King Control Throttle System

[jimc99999]

Mine failed once where the cotter pin that holds the drive pulley, the driven pulley, and the throttle position sensor all on the same shaft failed. At the time I replaced the cotter pin with a small soft aluminum wire because that was what I had handy at the time. That soft aluminum wire failed around 1000 miles later and I'd forgotten to buy cotter pins so I repaired it with a spring steel wire from a spring clip. I do have cotter pins set aside for the next repair but so far the steel wire has held up for 7K miles.

I do also have a bracket kit and I should be gathering the other parts necessary to replace the King throttle control with an air throttle but I haven't started that process yet.

[Preston W]

Does anybody know if there's any maintenance You can perform or lubrication on the king.Control throttle system to keep it going a little bit longer.We have a 1998 Monaco.And I know it was replaced early on and  so far working correctly but it terrifies me to be it out on the road and have it go out.

[CRY1942]

Preston:

Steve Boler. owner of the company who repaired King Controls for years, rebuilt mine just prior to closing up shop. Steve advised me there were simply no more parts available.

When my friends King Control died, was the emphasis for coming up with the Air Throttle Bracket Kit to assist in a conversion.

If it does fail, the old Fly by Rope can get you home.

So far I have not heard of anyone doing King repairs.

Best of luck and wishes.

[jimc99999]

4 hours ago, CRY1942 said:

If it does fail, the old Fly by Rope can get you home.

I have unfortunately had to do the fly by rope a couple times. You don't want to be going far because it is tiring. Also the transmission doesn't downshift normally because of the lack of throttle position sensor. But it's way better than getting towed.

[Preston W]

If  I can ask you a really  stupid question. when they say use the fly by rope system if the king throttle fails.Are you saying we should carry a 45 foot piece of string or cable? And wire it to the throttle to get Home?.It sounds like a nightmare scenario., but yes, better than being towed.  sorry to be stupid. So  you would tie to the throttle spring and feed it up where the bed goes down over the engine? Tiring indeed! 

Yes I see now it is actually fly by rope. Lots of scary information on the internet about it. Some use a piece of p v c to run the cable up from where the bed is. Oh boy. 

Driver runs a string/rope/wire/cable from throttle lever on the engine all the way up to driver seat.  Pull on rope to operate throttle.

Documented in several "classic" past threads on Forum.

 

[CRY1942]

Yep it will work.

Borrowed photo.

[Preston W]

This is some wild picture. Guess I gotta go buy some rope. And gloves.

[Preston W]

6 hours ago, CRY1942 said:

Yep it will work.

Borrowed photo.

 

I can see that if my King controller goes out, and I'm using the rope. When I get on the freeway, we are not stopping!  I am interested in purchased your air system however my rig is still being fixed at the body shop and all my engine material is in it. I  don't know if I have mechanical or digital system. its a 1998. I do have an invoice from the original owner and it says Cummins 350 hp ISC engine.  But I think you'll need a serial number.  do you have any of the air units left?   who would install something like that?   I found an old box with a king controller unit in it, number 9339, but seems it was for our detroit diesel Safari and not a Monaco.  don't think it has any usable parts on it.  Also, I'm reading about some grease zerks that are no the throttle and the possibility of oiling the end of the cable to buy  a little more time? 

Appreciate your knowledge and insight on this.

[Preston W]

Sorry, I forgot to ask one of other thing. you say that this air gap system is for mechanical Cummins 8.3  only. what do you do if you have one of the later models that's digital.  mine is a 1998.And I'll know when I get the serial number where we are.

[CRY1942]

Someone with more knowledge than I, may chime in. I was thinking the ISB, ISC, ISL engines were electronic and not mechanical injected engines. I have only experienced the older mechanical C8.3.

I am of the understanding King made two units a 2500 cruise only model and the 2600 cruise and throttle control.

 

[Preston W]

Thanks. A lot . i'm almost afraid to ask.. what happens if you have the electronic model and the king controller goes out?

[jimc99999]

19 hours ago, Preston W said:

Thanks. A lot . i'm almost afraid to ask.. what happens if you have the electronic model and the king controller goes out?

The King controller is an electronically controlled motor to pull a physical cable-actuated throttle. Even if the motor has an ECU, you can pull the throttle and make it rev up. In fact an ECU-controlled motor probably has the throttle position sensor on the throttle, so it might work better than on the mechanical motors.

[Preston W]

Thank you much.I have the engine type and serial number now.But i'm going to call cummins on monday just to see if it's mechanical or electronic to make sure because it's a 1998 coach, about when they were changing out the engines to electronic. so could have been either. Once I get my coach back next week from the accident repair, I'll give that king controller box a visual,  lubricate what I can and just do an inspection. I haven't had any indication that the thing is going bad but murphy's law rules. The only thing I've ever noticed is if I have my hazard blinkers on while going up a real steep hill and go down into second gear The coach will lurch.Every time the blinker goes on , so I just don't do that.

 

[Craggar]

16 hours ago, Preston W said:

Thank you much.I have the engine type and serial number now.But i'm going to call cummins on monday just to see if it's mechanical or electronic to make sure because it's a 1998 coach, about when they were changing out the engines to electronic. so could have been either. Once I get my coach back next week from the accident repair, I'll give that king controller box a visual,  lubricate what I can and just do an inspection. I haven't had any indication that the thing is going bad but murphy's law rules. The only thing I've ever noticed is if I have my hazard blinkers on while going up a real steep hill and go down into second gear The coach will lurch.Every time the blinker goes on , so I just don't do that.

 

If you have the P7100 injection pump I doubt yours is electronic. When I was working on my pump everything I was reading was about mechanical. I also had some shifting issues going up hills but not related to signal lights which could possibly be a bad ground. In my case I reset the TPS and everything has been fine since. Easy to do and worth a try.

[CRY1942]

If your King Control Box has four (4) connectors, it is providing both Throttle and Cruise functions. Not absolutely certain as I have only first hand knowledge of the four connector box, but a drawing I have, shows the King Cruise (ONLY) box just has two (2) connectors.

The attached wiring drawing is corrected, what is marked as Throttle Position Sensor (TPS) is incorrect, this is actually a "filter" found on some installations.

The King Control Box provided TPS information to the Allison. Conversion to an Air Throttle requires the installation of a TPS module.

[Preston W]

Thanks for the schematic on this.  I will  have the rig back later this week and will examine. In the meantime, i called Cummins in Avondale  today, gave him the serial number of model and he looked it up. Our engine was manufactured in 1997 he says and he didn't see any indication that anything was electronic. so I'm betting its mechanical and will confirm the king control.  Just wondering, who in the world can install something like this? Way beyond my pay grade?

Many thanks

[CRY1942]

The Air Throttle Bracket Kit can reasonably be installed by the average DIY fellow.

There are 32 pages of detailed instructions and many photos.  The hardest part is running an airline from the dash to the engine room.

Best wishes.

[Preston W]

Thanks very much, Charles.And what is the current status of the kits you have available? Any left at all? Current pricing? You mentioned that an airline  has to be run back on the coach. I have an airline that goes to the rear of my coach that the hummer h2 braking  system works off of. Wonder if I could just "T" into that line to gain access to an air line? Thank you.

Preston

 

[RoadTripper2084]

Also, I wonder if anyone has had success installing the air pedal system and also a reasonable replacement for the cruise control functionality that the King Control system provides (on some units)?

[CRY1942]

Hello Road Tripper:

Yes, our Air Throttle Bracket Kit has been successfully used by quite a number of folks.

The only known, successful, Cruise Control replace is from Rostra, we have confirmed it's use on a Country Coach and a Foretravel.

Happy to discuss the Air Throttle, contact me at "cry42@windstream.net".

Regards,

[RoadTripper2084]

On 8/8/2024 at 11:59 AM, CRY1942 said:

Hello Road Tripper:

Yes, our Air Throttle Bracket Kit has been successfully used by quite a number of folks.

The only known, successful, Cruise Control replace is from Rostra, we have confirmed it's use on a Country Coach and a Foretravel.

Happy to discuss the Air Throttle, contact me at "cry42@windstream.net".

Regards,

Thank Charles. I'm still holding my air throttle kit in reserve as a contingency should my King Control unit ever fail in an unrepairable fashion. I tend to use my cruise-control a lot so would certainly want to replace that functionality should I ever swap out the King Control.