[Comber]

Hi. I have a Civilian parked up that I am building out. Today I wanted to move it and an extremely loud 'alarm' sounds when I turn the ignition to wait for the glow plugs. The glow plug light goes out as normal but the alarm|high pitched single note noise doesnt stop and the bus will will not start. Can anyone enlighten me as to what this is or what has happened ?

We have 2 very recently new batteries and it has a 100km drive a few weeks back - unsure what has happened here.
I have checked the batteries with a multi-meter and all the readings I get are over 12v. There is enough power to check all the lights, indicators, wipers etc.

......no idea.

[donu]

on my civilian, If you pull the handbrake on the buzzer should stop, I dont believe the buzzer actually has anything to do with the glowplugs.
As for not starting, are you getting any solenoid "click" and dashlights etc dimming If yes, then I would have thought Batteries.
I allways start mine with the handbrake on, so wonder if there might not be an ignition interupt, as some vehicles do with having to have your foot on the brake pedal.

[tedheath]

It will be the low vacuum alarm

[ThePog]

It will be the low vacuum alarm

Thats what it is on mine.

[Comber]

Appreciate the time to respond. I have had a quick google but not sure what you guys means by a low vacuum alarm - can you give me some more information ?
Is this what I should be understanding;

https://en.wikipedia.org/wiki/Manifold_vacuum

I should also mention that I probably panicked with the 'no start' thing. It starts fine and the alarm disappears when ignored and the bus starts no problem.
When I then turned it off again, and on again, there was no alarm.

So no idea what the air raid siren was for.

[Nut17]

As others have mentioned, it will most certainly the vacuum warning buzzer. There is a vacuum pump on the engine that provides energy for the braking system. When your bus has been sitting for a while without being driven, the vacuum will be lost. When you start the engine it will take a short time to create sufficient vacuum to switch off the alarm. It is all working as it should.

[donu]

interesting
On my Civilian the buzzer comes on if you have the handbake off when turning the ignition on/starting, It doesnt make any difference if you have vacume or not.
I can start run switch off and immediatly restart and the buzzer sounds [only for a short time]
I tend to think that as both my brakes and clutch use the vacume assist and it is quite hard to hold them in and working until you do get a vacume [if needed], so it is more a safety thing of having to use the handbrake. Otherwise there is something wrong with my vehicle [not unheard of]
In my case it doesn't matter, as I have always [in all vehicles, even autos] used the handbrake to hold a vehicle stationary and not rely on the gearbox to perform that function, therby neccesitating the need to disengage the clutch when starting.
I will caveat that with the fact that when parked on an incline, I do engage first/reverse as a failsafe.

[Nut17]

The hand brake integrated with the vacuum warning buzzer may well be a bus safety thing. I suspect that BUSRSQ will be able to shed some light on this.