Skip to main content ↑ ↓
Topic: Jake Brake (Read 1464 times) previous topic - next topic

Re: Jake Brake

Reply #25 –
Thanks for the schematic, Lon. Same one I have. It just has to be a simple wire switch. No, I see you sent me more than the 5346. Time to look a bit closer. Thanks.

Rick, I drove it a couple of hundred miles yesterday (Eugene to 101 and north on 101). Got a chance to use it quite a bit. My first impression is it is A LOT BETTER. The easy downshift to 5th with a manual downshift to 4th eliminates the violent auto downshift. Also, the Jake in 5th is just right for those easy grades in which you just want to avoid speeding up. So far, so good. I think adding the 2 speed will make it just right but the 5th pre-select is a big improvement and I suspect the 2 speed will be too. Post your results too for our little constellation of Jake users.
jor
93 225
95 300
97 270
99 320

Re: Jake Brake

Reply #26 –
Jor,

101 is a good highway to evaluate Jake switch positions especially from Redding to just short of Eugene. I  usually just leave it on for all cylinders as it's perfect for those long interstate grades where the speed will build slowly without it. Have also tried just the 3 cylinder position for the downhills where there is not enough wind resistance to keep the speed.

The Jake noise on the Detroit is not much above the normal exhaust so it can be left on in residential areas without causing any problems. Some big rigs Jakes are enough to wake the dead.

Pierce

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Jake Brake

Reply #27 –
I'm pretty sure mine is wired the same. I figured the only way to wire low and high was with a 2 speed switch and a diode.
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: Jake Brake

Reply #28 –
Jor,
Thanks for the results. Will post my experience when I get it done.
Rick
Rick

Re: Jake Brake

Reply #29 –
Quote
I'm pretty sure mine is wired the same. I figured the only way to wire low and high was with a 2 speed switch and a diode.
Yea, it shouldn't be difficult but I gave the Eugene Cummins dealer my schematic and I have to say, they seemed a bit unsure of how to proceed. I may end up taking it elsewhere. I was thinking any truck repair shop could do it as all should be familiar with Jakes.

So, how exactly would you rewire it?
jor
93 225
95 300
97 270
99 320

Re: Jake Brake

Reply #31 –
I have a 1995 U300 40' Build # 4627 3176 Cat HD4060 Transmission
Some time back I was on a mission to find out why I only had one stage Jake Switch (on/off) but had a second stage that kicked in when the brake switch was open, I know this because when I would brake along a wall / embankment I could hear the flutter from the exhaust increase.
What I found out was very surprising.
To get to the second stage one of two things had to happen
1 Touch your brakes.    OR
2 Turn off the cruise control Switch.
Yes turn it OFF and I'm not saying tap the brake and disengage.
 Turn the switch OFF the second stag was amazing. I drove my coach for years not knowing this.
Happy trails and I hope this helps some of You Out There..
Andrew
Andrew Buras
Full Timing Since July 2007
1995 U-300 Lived in it for 14 years and now back in it.
Build #4627
Towing 2015 Ford Flex
Still on the road

Re: Jake Brake

Reply #32 –
Quote
but had a second stage that kicked in when the brake switch was open
That's interesting, Andrew. It appears that there are a lot of different Jake configurations out there. Before we changed to the two speed, ours was a one speed and the brake had no effect on it. Not sure about cruise. I did another thread on this but we ended up changing the pre-select gear from 4th to 5th and changing the one speed to a two speed. Like it a lot better now.
jor
93 225
95 300
97 270
99 320
 

Re: Jake Brake

Reply #33 –
Usually, the first position on a Jake is for half of the cylinders (right side on a Detroit) with the second position for all cylinders.

Here is a good site with the theory and operation along with troubleshooting info. It uses a Detroit as an example but is applicable to a CAT also: Jake Brakes

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)