I own a 1988 4.2 non turbo. - with 560,000 on the clock -
which I have owned from new - it has become very hard to start.
I have had the 6 Glow plugs replaced and double checked that they are all working correctly.
I have the Pre Heat timer on maximum time and always give it a double (or treble) go.
The problem is worst when the vehicle is cold and been sitting for a couple of days.
I was wondering ?? is it possible for the fuel to drain back to the tank - and require time to purge it through to the injector pump ???
The engine just winds on the starter motor with no sign to ignition .... (as if there is no fuel present) once it fires it is away with non problems.
It's almost as if there is no fuel present to fire up the engine ???
As I said once the motor fires up she runs like a bird, with plenty of power and No misfiring - and warm starts are no problem.
Is there a non-return valve or similar that could be letting the fuel drain away from the injector pump ??? needing time to 'pull' the fuel back up to the pump ???
Any help would be appreciated.
I have had the vehicle into the Auto-electrician who could easily duplicate the problem but could not fix it. - just to tell me its not electrical ???
Could it be lack of compression with 560,000 on the clock & motor untouched ??? Its just that the vehicle runs so well once its running ????
Any help or suggestions would be appreciated.
(the Injector Pump was fully overhauled a few years back when we had the problem with the Sulphur Free Diesel causing seals to leak)
Look forward to some suggestions.
Thanks guys.
Brendon..........
RE: 1988 - 4.2 Non Turbo - Hard to Start When Cold -
Posted on 25-09-2008 20:39
Is it possible for the fuel to drain back to the tank...Highly unlikely in this case, the engine would run extremely rough and blow a lot of black smoke as it begins to run, you noted it runs smoothly when it starts.
There is only one electrical connection on your injector pump, for the fuel solenoid, make sure this is getting power to it when you turn the key on. Your auto electrician has probably checked this but make sure, no power to this solenoid will stop the engine running. It could be a faulty solenoid also.
Lack of compression. Also unlikely given how well you say the engine runs when it does start.
I would suggest ringing around a few diesel specialists in your area.
Tony
RE: 1988 - 4.2 Non Turbo - Hard to Start When Cold....... -
Posted on 02-10-2008 20:01
There are two valves in the lift pump. If you get dirt under one of these it is possible to lose fuel pressure until the diesel pump drags fuel from the tank.
Couple of easy tests.
Park the truck with the nose downhill amd leave it for a day or so with the tank full.
If ot starts easy then you can start looking for problems in the fuel system.
One that I know of that was causing a truck to be hard to start cold was the fuel return line in the head had sprung a microleak under one of the retaining banjo bolts. It only caused a problem when it was cold. It would shrink and leak enough to get air into the system which made the truck hard to start.
Diesel Australia in Underwood found it and sorted it for a couple of hundred spons.
RE: 1988 - 4.2 Non Turbo - Hard to Start When Cold....... -
Posted on 09-10-2008 22:55
could be low compression needing the motor to turn over a bit faster so it fires.try starting with another battery connected to your battery to see if it starts quicker.
could be injectors not spraying correctly making it hard to start.