Thread: Anti stall, does it exist on a td5?

Originally Posted by Blknight.aus

when they can do that with an aframe on bitumen and no tyre slip I'll be impressed...

Isn't that what auto's are for?

yes but thats the skirts way of doing it.... (and it only works till the auto boils up.)

Originally Posted by JohnR

No it doesn't. You can not stop it without either keying off or putting your foot on the clutch.
p.s. I should have added it has to be in Low range 1st gear.

Sorry but that defies all mechanical logic.

You can only fuel up so much...
You can not produce full torque at idle...
Unless the clutch releases electro/mechanically then the driveline is "locked" from flywheel to tyre(s)...
Stalling it out therefore is inevitable...
ONLY If the torque > braking ability and tyre slip is present it may keep going...

Originally Posted by Tombie

Sorry but that defies all mechanical logic.

You can only fuel up so much...
You can not produce full torque at idle...
Unless the clutch releases electro/mechanically then the driveline is "locked" from flywheel to tyre(s)...
Stalling it out therefore is inevitable...
ONLY If the torque > braking ability and tyre slip is present it may keep going...

It does not stay at idle is lifts the revs to prevent stalling
I am assuming that 99% of the time the tyres will have some slipage and therefore not going to snap the driveline. I would hate to try this with lockers and central diff lock and big sticky tyres! I think something would go !
I am not sure if the ABS come into play as well??? As I am guessing it would not let you lock up all four wheels when it thinks it should be going forward.
It is more than a governor. How much more I am not sure.....

In Low 1st the engine just out drives the brakes, You can sit there with the hand brake on and both feet hard on the brakes, it just keeps going. However I wouldn't recommend this as I'd hate to think of the strain you are putting on the drive train. For sure, if you mechanically locked the wheels something would give, but I'd be putting my money on a diff or axle failing before the engine stalls.

The anti-stall, (electronic hand throttle - torque activated govenor or what ever you want to call it), is very "proactive" and coupled with the TC makes driving up very steep, uneven ground a doddle).

Cheers,

Tim

The way that it actually works in the vids is thusly.....

1. The high idle jack in 1/low activates. This raises the engine RPM where the VNT turbo charger gets enough flow that it can do its job to keep the boost pressure up by actuating its variable vanes. Without the high Idle jack the puma donk doesnt make enough flow to keep its initial boost pressure on and regardless of fuelling the engine will stall out, (which is why the puma is easily stallable in gears other than 1/low)

2. when the engine RPMS drop off from the high idle setting (it has a threshold lets say 10rpm just to pick a number) the govenor function in the ECU bumps up the fueling to the engine. The same as any other diesel engine on the planet right the way back to the peanut oil burner that started it all.

3. as the "govenor" is fueling up the engine its talking to the "driveline control module" and telling it to tell the TC/ABS unit to wake up to itself and go into "diagonal mode"

(normally your traction control/ABS will do whatever the hell it wants to maintain drive/grip activating up to 3 brakes (any of FR,FL,RR,RL) to maintain grip, in "diagonal mode" its limited to one brake per axle so that the other wheel will be able to turn)

4. IF while in "diagonal mode" the RPMs dont increase then the ABS/TC starts to alternate its braking aplications untill it works out what wheels it needs to lock to get the others turning.

5. once motion is attanied the ABS/TC backs off and reaplies as requried and when the engine RPMs return to the nomnal high idle setting ABS/TC turns off untill its needed again.


The proof of how it happens is in all the videos of the puma pulling the trucks.

1 in sand (which is the hardest one to spot it in but once you know what you're looking for you can and I cant find that vid)
2. on the gravel (@1:35 on the vid in a prior post)
3. on the ramps (cant find this vid but you can see the TC stopping then spinning the cocked wheels as the rover "bounces" the tow rope.

The reason its a govenor thing and not antistall is simple.

The system relies on being able to turn wheels If you cant turn any wheels it will stall. If you didnt have the high idle (and remember idle speed is one of the functions of a govenor) to work up the turbo then it wouldnt work either.

Appropriately geared, fueled and given a high enough idle speed to give the govenor the ability to do its job you would never stall any diesel engine. But take away any of those things and unless you have a means of uncoupling the drive you will stall..

unless you have an F1 racing car, (maybe some others) an automatic (which no puma has as standard) what you have is just a govenor with a high idle feature. If its only a govenor it can be stalled.

Originally Posted by Blknight.aus

The reason its a govenor thing and not antistall is simple.
...
If its only a govenor it can be stalled.

Clearly its not "only a govenor" as it can't be stalled, making it an antistall - simple

I think the Puma owners' have tried to suggest this.

So Dave,
"If you didnt have the high idle...it would be a governor" Which we do. The ECU controls this so therefore it is antistall???

" If its only a govenor it can be stalled" Which it can't be, so therefore it is antistall???

Why do you choose not to believe that Puma's have antistall?
A direct quote from the LR site: " The engine is designed to meet modern emissions legislation and features an Anti-Stall device, which intelligently adjusts the fuel required when the engine is working at low speed."

The same brochure for the TD5 does not mention antistall. I know you are going to say it's just marketing guff but I ask my original question:
In a TD5 or earlier (instandard set up) in 1st gear low range, if you put both feet on the brake will it stall??

A Puma will not stall. Therefore it has anitstall.

Cheers,

Originally Posted by Blknight.aus

The way that it actually works in the vids is thusly.....

1. The high idle jack in 1/low activates. This raises the engine RPM where the VNT turbo charger gets enough flow that it can do its job to keep the boost pressure up by actuating its variable vanes. Without the high Idle jack the puma donk doesnt make enough flow to keep its initial boost pressure on and regardless of fuelling the engine will stall out, (which is why the puma is easily stallable in gears other than 1/low)

2. when the engine RPMS drop off from the high idle setting (it has a threshold lets say 10rpm just to pick a number) the govenor function in the ECU bumps up the fueling to the engine. The same as any other diesel engine on the planet right the way back to the peanut oil burner that started it all.

3. as the "govenor" is fueling up the engine its talking to the "driveline control module" and telling it to tell the TC/ABS unit to wake up to itself and go into "diagonal mode"

(normally your traction control/ABS will do whatever the hell it wants to maintain drive/grip activating up to 3 brakes (any of FR,FL,RR,RL) to maintain grip, in "diagonal mode" its limited to one brake per axle so that the other wheel will be able to turn)

4. IF while in "diagonal mode" the RPMs dont increase then the ABS/TC starts to alternate its braking aplications untill it works out what wheels it needs to lock to get the others turning.

5. once motion is attanied the ABS/TC backs off and reaplies as requried and when the engine RPMs return to the nomnal high idle setting ABS/TC turns off untill its needed again.


The proof of how it happens is in all the videos of the puma pulling the trucks.

1 in sand (which is the hardest one to spot it in but once you know what you're looking for you can and I cant find that vid)
2. on the gravel (@1:35 on the vid in a prior post)
3. on the ramps (cant find this vid but you can see the TC stopping then spinning the cocked wheels as the rover "bounces" the tow rope.

The reason its a govenor thing and not antistall is simple.

The system relies on being able to turn wheels If you cant turn any wheels it will stall. If you didnt have the high idle (and remember idle speed is one of the functions of a govenor) to work up the turbo then it wouldnt work either.

Appropriately geared, fueled and given a high enough idle speed to give the govenor the ability to do its job you would never stall any diesel engine. But take away any of those things and unless you have a means of uncoupling the drive you will stall..

unless you have an F1 racing car, (maybe some others) an automatic (which no puma has as standard) what you have is just a govenor with a high idle feature. If its only a govenor it can be stalled.