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Guest dew110CSW

Never seen it on a Landie, but I've seen it done on HGVs a few times.

Most of them were next to useless though, and never used unless it was a last ditch attempt and bringing it to a halt.

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odd i'd swear i'd answered this saying i wouldnt bother as they are sodding useless. normally they are a butterfly in the zorst, operated however you like.

on the coaches i drive with them the only effect seems to be a change in the engine note & no accleration if you forget to take your foot off it. doesnt stop much quicker though.

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Some of the Merc Atego's i've driven have had very effective exhaust brakes, fantastic for increasing the effective engine breaking on fast downhill descents, but i'm not convinced they're suitable or applicable to small 4x4 usage. I can see the thought process, but don't think it would be a go-er... prove me wrong though, thats how innovation works!

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sorry to interrupt , i've thought of fitting one on my 90 but could'nt come up with a way of doing it ie. finding one small enough . i also was'nt convinced it would work , but it sounds like it works on your mog .

was it standered fit on mogs or have you added it yourself ??

used in the correct way they are very good at what they do , but you have to remember they were never designed to stop you and should'nt be expected to .

the one on my wagon is perfectly capable of holding my speed just below the speed limiter if i ask it to , even fully loaded down windy hill or brighouse with just the occasional dab on the brakes .

thats what they were designed to do . if your finding it useless than it's either broke or it's being used wrong ,

you need to have the engine revs up because the higher the revs the better it will work , and they should never be used as a main brake . use it as a brake aid and a way of keeping your brakes cool and you will get used to them . i still find myself swinging me leg in my land rover looking for it .

did someone mention coaches , i drove coaches for a while years ago and they had telmars , and they could put you through the windscreen , if , and when they worked . one off them on a land rover would be good as they are not dependent on speed like the exhaust brake , but they are a heavy piece of kit rapped around your propshaft .

i think it was cat engines and maybe a few others used to fit jacobs brakes , or jake brake , that from memory worked on the exhaust valves , i think , but i never drove one so i don't know if they were any good or not .

this would be a good project for an engineer to have a go at , cos it sounds like it works on your mog .

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Guest dew110CSW
did someone mention coaches , i drove coaches for a while years ago and they had telmars , and they could put you through the windscreen , if , and when they worked . one off them on a land rover would be good as they are not dependent on speed like the exhaust brake , but they are a heavy piece of kit rapped around your propshaft .

I presume by these you mean a form of Retarder, where the kit around the propshaft was an electromagnet, I have found those to be effective in Coaches, but due to the weight of the things are impratical for anything else.

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Hi

Yes the exhaust brake is standard on turbo SBU Unimog’s, but then braking wise stopping the SBU’s has never been a problem due to the big disk brakes, Telma brakes cannot be used on Unimog’s due to the torque tubes that enclose the prop shafts.

Designing & Fitting an exhaust brake to a Land Rover isn’t really a problem, the problem is the Land Rover engine, they are simply not robust enough to take all the extra loads, are the turbo chargers designed with high pressure seals on the exhaust side of the turbine to cope with the back pressure that wouldn’t normally be there, would the exhaust manifold and gaskets and its attachment to the head be strong enough for the back pressure that wouldn’t normally be there, on newer modals when cold the EGR system is going to be a problem even when hot will the back pressure force it open, are the valve guides + sealing effectiveness enough to stop pressure leakage etc into the engine via the stem and guide, are the valves, seats and alloy of the head going to be ok as a compressed hot gas is always hotter then an uncompressed hot gas, how will it fair with the electronics of a CRD and ECU’s as light automotive ones won’t be programmed or triggered like on truck ECU’s.

b101uk

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Hi

Yes the exhaust brake is standard on turbo SBU Unimog’s, but then braking wise stopping the SBU’s has never been a problem due to the big disk brakes, Telma brakes cannot be used on Unimog’s due to the torque tubes that enclose the prop shafts.

Designing & Fitting an exhaust brake to a Land Rover isn’t really a problem, the problem is the Land Rover engine, they are simply not robust enough to take all the extra loads, are the turbo chargers designed with high pressure seals on the exhaust side of the turbine to cope with the back pressure that wouldn’t normally be there, would the exhaust manifold and gaskets and its attachment to the head be strong enough for the back pressure that wouldn’t normally be there, on newer modals when cold the EGR system is going to be a problem even when hot will the back pressure force it open, are the valve guides + sealing effectiveness enough to stop pressure leakage etc into the engine via the stem and guide, are the valves, seats and alloy of the head going to be ok as a compressed hot gas is always hotter then an uncompressed hot gas, how will it fair with the electronics of a CRD and ECU’s as light automotive ones won’t be programmed or triggered like on truck ECU’s.

b101uk

ah yes , i remember my fitter mate saying the same thing , " no problem getting one on" , but he was'nt sure the engine could cope with it .

i think thats why it was never investigated further . good point .

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ah yes , i remember my fitter mate saying the same thing , " no problem getting one on" , but he was'nt sure the engine could cope with it .

i think thats why it was never investigated further . good point .

just remembered this aswell ,

while chatting to my fitter mate about this very subject we had a look at a little 7.5t leyland that he had in the garage for service , but i quickly forgot about the exhaust brake and started dreaming about the little cummins it was bolted too.

snapped out of that dream pretty quick though !!

150hp cummins , mmmmmmmm " lurvly"

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Jake brake - wonderful... on a Cummins powered IHI if I remember rightly :) . Out in Kiwi in the mid - 80's. Can't remember a lot of detail (too long ago now :rolleyes: ), just remember it was great for downhill, pulling some speed off before corners etc.

When I had the RR converted to Mazda 3.5 Tdi, it was supposed to come complete with exhaust brake, but for some reason that was never fitted. Probably should have chased that up - it was supposed to be included in the conversion cost... :unsure:

Only other one I've driven with an exhaust brake was a Scania 117m - Class One (as used to be!) delivering for Gateway. Useful item on long downhill motorway sections, and easing off speed for motorway off-ramps.

Cheers,

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isuzu troopers have them, but the seize up often. they're just a flap, attached by cable to the brake pedal at the entry to the downpipe so are in a rather harsh environment all the time.

mine never worked and i was not connected when i put the engine in the landy so i cant comment on its effectiveness. would now like to cut it out to try and free up a bit more exhaust flow. would take a squillion short strokes with a pad saw x2 to cut it out so i've never bothered. i tried unbolting it, but it refused to budge :(

some ay the inclination will hit me and i shall see about fully removing it one way or the other.

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Guest dew110CSW

Sorry to bring this back up, but I've been having a thought on it.

A retarder, aka a magnet round the prop, could make a very effective tool on a Landie if it wasn't for the fact they weigh half a tonne. I thought that if done right, you could use them as a form of Hill Decent Control by knocking it on a couple of notches and it would hold at a speed. Also, they are VERY effective at stopping vehicles.

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A retarder, aka a magnet round the prop, could make a very effective tool on a Landie if it wasn't for the fact they weigh half a tonne. I thought that if done right, you could use them as a form of Hill Decent Control by knocking it on a couple of notches and it would hold at a speed. Also, they are VERY effective at stopping vehicles.

thats how i use them on coaches. leaky gearbox seal dripping oil on them means you create a james bond style smoke screen too :D

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Guest dew110CSW

Yeah, I always remember the school buses were fitted with them, click it down a couple and you'd feel it come on, used to be able to bring the bus to a stop down a VERY steep hill using only the Retarder

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one of our many coaches is so lazy to drive, cruise control lever, retarder lever & autobox - you dont need feet :D

i prefer driving manuals though as ive always slowed on gears & find myself approaching stuff to quick by just lifting off in an auto.

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