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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: rdbishop on August 13, 2007, 08:32:32 PM

Title: Sticking jake brakes
Post by: rdbishop on August 13, 2007, 08:32:32 PM
Little help please,

The wife and I decided to go to Rockport tx. to see her brother. We wanted to take the bus which has sat unused for 2 yrs. Anyway,to make a short story long...I took the bus to town to get it inspected and everything worked fine. On the way back home I came to a red light and let off the gas pedal. ,the jakes came on(I always leave them on) ,worked as they should and we stopped. As I left the red light I had a lot of black smoke and no power. I pulled over and finally,after some time, turned off jake switch and everything went back to O.K. I got home and checked the micro sw. and was o.k.
We went ahead and made our trip to the coast and every once in a while I turned jake on with the same results as before. So, my question is, would the problem be in the governer, and can I fix it. I miss Jake!!
Title: Re: Sticking jake brakes
Post by: Nick Badame Refrig/ACC on August 13, 2007, 08:58:16 PM
Hi RD,

It sounds like the fast idle buffer switch may have to be cleaned or serviced. That micro switch is most likely ok but the shaft that

activates it may be leaking fuel through the seal and collecting dirt.

Good Luck
Nick-
Title: Re: Sticking jake brakes
Post by: TomC on August 13, 2007, 09:12:04 PM
Nothing wrong with the Jakes themselves, just the buffer switch as said before.  Just turn it on only when you need them-generally going down a long hill-not needed signal to signal in town.  Good Luck, TomC
Title: Re: Sticking jake brakes
Post by: rdbishop on August 13, 2007, 09:25:40 PM
Thanks for the replys guys.

I really want to get jake fixed as I use them all the time. Don't you all leave yours on? The mech. said it wouldn't hurt anything.

Thanks again,

Richard
Title: Re: Sticking jake brakes
Post by: TomC on August 13, 2007, 10:31:07 PM
I only use them on long down hills or coming off the freeway.  Using them in town is one of the reasons many towns don't allow Jake Brake use because of the racket they make with businesses and residences close by.  No it doesn't hurt anything-it's more a consideration thing towards others with the noise that Jakes make.  This is how I drive my bus and this is how I drove my truck for 21 years cross country.  Use your brakes in town, and think of the Jake brake as a assistant to the long down hills.  That's why I say to only turn it on when you really need it.  Good Luck, TomC
Title: Re: Sticking jake brakes
Post by: pvcces on August 13, 2007, 11:43:51 PM
dbishop, if you leave the Jakes on, every time that you come off the throttle, you will throw some energy away. Every time that you slow down more than you need to, you will need to burn fuel to regain your speed.

A good example of what I am talking about is when you use the Jakes with a cruise control. While running on nearly level roads, the engine will alternate between Jakes on and slowing to throttle on and accelerating unless you get a dead level road and the throttle stabilizes at a steady speed.

We don't turn ours on unless we need them for just this reason.

Tom Caffrey
Title: Re: Sticking jake brakes
Post by: Barn Owl on August 14, 2007, 06:39:46 AM
On the lightweight 4106 the jakes work so well it can be too much at times. I tried to leave them on at first, but trying to feather the throttle right above jake engagement was too much trouble, and difficult without some sort of indent to find the right spot every time. My accelerator pedal has been converted to an air throttle and I probably don't get the feedback that an original system would. I also don't like having to take my hand off the wheel to hunt for and engage the switch. Last week in addition to the switch at the control panel, I added a "momentary on" switch that I can operate with my foot. I stuck it in the old clutch pedal hole. When I need them only now and then, I just use the foot switch. Simple and easy.

The attached photo shows the switch that I added. The driver's area is still not completely finished, excuse the mess. Left to right you will see the horn switch, high-low beam switch and the jake switch. NAPA has a nice momentary switch that looks like the high low beam one for only $16. I went with the $4 starter switch from a local auto parts dealer to test the concept first.
Title: Re: Sticking jake brakes
Post by: prevost82 on August 14, 2007, 09:28:21 AM
I leave mine on all the time, but I also live in the mountains on the west coast. I have mine setup so if I want to slow down without the Jakes coming on I just leave my foot on the fuel petal, if I want the Jake on I take my foot off the petal. I consider them part of the braking system.
Ron
Title: Re: Sticking jake brakes
Post by: rdbishop on August 14, 2007, 11:10:23 AM
Thanks Ron,

That's the way I normally use mine. With my new muffler they are pretty quite. When I go through a town that says turn them off I do. However they still do not work right. I sprayed the area with brake cleaner, and it all looks new. Still doesn't work. My guess is I need to open the gov. and see what's happening.

Thanks again,

Richard