24 volt jake brakes

[Lee Bradley]

Just had jakes installed on my v8-92. I bought them as 24 volt but the mechanic said something about running them on 12 volts.  My meter is showing 18 ohms per side. Are these 12 or 24 volt?

[thomasinnv]

The 24 volt solenoids will run just fine on 12 volts.

[luvrbus]

Some people use small capacitors on each slave when using 24v solenoids on a 12v, makes it engage faster,but you are fine with either 12V or 24V just be sure you have no more than 0.4 voltage drop because the wires if using a 24V Jake harness are a smaller gauge than the 12V harness   

[Lin]

It's good to know the a 24v Jake will run on 12v.  However, I think that it would be risky to try to do it the other way-- run a 12v Jake on 24v.  For peace of mind, I would want to make sure that the set is really a 24v set and find what voltage is connected to it.  My MC5a is a 24v system, and my Jakes are 12v.  Therefore my 24v switch activates the Jakes through a relay putting out 12v.

[luvrbus]

They work Lin just not great the 24V take 17V to pull in and the 12V take 8V to pull in.I don't understand his ohms reading the 24V are 31 to 38 ohms hot and the 12V are 9.5 to 10.75 hot if he is measuring both solenoids on each bank and coming up with 18 ohms I would say they are running on 12V

[Lee Bradley]

I think they are 24 volt as the seller listed them.  As you add solenoids the ohms are halved; so two 31 to 38 solenoids in parallel would read 15.5 to 19 ohms.

[luvrbus]

  I always get that backwards Lee ,since I test 1 at a time 

[scanzel]

Lee where did you buy them and who installed them. I missed buying a brand new set on Ebay a few weeks ago. I see some guy in Texas selling complete sets off of military 8V92's. Is there a difference with mechanical verses DDEC jakes or is it just that the DDEC is controlling them verses a switch.

[luvrbus]

Lee where did you buy them and who installed them. I missed buying a brand new set on Ebay a few weeks ago. I see some guy in Texas selling complete sets off of military 8V92's. Is there a difference with mechanical verses DDEC jakes or is it just that the DDEC is controlling them verses a switch.

They are the same you just add the buffer switch and a different harness,military will definitely be 24V   

[Lee Bradley]

Lee where did you buy them and who installed them. I missed buying a brand new set on Ebay a few weeks ago. I see some guy in Texas selling complete sets off of military 8V92's. Is there a difference with mechanical verses DDEC jakes or is it just that the DDEC is controlling them verses a switch.

I bought them from the seller in Texas. Pacific Truck Centers in Coburg, OR installed them while the engine was out for a new/reman 748.  Since I am just using them for big hills, I run them off a relay controlled by a switch.

[Lee Bradley]

Lee where did you buy them and who installed them. I missed buying a brand new set on Ebay a few weeks ago. I see some guy in Texas selling complete sets off of military 8V92's. Is there a difference with mechanical verses DDEC jakes or is it just that the DDEC is controlling them verses a switch.

The seller has another set listed.  You have to use the fuel lines for the DDEC engine with jakes.

[luvrbus]

The seller has another set listed.  You have to use the fuel lines for the DDEC engine with jakes.

? what are DDEC fuel lines, they come in flare or o-rings for all DD engines

[Lee Bradley]

Just what the mechanic told me. That the fuel lines that with the mechanical engine jakes would not work with my electronic injectors and the fuel lines on my engine would not work with the jakes.  Sorry I don't know more.

[scanzel]

Lee, is this the person that advertises on Ebay and also sells the tall valve covers. If yes were you pleased with what he sent you. I have a standard so no DDEC to deal with.

[Geoff]

I just tested some 24v Jakes at 12v and 24v and they barely engage at 12v while at 24v they make a resounding CLICK.

--Geoff