air throttle problem

Topic: air throttle problem (Read 3437 times) previous topic - next topic

air throttle problem

October 31, 2017, 09:41:47 pm

I have a 1992 Granville with air throttle. The other day stepped on throttle and it quit - Pedal goes down but air did not work throttle. Have it in a repair shop and they tracked it down to the part below. It is in the engine compartment. It appears air is getting to the part but does not translate to any throttle movement. does anyone know what the part is and any suggestions on how to fix or a replacement . Thanks

Re: air throttle problem

Reply #1 – October 31, 2017, 09:50:45 pm

Check and make sure the cable is not broken.

It is a Bendix air throttle cylinder. There are kits for overhauling them if it is not a bad cable.

Re: air throttle problem

Reply #2 – October 31, 2017, 09:52:53 pm

Thanks Brett - will look at that tomorrow

Re: air throttle problem

Reply #3 – October 31, 2017, 11:13:03 pm

If the cable is ok then take this cylinder apart and clean it out then apply a thin coat of synthetic grease to the walls of it and parts then rebuild. I had same issue with a 94 Gv and finally fixed it by doing this. I also had it stick in the open position and could not slow revs down to stop.
JohnH

Re: air throttle problem

Reply #4 – October 31, 2017, 11:15:52 pm

Howard,

I have had some experience with the Bendix cruise control and throttle system. I had to restore my throttle cable, because it was deteriorating from the high engine compartment heat. Parts for this system can be VERY hard to find. I was lucky enough to locate rebuild kits for the CC-5 air cylinder, including a brand new potentiometer. These parts I found after a long search on eBay. I have not used the kits yet, because my system is still operating well - I'm saving the parts for a future rebuild when necessary. You should periodically search eBay for "Bendix Cruise Control". You might luck out and find some good stuff!

The link below will lead you to the best collection of information available anywhere on the Web. it was put together by the Blue Bird Wanderlodge owners forum, because their old coaches also use this system. Pay particular attention to the .pdf files. The last .pdf on the list is where you should start looking for info. Note that the system used on our coaches is a modification of the original Bendix cruise control. Foretravel added a couple extra valves to combine the air throttle with the cruise control. You won't see the Foretravel air throttle mentioned in the Bendix literature.

I will add a copy of a "marked up" diagram I made of the cruise control, showing the added components that provide the throttle control.

http://www.wanderlodgegurus.com/database/?m&dir=Chassis/Cruise%20Control/Bendix%20Cruise

For additional info, you can also search for "Bendix Cruise Control" on the Wanderlodge Gurus Forum search page:

Wanderlodge Gurus - The Member Funded Wanderlodge Forum - Search

Re: air throttle problem

Reply #5 – November 01, 2017, 12:03:36 am

John and Chuck - thank you.

Re: air throttle problem

Reply #6 – November 01, 2017, 12:13:27 am

FIndiTParts lists a rebuild kit for the CC-5 air cylinder. There is not much in this kit - just a few O-rings, a plastic "wear" ring, and some assembly lube. If you can find one, it would be nice to have on hand in case you need to replace any of the "soft" parts during a CC-5 cylinder rebuild. I'm betting if you call them you will find it is on back order, but I could be wrong. It would be worth a try!

BX102315 by BENDIX - MAINTENANCE KIT

Re: air throttle problem

Reply #7 – November 01, 2017, 12:28:17 am

The Bendix 101951 potentiometer and spring assembly (the blue thing on the end of the cylinder) is not included in the CC-5 rebuild kit. Below is a small photo of the kit from the order receipt when I ordered mine on eBay (in July, 2016):

Re: air throttle problem

Reply #8 – November 01, 2017, 09:34:04 am

Howard,

In case you find your problem is, like Brett mentioned, in the throttle cable here is a little info from my experience. Best case scenario would be that your cable has simply become "unconnected" at either end, and can be reattached. The worst case would be a broken cable, because my search has never turned up any source for a replacement.

What happened on my coach was the external cable sheath disintegrated from exposure to engine compartment heat. When the throttle cable was pulled by the CC-5 air cylinder, the frayed cable housing was flexing, so that the wire cable was not moving the throttle linkage the correct amount. I caught this problem before the last remaining inner lining came apart, and was able to rebuild the outer housing to "as good as new" condition. This restored the proper operation of my throttle (and cruise control).

Details in link below:

Williams Controls WM453109 Air Throttle Valve

Re: air throttle problem

Reply #9 – November 01, 2017, 09:17:33 pm

Thanks Brett, Chuck and John - I have spoken with the mechanic (I am not there) and it may be a broken cable, although we are working on getting rebuild kit also. Under the worst case scenario what does one do when no part exists or one can't be found. Are there alternatives or replacement equipment - or do you wind up selling your fore travel for parts (sad face)

Re: air throttle problem

Reply #10 – November 01, 2017, 10:40:22 pm

A good tech may suggest alternate solution, as it's a fairly simple function. And then there's salvage vehicles. Does it really need a cable or can the linear actuator be moved with a couple of fabricated brackets?

Re: air throttle problem

Reply #11 – November 01, 2017, 11:14:02 pm

Quote from: hjrein – November 01, 2017, 09:17:33 pm

Under the worst case scenario what does one do when no part exists or one can't be found. Are there alternatives or replacement equipment - or do you wind up selling your fore travel for parts.

If your cruise control is inoperative, there are replacement systems that can take over that function. However, most of the ones I've read about still require the CC-5 air cylinder and throttle cable to operate the engine throttle lever. I did find one reference to a replacement throttle control setup that might be adaptable to your coach. See link below:

Air Throttle

Once you know exactly what parts are "broken" on your coach, then you will have a better idea how to proceed. I would suggest spending some time reading all you can about the cruise control/air throttle, both on this Forum and on the Blue Bird forums. You may come across some solution to your problem.

Here are some threads from our Forum to get you started:

removing bendix cruise control on my U225.

Air throttle on our coach?.

Re: air throttle problem

Reply #12 – November 02, 2017, 10:48:18 am

The cable on my Bendix throttle broke from chafing this summer. I purchased a replacement cable from Foretravel. The cable was a bit shorter than the original but all I had to do was move the the throttle assembly. Was not difficult. I posted the failure and solution on the Forum.

Roland

Re: air throttle problem

Reply #13 – November 02, 2017, 10:53:28 am

Here is the Forum link No throttle or cruise control 1993 u280 40 foot
Hope the link works.

Roland

Re: air throttle problem

Reply #14 – November 02, 2017, 10:58:57 am

Roland,

The link works fine. Curse my oldheimers! I forgot all about you replacing that cable - this will be a big help to Howard, I am sure.

Note To All: Be sure to read through the complete thread linked by Roland above. Contains a CLASSIC photo of "Drive By Rope".

Re: air throttle problem

Reply #15 – November 03, 2017, 12:07:51 am

Again, thanks to all. Good move on the cable Roland. I am sure with the help you all have given we will find a solution. Still waiting to hear from mechanic if cable is broken - sure would feel better if it isn't. Thanks again

Re: air throttle problem

Reply #16 – November 07, 2017, 11:54:58 am

Don't keep us in suspense. Did you get the problem resolved.

Roland

Re: air throttle problem

Reply #17 – November 07, 2017, 10:14:39 pm

The RV is in Texas and I am in Nevada, but the mechanic, (certainly not a foretravel specialist or a Air throttle expert) believes it is just the cc5 cylinder and will be doing a rebuild this week. They say the cable is not broken, hope they are right. So as of right now its not fixed. I can only hope the cc-5 kit is all it needs. Will update and / or have more questions once they do the rebuilt.
The suspense is killing me too (smiley face but I do not know how to do that)

Re: air throttle problem

Reply #18 – November 08, 2017, 12:08:34 am

: - )

: - )

Or emoticon above.

Re: air throttle problem

Reply #19 – November 08, 2017, 12:31:24 am

Howard, maybe all he needs to do is what I suggested at first. Take apart and grease inside of cylinder and parts- rebuild and test.
JohnH

Re: air throttle problem

Reply #20 – November 08, 2017, 11:27:27 pm

John I am thinking (and hoping) you may be right. Hard to believe anything could ever be a simple fix -

and still can't figure out how to get that smiley face emoticon in my post

Thats what I get when I hit the smiley face emoticon

Re: air throttle problem

Reply #21 – November 14, 2017, 11:54:53 pm

Latest update on air throttle problem. Mechanic rebuilt the cc5 cylinder (he swore that was the problem), but it turned out the cable is broken. So now on the look out for a new cable (that probably does not exist) or having one fabricated (if possible).

Re: air throttle problem

Reply #22 – November 15, 2017, 07:54:37 am

Quote from: hjrein – November 14, 2017, 11:54:53 pm

Latest update on air throttle problem. Mechanic rebuilt the cc5 cylinder (he swore that was the problem), but it turned out the cable is broken. So now on the look out for a new cable (that probably does not exist) or having one fabricated (if possible).

Your cable options have been explained (earlier posts). I'd be on the lookout for a new mechanic.

Re: air throttle problem

Reply #23 – November 15, 2017, 10:29:36 am

Quote from: hjrein – November 14, 2017, 11:54:53 pm

Latest update on air throttle problem. Mechanic rebuilt the cc5 cylinder (he swore that was the problem), but it turned out the cable is broken. So now on the look out for a new cable (that probably does not exist) or having one fabricated (if possible).

Your solution is in this thread see replies 13 and 14. And I second the new mechanic suggestion. The reason I say this is that it is not just a matter of replacing the cable but diagnosing and fixing the reason for the failure. Mine was chafing which I resolved.

Roland

Re: air throttle problem

Reply #24 – November 15, 2017, 11:38:39 am

Both you guys are right - I have been using your suggestions and reviewing earlier posts and have no doubt that with the help given I will resolve the issue. Based on several earlier posts I checked the cable and told the mechanic I thought it was the cable, but I was unable to spend anymore time with them other then to pass on my thoughts.

As for the mechanic, I was kind of stuck between a rock and a hard place. Broke down on I45 in Spring TX - I 45 is a major traffic jam all the time so not a great place to be. It was late Friday afternoon and needed to get off the road and to someplace for repairs all in the one tow my tow insurance covers. These guys were the only RV repair facility nearby (at least that I was aware of).

Unfortunately we were on our way home (Nevada) from Texas and had a deadline as to when we had to be back. I was unable to stay in Texas and am unable to get back until after Christmas so I was not able to do any overseeing - but I have been able to share all your good info with the mechanic - who had said they weren't all that familiar with the air throttle system - but they were very positive that they would fix it somehow. I believe with all your help that I have been able to share with them, they will get it done. But I will probably be paying them for some OTJ training. I really should be paying you guys.
Again, thanks everyone for the help. I will let you know how things turn out, where we find parts or have things fabricated so others may have the info.

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