Engine brake problem

First off you need to know what it is. The early N14's still had a fuel pump on them.

 

Could be a bad connection.The clutch pedal has a "micro-switch" at the top of the foot pedal that could be bad,another micro switch at the fuel pump where accelerator linkage fastens(mechanical engine only).Could be a bad fuse,broken wire.Could just be messed up from sitting.Lots of things to check.
I`m curious,did someone give this truck to you or did you buy it?Sitting is the worst thing for any vehicle.After you get it running smoothly be prepared to replace alot of seals and gaskets.
Most older Cummins should operate at 180 degrees F.Try blocking off the outside radiator with cardboard and fast Idle engine to see if it will come up to 180,colder it is outside the harder this will be to do.Next to impossible to do if the engine fan is engaged.Sounds like you may have a learning project on your hands.Good Luck.

 

Telling him to idle up a cold cummins isn't the best thing to do without an explanation of what he needs to do and watch for.

 

thermostat is probably stuck open and bad wire connection or silenoid on that jake assembly.

 

You sure it's not a Big Cam? Is it the original motor with the truck?

Replace the thermostat with a 190* It's just good sense after having it sit for a few years.

If it is only #2 Jake not working, it is not a clutch or accelerator micro-switch. None of the Jake's would work if that was the case. It's either a wiring problem at the dashboard switch, a broken wire going to #2 Jake, a broken wire inside the valve cover going to the solenoid, or a defective solenoid.

Which it will be engaged if you block off the radiator. No, a much better test is to remove the thermostat (if it's even there) and bring it in and put it in a pan of boiling water and see if it opens and closes correctly. Ideal operating temp for a Cummins is around the 195* mark. 180* is typical, but anything consistently lower isn't healthy.

See above. Jakes are either typically wired to have power go to the on/off switch, then the clutch/accelerator cut switches and then to the dashboard selector switch you you can choose your cylinders.

A lot of people for some reason think that removing a thermostat helps an engine run cooler in the summer months. I've seen a ton of tractors over the years with them stupidly jerked out.

One of the purposes of a thermostat is to hold the water in the radiator long enough to let the fan/airflow cool it, and then it repeats the cycle.

 

he wasnt saying it was the #2 setting on the jake thats not working...he means problem #2.

 

All that explainin' just because I didn't figure that little nugget out.

Well, check the power to the on/off switch with a test light.

Typically, it is a clutch or fuel pump switch. Wiring could be fine, either switch could be out of adjustment. Typically, those switches need to be depressed to complete the circuit.

Good luck.