Exhaust brake quit working

[captron33]

Lets try this again! Need some help. Cummins 400 isl, spartan chasis 2006 travel supreme.
I guess next will be taking it to a tech!

[wolfe10]

With a two stage engine compression brake, you WILL have an electric signal that both downshifts the Allison (left or only shift pad window will change from 6 to some lower gear-- often 2nd or 4th) AND will signal the engine ECU to apply either 3 (low) or 6 (high) compression braking.

[captron33]

Its labeled exhaust brake on the switch. Hi and low. Obviously I’m not a mechanic, i will take to one to get it looked at and fixed. Its in storage for 6 months or so for now. Spartan told me the only electrical component is a diode. So no cb,s to check out.

[wolfe10]

captron33 wrote:
No, probably not electric.

Please explain what this means.

Thanks.

[wolfe10]

captron33 wrote:
Spartan confirmed i have a 2 stage exhaust brake., based on my vin number.

No such thing.

If two stage, it is an ENGINE COMPRESSION BRAKE.

[Ray_IN]

captron33 wrote:
Spartan confirmed i have a 2 stage exhaust brake., based on my vin number.

Then your engine has a 2-stage engine compression(Jake) brake, not an exhaust brake. The Jacobs compression brake opens the exhaust valves just before the piston reaches TDC on compression stroke.
reference: https://official.bankspower.com/tech_article/how-an-exhaust-brake-works/

and
https://www.jacobsvehiclesystems.com/technologies/compression-release-engine-brake

[oldave]

2-stage exhaust brake? Are you sure? Not an engine brake? I believe a 2-stage is an engine brake.
An engine brake is much more effective.

[larry_cad]

captron33 wrote:
No, probably not electric.

Then I would look into the butterfly valve mechanical operation. The valve is easy to remove and then it is easy to verify if the valve is working.

[captron33]

No, probably not electric.

[larry_cad]

captron33 wrote:
Spartan confirmed i have a 2 stage exhaust brake., based on my vin number.

Did they offer any suggestions on the problem?

[captron33]

Spartan confirmed i have a 2 stage exhaust brake., based on my vin number.

[Ray_IN]

Blaster Man wrote:
I had an 09 Allegiance with an ISL 400...it had a two stage engine brake...not an exhaust brake.

It would sure help if captron33 also told about his MH and type exhaust brake.

[larry_cad]

Blaster Man wrote:
I had an 09 Allegiance with an ISL 400...it had a two stage engine brake...not an exhaust brake.

Uhhhhh........gee Thanks!

[Blaster_Man]

I had an 09 Allegiance with an ISL 400...it had a two stage engine brake...not an exhaust brake.

[wolfe10]

As you can see, we need more information to be of assistance.

[keefr]

If it's a PAC brake, a likely cause is lack of lubrication on the pivot. It's not difficult to remove the unit, and if it can be freed, great. I had to have the exhaust brake replaced on my motorhome shortly after I got it, and it wasn't hugely expensive. I subsequently replaced it again with an upgraded brake that is designed to be effective at lower engine rpm. Again, not a huge expense.