jaks brake controls

[ttomas]

Can someone tell me what controll wires I need to run to the front of the bus, and or battery wires etc. for the jake brakes?  I am fixing to put the floor back and want to run any and all wires first thanks Tomas

[Don4107]

What ever you do I would run a few extra wires for future toys er make that upgrades.  Are there any abandoned wires from the original harness?

[DrivingMissLazy]

Can someone tell me what controll wires I need to run to the front of the bus, and or battery wires etc. for the jake brakes?  I am fixing to put the floor back and want to run any and all wires first thanks Tomas

A minimum of three for the Jake plus at least three spares. Hot wire should be a switched and fused hot from a rear connection box. One wire forward from the buffer switch to the Hi-Low-Off switch and two wires from this switch back to the Jake solenoids under the valve covers.
Richard

[Nick Badame Refrig/ACC]

Hi TT,

If you have a manual for your bus, then you may be able to find the factory installed wires and terminals for Jakes,

that most busses allready have from the factory. Thats what I did and it cut alot of time off the install.

Then you would only need to tye into the harness at the engine then run a switch to the dash from the front panel.

Good Luck
Nick-

[prevost82]

here a simple schematic
Ron

[TomC]

In a nut shell- you want to run a three wire cable (15amp extension cord works well) from the engine to the drivers compartment.  You start the power source from the engine compartment through a 20 amp (or what's required) fuse, through the buffer switch on the engine then onto the drivers compartment.  If you have a clutch, you have to put a micro switch on the clutch pedal and run the power through there also.  Then the power goes to first an on/off switch, then to a high/low switch OR to a on-on-off double pole switch wired so that low is one head and high is both heads.  Wire to the other two wires in the extension cord to each of the Jake units on the engine.  Good Luck, TomC

[ttomas]

Thanks again, This board makes bus conversions way easier.

[Ncbob]

Not being one to try to start controversy (I have an 8V71 and a 4 speed Spicer in my MC5) I don't glean enough information out of any of these posts which would guide me to have my Jake's installed one way or another. so, let's proceed.....

Since the question of Jake's comes up so often on this and the other Boards, and many of you have years of experience driving heavy trucks, I cannot see that there is any one rule that applies to buses.

Aren't we talking about, in the case of the 35'ers about 30,000 lbs, average?  And in the case of the 40'er
an average of 40,000 lbs?  We're not really talking about a dual purpose train hauling up to 80,000 lbs at highway speeds.

In most cases we're running Detroit's of 6 or 8 cylinder configuration. Yes, some are running 50's or 60's and some are re-powering with Cummins or Cats.  The compression braking in connection with the make
of an engine is as different as night is to day so how can there be a set rule for all of us?

Some of you would like a setup to only pull in 1/2 of the total braking with the selection of a 2 way switch. For me mine are either off or on.  I don't the need of a half way.

Richard offers a suggestion of a 3 wire harness, which is fine that offers options... Tom C has another opinion...but he's running an RTS with a non-Detroit.

What I'm driving at guys is...there isn't one solution to a variable equation for all buses or the terrain you happen to be running. Granted, I'm a newbie, only had my bus for a year and added my Jake's  after my first encounter with the mountains in KY, TN and NC. Made a believer out of me...I needed them!

I leave mine on "all the time" unless I'm in the flatlands of GA or FL and only then. if traffic is flowing smoothly on the Interstate I might switch them 'off'...but only when I feel that 'coasting' is to my benefit when traffic is strung out and I can keep a good interval.  Should I encounter, even the slightest resemblance of 'stop & go' traffic...they come on.

I didn't mean for this to be a 'dissertation on the use of Jake's'..it's just my way of asking if the rule of thumb for the truckers...applies to us.

Your call...and I'm looking forward to your answers.

NCbob

[DrivingMissLazy]

While out on the interstate's I would never consider leaving the Jakes on all the time. Too many small ups and downs and each time you let off the throttle, the Jakes would come on. Also, mountain driving in the west is considerable different than in the east (And I think I have driven most, if not all of them). Even the cruise control would turn them on at times.

As Tom has so eloquently pointed out, a trip down the grapevine makes use of both the hi and low settings of the Jakes many times in that one downgrade, and there are many many more downgrades where the hi and low as well as off are very convenient.
My advice is that if you are going to install Jakes, install the hi-lo function and install the switch so it is very convenient to reach while you are sitting in your normal driving position, without having to stretch.
Richard

[TomC]

A-men Richard!

[DrivingMissLazy]

One important thing I forgot regarding Jake installation.

First, the reason why. I had a Jake solenoid under the valve cover go bad. It shorted partially to ground and the excessive current destroyed the micro-switch in the buffer switch assembly. And that is an expensive little bugger. Fortunately the wiring from the buffer switch to the hi-low-off switch in the front and the wiring back again to the rear was not destroyed before the fuse blew, but I think I was fortunate.

Therefore, I strongly suggest that your wiring include two of the small cube control relays available at any auto supply store. Wire it so that the hi-low-off switch and buffer switch only control the control relays. A separate fuse and wiring controls the actual power to the Jake solenoids thru the control relays. That way, if you ever have a fault in the Jake's you only destroy a cheap control relay. And you still have one side of the Jake's operational till you get home and get it fixed.
Richard