Community Forums

aragu36 · 05-13-2013, 07:06 PM

When I flip the switch there is a loud screaming noise coming from mid to rear of coach. brake sometimes slightly comes on but it used to retard every stroke now only once or twice. flip the switch and air bleeds and back to no exhaust brake ?I lubed the plunger

Also what cycles the plunger air or fluid?
Switch on brake says
Jacobs exhaust brake

Skip426 · 05-13-2013, 07:46 PM

Jacobs make both engine and exhaust brakes, because it is labled exhaust brake we'll have to assume thats what it is . Exhaust brakes are air pressure activated and fom the sounds of things you have a hose leak between the solinoid and the actuator . The actuator is in the exhaust pipe and the hose runs back to the solinoid usually less than 3' long.
Could be steel braided line be careful , there could be broken ; sharp ; braid wire.

aragu36 · 05-14-2013, 08:59 AM

Ok thanks I see the line. is there a simple way to check
also where can I buy a 3' line ?

Skip426 · 05-14-2013, 09:53 AM

Quote:

Originally Posted by aragu36

Ok thanks I see the line. is there a simple way to check
also where can I buy a 3' line ?

Easiest way may be to remove the line , You could try powering up the solinoid with the engine off and the air system at full pressure , BUT ! there are all sorts of safety concerns; blowing dirt, suspension dropping, so not the best thing to try. Once out any defect should be obvious. Napa, AutoZone, any shop that fabricates hydraulic hoses will be able to make one up, with the original as a sample. You'll just need to tell them 130psi , air pressure in a hot location.

Skip426 · 05-14-2013, 01:09 PM

Because I've seen other posts , of this air line being blown, I just posted about the line its self. There is of course another possible leak ; the air actuator. Possible that the seals have blown out on the air ram, and that's where your leak is . Safest way to check is to remove both the line and the actuator and bench test with compressed air , starting at 20psi, work up in 10psi increments; till leak is found. Seal kits or a rebuilt actuator would probably have to be ordered from the exhaust brake manufacturer.

Bigd9 · 05-14-2013, 01:42 PM

Skip426 has hit the nail right on the head and has given you great advise. Also heed his safety warnings. Compressed air leaking out of a small hole ( "loud screaming noise coming from mid to rear of coach") can injure you. Also I would dump all air from the tanks before working on this. Loosening a fitting while under 120 psi pressure can result in a very interesting moment for you.

Find the exhaust valve on/in the exhaust pipe and you should see a air valve with a plunger that operates the flap inside the exhaust pipe. Follow the air line back to the solenoid valve. Its a good bet that is the line that needs replacing. Could also be either the solenoid or even the air valve, as Skip says, but the line, or a loose fitting, is probably number one on my list (and its cheaper to fix than the other two!).

Good luck and let us know what you find.

aragu36 · 05-14-2013, 02:19 PM

Great info
I removed line to actuator looks ok still trying to find a war to test I might just replace it also I will take actuator out an inspect
Will let you know the outcome
Thanks Again

aragu36 · 05-14-2013, 10:06 PM

Checked hose at 120 psi no leak

Will try to inspect plunger next
Any one know if you can rebuild them and where to find parts

aragu36 · 05-14-2013, 10:09 PM

Quote:

Originally Posted by aragu36

Checked hose at 120 psi no leak

Will try to inspect plunger next
Any one know if you can rebuild them and where to find parts

I tried to call Jacobs
Got a machine ?

Bigd9 · 05-15-2013, 05:47 AM

Might try NAPA Auto Parts. They cater to large vehicles.

aragu36 · 06-06-2013, 01:48 PM

Benched tested plundger found no problem
the gasket was completly gone on one end looked like a horse shoe
Does anyone know where to buy jacobs gaskets #3099094
Thanks