the same way.  Some owners may experience a different behavior.  The air supply for the throttle comes off a common line between the "FRONT" tank and the "REAR" tank.  If all the one-way valves, protection valves and control valves in the air system are sealing perfectly, then the air pressure in those tanks could hold up for a LONG time after the engine is shut down.  If that were the case, throttle control would be available immediately after the engine is started.  I work toward the day this will be true on my coach!

(I amended my original comment to refer only to my personal experience)
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: Bendix Air Cruise Control

Reply #32
Pat,

"I wonder if there is some way this stuff could get stuck????"

"Sticking Linkage" at the end of the cables was my very first guess back at the beginning of this thread.  But since it never happens when you apply full throttle with the foot pedal, I think we have pretty much eliminated that possibility.

"All take offs will be full throttle."

You must get terrible fuel mileage!


Good luck on your trip to Colorado.  If it was me, I would avoid using Cruise Control on the big uphill runs, until you get this problem sorted out!
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: Bendix Air Cruise Control

Reply #33
Chuck, I agree with everything you said, except for the fact about my gas mileage.  I get 10MPG towing or not, I drive 60MPH.  I will only use the cruise on level ground and only overpasses on the coming trip.

On the startup throttle control, mine always starts and rpms go up to about 8-9 hundred, then falls off to 7 hundred and stays there.  My MH holds air for a day or two.

Pat,
Pat/Blue Angel
1995 U240 36ft
MC# 16511
Build# 4653

Re: Bendix Air Cruise Control

Reply #34
 On the 240 I too noticed no throttle control till air built up, but agree if you have air in tank it should operate normally.
Pat, maybe I missed this earlier but I do not remember seeing in your posts (after cleaning cc-5etc) that you actually tried to replicate the problem and that it did actually still hung up. I am still sure that you have the same problem we had for 3000 miles (sticking fast idle). I even tied a piece of rope on throttle cable and ran it thru coach so I could pull on it when needed to slow engine--but that did not help! It only stopped doing it after ALL valves/cylinder and linkage, plus throttle pedal cleanup happened. It never came back even on the 700 km trip to Alberta, so I know it fixed it.
Again, have you taken apart all the valving etc and done the resistance checks in manual. PLus spray lube all over the linkage at pump and some release oil on the pivot shaft.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Bendix Air Cruise Control

Reply #35
Great information from you all! I will be doing some of maintance issues you all have suggested once we get home. Yesterday my Bendix began acting up....it will set but then after about a minute it pulses up and down. It will not hold a steady speed. At first I thought it was a road quality issue, nope. I guess a lube a clean out is in order. It's gonna be a long drive to MI from NY tomorrow lol
Jeff
Jeff & Carrie
2023 Geneva 31VA
1989 Grand Villa 36' ORED "The Button Pusher" - GONE 🥺

Re: Bendix Air Cruise Control

Reply #36
to JohnH: I have not tried to reproduce the full throttle hang(I am a  little scared to).  I have only cleaned the CC-5 air cylinder, checked  the throttle cable for binding/sticking.  I have driven the MH 2 times since cleaning.  Both times:  full throttle take offs, used all cruise functions(level ground except for overpasses on loop).  All cruise functions work perfectly,  throttle control works perfectly, manual throttle control is perfect.  All of the previous cruise throttle hangs have been by mistake/forgetting the cruise is on until it is to late to turn it off.  After all hangs were gotten to release by using the manual throttle pedal going from wide open to idle(service brake application & turning cruise off had not effect) , the cruise works fine.

Jeff: I think finding solutions to problems is very easy after you have defined and understand the problem.  Then I think you should only change/repair/replace one thing at a time.  If you use the shotgun method of trouble shooting, you may not know what the fix was, you may also not understand the problem like you thought you did.  I also think you should not fix it, if it is not broken.

I am still looking/working on the problem.  I wish I could think of a way to test my issue without killing me or other folks on the road.

Pat,
Pat/Blue Angel
1995 U240 36ft
MC# 16511
Build# 4653

Re: Bendix Air Cruise Control

Reply #37
Yesterday my Bendix began acting up....it will set but then after about a minute it pulses up and down. It will not hold a steady speed.
Jeff,

If you have not already done so, I recommend reading through the entire Bendix manual (link below).  You will get a good understanding of the system, and be more confident when you attempt repairs.  On page 22, there is a discussion about "Surging", which sounds to me like what you are describing.  Good Luck!

http://www.wanderlodgeownersgroup.com/downloads/BendixCruiseCtlManual_Parts.pdf
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: Bendix Air Cruise Control

Reply #38
Thank you Chuck...this is my bedtime reading material tonight. Since I'm off work tomorrow after the dentist I'm going to start this project.
Jeff & Carrie
2023 Geneva 31VA
1989 Grand Villa 36' ORED "The Button Pusher" - GONE 🥺