Yet another ZX TD not starting properly thread!!!

VLL · Post by **VLL** » 05 Dec 2005, 13:07

My ZX TD has for the last year or so not been starting very well, hunting for the first couple of seconds then sounding like its on 3cylinders for about 30seconds and pumping out loads of grey smoke, but with the colder weather recently this has been much worse.

Firstly, all the glow plugs have been changed to Beru ones about a month ago which made no difference, the leak off pipes have been changed, again making no difference.
The glow plug timer works as you can hear it click off about 30seconds or so after the light has gone out if you dont start the engine.

The primer bulb i suspect could be leaking back as if you pump it till it goes hard and leave it about 10seconds its soft again, although doing this before starting from cold makes no diffence to starting.

Now this is where things get confusing.... if the car is parked facing downhill it starts and runs really roughly, if its on the flat its a little better and if its facing uphill its a bit better still!!!!!

This is really starting to bug me (and probably the neighbours), so if anyone has any ideas of what i could try doing next i would really appreciate it.

Dave

ralph · Post by **ralph** » 05 Dec 2005, 13:36

Have you used biodiesel or similar recently? It lifts muck out of the tank and this quickly clogs up the fuel filter, making starting difficult.

James.UK · Post by **James.UK** » 05 Dec 2005, 13:36

Hi Dave.

From your description it sounds as though you may have two seperate problems,

the hand primer should stay hard, you need to find out why it doesn't... The other problem is why isnt it igniting the fuel it does get..

It sounds as though your car is drawing in air instead of (or as well as) fuel, Check all the fuel supply connections are tight and fitted properly, as a temp test put some thick grease round the joints and see if that helps, you can clean the grease off after the test.

It may need a new hand pump, the valve inside may be allowing fuel to run back to the tank.

The grey mist is a puzzle?

that is unburnt fuel.. So try the battery to glow plug test and see if the car starts better.. It could be the glowplug relay-timer unit that I have just had trouble with.. If it is, get one from the scrapyard, only takes 5 mins to get it off and not much longer to fit it in your car.. Nice clean easy job for a change.

Post by **RichardW** » 05 Dec 2005, 14:10

Check the valve clearances... you'll probably find the exhaust valves have closed up leading to a loss of compression when the engine's cold. If it's an air leak problem then pumping the primer and immediately starting should produce a nice clean start - which in your case it doesn't. Break out the feeler gauges!

Post by **Peter.N.** » 05 Dec 2005, 14:31

Yes, I agree with Richard, it sounds as though you have low compression on one or more cylinder/s. As the valves, wear/bed in, the gap closes until there is no clearance. Not an easy job as it means taking the camshaft out at the least. If it starts OK eventually, I would leave it untill the warmer weather!

jeremy · Post by **jeremy** » 05 Dec 2005, 14:49

I note what you say about the starting being better when the nose is higher than the tail. How much fuel do you keep in it?

VLL · Post by **VLL** » 05 Dec 2005, 15:27

Thanks for all your replies, I am going to try a new primer bulb and fuel filter, them try to make sure i dont have any air leaks anywhere.

Richard, your comment about low compression caused by the exhaust valves not closing is interesting as just over a year ago I had the head gasket done and the head resurfaced, and if i remember correctly the problems started not long after that. The head gasket is fine though, uses no water or oil.
I have however felt that it has been down on power a bit and at first thought it might be the pump timing that was out which was causing the bad starting and slight loss of power, could the garage have fitted the new timing belt and knocked the pump out a tooth maybe?

Thanks again for all your help.

Post by **Peter.N.** » 05 Dec 2005, 18:58

If the timing was out I think you would have noticed it immediatly. If the pump is retarded by one notch it would very difficult to start and would run very quietly and smoked. If over advanced, it would start but be very noisy and it would have had some affect on the performance. It could be that the new gasket was thicker than neccessary and has lowered the compression.