Merc Denning Emergency Brake

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Carpenter
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Merc Denning Emergency Brake

Post by Carpenter »

Hi,
I have a Merc Denning _ next to the air brake lever there is a Red flip up plastic cover with the word "NOT AUS" on it. I assumed it mean Not Australia abbreviated to Not Aus but apparently translated from German to English it means EMERGENCY STOP. I queried this with a Brake specialist prior to knowing the translation and they said nothing to do with the Air Brake system. Anyone got any clues of its use and relevance.
Cheers
Carpenter
kelvin12
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Re: Merc Denning Emergency Brake

Post by kelvin12 »

Emergency engine shut down, maybe....... Not familiar with Merc stuff though.

By the way were you by chance parked up at Coffs Harbour show ground recently. Though it might have been you when I saw the toad / boat trailer. Bus looked great if it was you.

Dirk
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makeminea2stroke
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Re: Merc Denning Emergency Brake

Post by makeminea2stroke »

Hi Carpenter

Sounds like you got your bus done, hope your happy with it.

I sent a few emails a while ago but not sure if you got them or not

Anyway if your still looking for Alloys these may suit
http://www.ebay.com.au/itm/10-X-Alcoa-A ... 337d9c637f

Cheerz
Glen
Carpenter
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Re: Merc Denning Emergency Brake

Post by Carpenter »

Hi Dirk,
Thanks for the tip on maybe engine shutdown.
Was not me at Coffs you saw it is still not finished but very close around end of January hopefully.
How is your project going??
Cheers
Carpenter
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Mr Scania
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Re: Merc Denning Emergency Brake

Post by Mr Scania »

That switch is for the Emergency Brake Release.
It is electrical and should work when it is activated when the Park Brake is released.
It may not work from lack of use.
It also wont work if your park brake tank will not hold air overnight. This tank does not have a gauge.
If you release the brakes with no air in your service brakes you will have to apply the park brake to stop the vehicle.
Carpenter
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Re: Merc Denning Emergency Brake

Post by Carpenter »

Mr Scania wrote:That switch is for the Emergency Brake Release.
It is electrical and should work when it is activated when the Park Brake is released.
It may not work from lack of use.
It also wont work if your park brake tank will not hold air overnight. This tank does not have a gauge.
If you release the brakes with no air in your service brakes you will have to apply the park brake to stop the vehicle.
Thanks Mr Scania,
I figured someone would have to know. :D
Cheers
Carpenter
kelvin12
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Re: Merc Denning Emergency Brake

Post by kelvin12 »

Good you got the right info from Mr Scannia. Thought it was a moral to be you at Coffs, It was identical to the set up you talked about, trailer with hydraulic boat lift. Was going to call in and have a yarn but always on a mission.

Send some photos of the interior when you can.

Dirk
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Bus-1809
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Re: Merc Denning Emergency Brake

Post by Bus-1809 »

It might be to disable any short stop brakes or door interlocks that your coach may have
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Carpenter
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Re: Merc Denning Emergency Brake

Post by Carpenter »

Ok thanks on the Emergency Brake Button. :D

Here is another Question I have.

Just to the left of the drivers seat is a plastic cylinder that looks similar to a Brake fluid size and shape. It has fluid in it and I am told it has 2 wires coming from it. 1 connected , 1 not.
Anyone know what it is, what it does or did?? :?
Cheers
Carpenter
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boronia
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Re: Merc Denning Emergency Brake

Post by boronia »

Hydraulic clutch reservoir ? - there should be a cylinder on the end of the pedal.

Not sure about the wires - maybe some sort of low fluid warning. I think these had an interlock with the exhaust brake and clutch, but can't see it being part of the reservoir.
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Carpenter
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Re: Merc Denning Emergency Brake

Post by Carpenter »

Thanks Boronia,
Makes some sense to me.
So you are saying the clutch is Air over Hydraulic?

There is a button on the floor between the reservoir area and the clutch like the headlight dip switch on old cars which I am told activates the exhaust brake.
With the engine idling if you depress the switch with your foot the Revs drop but when driving there does not appear to be much if any retardation apparent. Any info or experiences much appreciated.
Cheers
Carpenter
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boronia
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Re: Merc Denning Emergency Brake

Post by boronia »

Long time since I've driven one of these, and many of them were wired up differently.

The exhaust brakes weren't very efficient, so when driving normally you may not FEEL much retardation, but you should be able to hear it cut in. They worked best at higher revs - say going down a steep hill drop it back a couple of gears and it will hold the speed. Possibly a switch on the dash that lets you work it off the brake pedal.

On some, when you pushed the clutch pedal, the exhaust brake would cut out to avoid stalling the engine.

Others may have better memories.
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User7526
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Re: Merc Denning Emergency Brake

Post by User7526 »

The 0303s had a switch that allowed the exhaust brake to work with the initial movement of the brake pedal (just the freeplay travel) or you could switch it to manual use and use the floor switch if memory serves me right, it's been a while but I've driven a couple of ex A.P. coaches from that era but I'm fairly confident that that's how they worked. If the switch is set to brake pedal control then the exhaust brake will activate when you are sitting still with the pedal pressed which is why the engine slows a bit. In any case, go for a drive and try the different switch spots etc and get a feel/understanding of it all.

The clutch is definitely air over hydraulic as well, most certainly.

Peta.
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boronia
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Re: Merc Denning Emergency Brake

Post by boronia »

I recall on one of our Scanias, some moron wired the dash switch up to the floor button instead of the pedal, so unless you were savvy to it, you couldn't get the exhaust brake to work at all. First time I got it was a trip to Bathurst and getting down Mt Vic Pass without it was a real challenge :evil:

After driving the O303s for a while and getting used to the EB button on the floor, I'd occasionally revert back to a PD4107, and guess what the button on the floor in exactly the same spot did? :shock: It didn't slow the bus down, but it certainly got people out of the way in a hurry :shock:
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Carpenter
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Re: Merc Denning Emergency Brake

Post by Carpenter »

Peta mechanic wrote:The 0303s had a switch that allowed the exhaust brake to work with the initial movement of the brake pedal (just the freeplay travel) or you could switch it to manual use and use the floor switch if memory serves me right, it's been a while but I've driven a couple of ex A.P. coaches from that era but I'm fairly confident that that's how they worked. If the switch is set to brake pedal control then the exhaust brake will activate when you are sitting still with the pedal pressed which is why the engine slows a bit. In any case, go for a drive and try the different switch spots etc and get a feel/understanding of it all.

The clutch is definitely air over hydraulic as well, most certainly.

Peta.
Peta,
With the floor switch- Does this mean that when pushed once =on: then push again =off- What I am trying to understand is you don't have to keep your foot on the switch for the Exhaust Brake to work?? It is either on or off by pressing :?
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Carpenter
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boronia
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Re: Merc Denning Emergency Brake

Post by boronia »

In all the buses I have driven, The exhaust brake only worked when you had the button pressed.
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User7526
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Re: Merc Denning Emergency Brake

Post by User7526 »

As Boronia said right above me!

Peta.
Carpenter
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Re: Merc Denning Emergency Brake

Post by Carpenter »

Thank You to Both of you. :D
Cheers
Carpenter
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boronia
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Re: Merc Denning Emergency Brake

Post by boronia »

Bus-1809 wrote:It might be to disable any short stop brakes or door interlocks that your coach may have
It would be most unlikely for a coach to have either of these functions fitted, esp one of that age.
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