T 25 TD starting trouble

[DalesRover]

Hi

I have a 1987 T25 TD with an AAz engine fitted. Starting has been fine until recently.
Now it is being a pig to start in the mornings. The garage has fitted new glow plugs and a new glow plug relay. No improvement.
They have tested the electric supply to the glow plugs as well. That's OK.
I have tried turning the ingnition on and off several times, sometimes it improves things - mostly it doesn't.
Now very frustrated and in danger of getting a disabled thumb from riving on the key!!

Has anyone any suggestions? (Once started it is usually OK for the rest of the day).

Christine
(Please keep it simple - I am not a mechanic )

[California Dreamin]

Hi there,
CI engines (compression ignition) rely on the high compression of a diesel engine, to generate the heat needed to ignite the diesel fuel. However, when cold much of that 'initial heat' is lost into the cold metal surfaces of the cylinder head so the engine needs 'help' in the form of 'glow plugs' which 'pre-heat' the combustion chambers.
So in short:
If you have good compression
New glow plugs
A relay that brings on those glow plugs for a reasonable duration (3 - 5 seconds this time of year...roughly... but longer in the winter.)
Fuel supply....without air ingress (has any part of the fuel delivery been messed with recently?)
Air supply (a clean air filter)
Good cranking speed and battery power for those glow plugs.

It should start! lol

I'd be checking on the 'timed' feed to the glow plugs. (making sure the relay is bringing on those plugs for a long enough period)
And carrying out a compression check.
Has the AAZ got fuel pump advance? one for the diesel boys?

Martin

[chrisbeck]

Hi
Mine had a broken conecting strip that goes between the glow plugs. Initialy you couldnt see it, but it was cracked where the nuts tighten it down on the glow plugs, which ment only one plug was getting power to it.
Maybe worth a quick look.

Chris

[DalesRover]

Thanks everyone. I'll get those things checked out.

Christine

[DalesRover]

Successful outcome at last.
The trouble seems to have been a problem of air getting into the fuel system overnight resulting in fuel dropping back down into the tank.

Garage fitted a non-return valve on the fuel system yesterday and it started at the first turn of the key this morning.

Perhaps this information might help someone else at some point.

Christine