Thread: Exhaust brake details and pictures

Look forward to your exhaust brake build, has been on my to do list for a while. I haven't looked into it but was thinking a simple heel operated switch would be the go. And I will probably look at an air operated system as I already have a good air supply.

Will follow with interest. Keen to hear your thoughts when finished, I want one not for towing but for better engine braking on the long steep down hills in the high country.
Cheers, Andrew.

Got one on a couple of trucks, they are nowhere as good as a jake brake, so you might be disappointed . Normally have a switch on dash and if on will operate the brake when the foot is taken off the go pedal. On a jake brake on one of our trucks you can select the rate of braking by switching from 2 to 4 to 6 cylinders so if you are empty or loaded you can adjust your retardation. The exhaust brake that is just a flap valve on the exhaust is almost useless in my upinion, but might be different on a lighter vehicle . On trucks the flap is operated by air after an E/P energises that directs air to a small piston.
Lindsay.

Thats interesting that jake brakes can be adjustable, i wouldn't have thought it was possible, but there you go.

I dont know what to expect with an exhaust brake on a defender as I havent seen much details for an E/B on this size vehicle, the closest thing is the american pickup truck clips on youtube but you cant really tell how much they slow you down.

I've heard that a lot of after market exhaust brakes on trucks are pretty useless and how much it will slow you down really depends on the characteristics of the engine as well.

In my experience they work extremely well. We have an isuzu cat1 firetruck (approx 13000T) with one fitted and couldnt live with out it around here. In second gear it will slow the truck right down on the steep stuff.

No doubt a jake brake would be better and on bigger trucks the E/B might not work so well but I think it will be good in a defender, especially with an lt95 to hold 3 gear better.

Cheers

Originally Posted by oldyella 76

Got one on a couple of trucks, they are nowhere as good as a jake brake, so you might be disappointed . Normally have a switch on dash and if on will operate the brake when the foot is taken off the go pedal. On a jake brake on one of our trucks you can select the rate of braking by switching from 2 to 4 to 6 cylinders so if you are empty or loaded you can adjust your retardation. The exhaust brake that is just a flap valve on the exhaust is almost useless in my upinion, but might be different on a lighter vehicle . On trucks the flap is operated by air after an E/P energises that directs air to a small piston.
Lindsay.

I hear what your saying about Jake brakes being better, but as you said on a much lighter vehicle an exhaust brake might be effective. I've driven light trucks with exhaust brakes and they definitely do slow you down, so on a lighter Landy it should be a good improvement. I still think it's a worthwhile addition, so see what happens!

Hi there, Ive had a bit of experience with exhaust brakes on several vehicles and the benefit has varied between mild to very usefull however they will never match a Jake brake system. The exhaust brake system basically operates an electric solenoid or a vacuum ram or air pressure ram to blank your exhaust system off and turn your engine into an air compressor and effectively build up pressure in the exhaust system. This is the basic system and it definately has some benefit but it is limited.
If you add a destroking ram to the basic system above you then get considerably more benefit and it is this system that I fitted to my Unimog motorhome and I would find it to be a huge benefit when descending down long hills and rarely even touch the brakes by simply letting the engine do all the work.
For those that are unfamiliar with a destroking ram it is a ram that pulls back on the fuel rack and shuts off all fuel to the engine effectively stalling it creating a situation where your brakes are not fighting the engine which would otherwise be fuelled and desperately trying to Idle.
Its a reasonably simple thing to achieve but makes a large difference

Cheers

So does the destrocking ram close the fuel shut off valve or closes it off else where?

Would love more details on the ram!

Cheers

Hi
In my system on the Unimog the fuel is shut off on the throttle lever on the injector pump and it is the same system which is used to shut down the engine as the mercedes OM366 does not have an electric fuel solenoid like most modern engines. The air ram is attached directly to the throttle lever and when activated it simply pulls the lever back from the idle setting.
I cant think of any reason why you couldnt utilise the fuel solenoid via a relay so that when the ex/brake system is activated the fuel system is shut down without shutting down the ignition etc.

Cheers Bob K

Originally Posted by Jimmy93

I've read a few threads on here about exhaust brakes on different engines and the pros and cons but its a bit hard to find details and pictures of it actually being done.

I am currently going through the process of putting one in from an npr truck into my Defender with Isuzu 4bd1t, its mounted in the exhaust but i am currently working out the wiring and vacuum side of things.

The original plan was to set it up with micro switches on different pedals and the gear stick, however I am leaning more to a simple foot operated vacuum switch at the moment to remove so much unnecessary complications.

Ill post up pictures with my progress and where I source the valves and other bits and pieces from.

Any other pictures, information or suggestions would be great!

I have put them on a couple of my Landies.
One a 2B with the 4BD1 and LT95.
The other my Camper with Chev V8 and NPR gearbox.
I have a dash switch when on, connects the EB solenoid to the brake light wire. I just have to dab the pedal and the EB works. As said, good for long down hill stretches.

Keith