Any Car/ Diesel mechanics out there?

Homer J

Got a problem with my astra van. It's a bugger to start in the morning, once it has been started it has no problem starting all day, until i leave it over night. It's as if the fuel is drying out or going back to the tank and needs to be pumped through?

I did the basics, check battery, change glow plugs. don't think its the injectors as it has no problem when it gets started.

Is there some type of non return valve that stops the fuel sucking back to the tank etc?

Any advice would be good.
Thanks

markos1963

I had this problem a few years ago with a motorbike, turned out to be the valve clearances were out. When I adjusted them no problems at all.

paulbricey

Have had same problem on an old Orion 1600i and it turned out that the retrun spring in the fuel pump outlet had a fault that let all the fuel drain back....(same symptoms you describe). I don't know whether diesels use same recyle but there should be a pressure control kick back from the diesel fuel pump back to the tank to maintain pressure at the injector rail -> guess if this goes wrong the pump loses primed fuel and takes an age to pull fuel up the suction ....

Smokin Joe

Might be the glow plug relay.

Fixed Wheelnut

Usually the non return valve is built in to the High Pressure pump, not sure about Astra's but usually modern high pressure systems have an electric lift pump in the tank.

First check is to check the fuel system for leaks that might be losing pressure.

Check the low pressure side of the fuel system pressure to see if the lift pump is working.'
DO NOT OPEN the High Pressure side if you don't know what you are doing

Another cheap test is to clamp the return and feed lines when you switch it off at night and unclamp them just before you start it to prove it is fuel pressure lost.

Do you get any smoke when starting that might indicate glow plug faults?

Cheshley

How much fuel is there in it?

No, not as daft a question as you may think..... I have a 1998 Vauxhall Omega Turbo Diesel and they have an inherent problem whereby the pipe that drops from the lift pump into the bottom of the fuel tank splits and allows air to be drawn through. It only seems to be a problem when the fuel level drops below 20 litres tho.

nicklouse

Homer J
what do you mean nby a bugger to start in the morning?

wont crank? cranks a lot? fires but coughs and will not go until the phlegm is clear...
starts but chucks out white "smoke" or black "smoke"

more info needed. Oh and is it a turbo or not.

Homer J

Thanks for all the info guys.

Fixed Wheel, i'll try clamping and check for leaks. It does smoke a bit when first started.

Nicklouse, It cranks over fine, no splutering. Chucks out white smoke when started. It's a 1.7 TD

Fixed Wheelnut

White smoke is unburnt fuel so could be a glow plug problem, not usually a problem in the summer warm months though.

nicklouse

Fixed Wheelnut wrote:

White smoke is unburnt fuel so could be a glow plug problem, not usually a problem in the summer warm months though.

+1

check the plugs are on long enough.

balthazar

+1 Glow plug relay. Test the glow plug circuit to check it's getting power.

dobbo75

Sounds like your injector seals are leaking!

To check this is the case, get the car started as normal (lots of cold cranking), then clamp the flexy hose (leak off pipe) that comes into one from all the injectors. (NB, don't drive the vehicle with the pipe clamped).

Turn off and leave until the next morning. If it is the injector seals, the old dog will start up straight away when cold.

Doing this prevents the fuel leaking away and air getting into the system, that's why once it's started and all the air has gone, it's ok.

Failing this, have you checked the feed to the glow plugs? or fuel filter housing for air leaks etc?

It's quite a big job if it is the injector seals :roll:

Homer J

Thanks dobbo, i'll give it a try

Chaz.Harding

White smoke = Water (steam) - think headgasket. Possibly.

Blue smoke = oil

BLACK smoke = FUEL...

Hope this helps!!

As for your problem... Could be the non-return valve. Sounds likely. Or your glow-plugs aren't working. Just because you changed them, doesn't rectify a fault before them (IE, not getting any power to begin with)

Doesn't go far to explain white smoke tho... Sorry!