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Discussion Starter #1
1996 T4 2.4D.

Struggling to start in that: starter turns over fine - but takes ages to slowly fire bit by bit before building.

I have checked:

Battery - drops only to 10.5V under load - and it was new last year

Glow plugs - power is getting to them - checked with multimeter on the fuse in the side of the engine bay.

Fuel filter - drained it. Then changed it this afternoon.

I did have a little leak in one pipe attached to the fuel filter - but I changed the patch on it with new PFTE and tape just in case - there was no change.

Relevant facts:

the longer I leave it after running, the longer it takes to start. I think it may be leak somewhere, but I don't know where to start looking.

It does seem to stumble sometimes when it is running and under load. But it is very briefly indeed.

I did an oil and oil filter change last week. There seemed to be a bit of an oil leak, so I went back in and tightened the filter again - just a tiny tickle with a 30mm spanner - as I couldn't get a firm enough grip on it with my hands the first time round.

I would be really grateful for any input!

Thanks,

Simon
 

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Common fault locations if fuel

Leak in the pipe from the fuel filter,
Leave in the connector onto of the fuel filter,
Leak at the pump

Relay be it the glow plug in or can’t Reiner the other one.
 

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1996 T4 2.4D.

Glow plugs - power is getting to them - checked with multimeter on the fuse in the side of the engine bay.
test the gp's;)

this means removing the busbar between each gp then using either a multimeter (resistance test) or +12v & seeing if there's a 'spark' when touching power to the gp's terminalI:

gp failure is the most common cause of non-start (or slow start) on tractor engines like the 2.4T:


Rich
 

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test the gp's;)

this means removing the busbar between each gp then using either a multimeter (resistance test) or +12v & seeing if there's a 'spark' when touching power to EACH gp's terminal individuallyI:

gp failure is the most common cause of non-start (or slow start) on tractor engines like the 2.4T:


Rich

edited to add clarityT:

Rich.
 

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Discussion Starter #5
Common fault locations if fuel

Leak in the pipe from the fuel filter,
Leave in the connector onto of the fuel filter,
Leak at the pump

Relay be it the glow plug in or can’t Reiner the other one.
Wow - that was quick. Thank you.

Leaks in the fuel pump connector and pipes to and from it - I've just changed the fuel filter - had them all off - and they seemed to be fine. I couldn't see any fuel at all, and they seemed to be in fairly good nick - so I reckon no air going in.

The glow plug relay is dodgy anyway and a bit hit and miss, but it doesn't sound like that, and I bypassed the relay anyway, and it made no difference. I suppose it could be the actual glow plugs, but I've had the relay not work before so I know what starting up without them sounds like, and it's not like that.

Is there another relay? Is that for the fuel pump? That might be worth a look.

Leak at the pump is also an idea. I'm assuming that the pump sucks fuel through the fuel filter from the tank, and injects it into the engine at the same time... I will have a look.
 

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Discussion Starter #6
edited to add clarityT:

Rich.
Tractor engines. Love it. I hear lots of tractor engines - mostly when they are stuck behind me going up hills.

Guessing open circuit is what I am looking for. Then again, I've had glowplug issues before, and it doesn't sound like that.
 

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The valve on the top of the fuel filter is a common thing to fail.
Yes there is another relay that is a common fault but I can’t remember which it is, sorry it’s been a few years since I’ve owned a t4
 

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I remember when changing the glow plugs on the t4 I had it started having issues starting and that was because the nut on the end of the bar connecting the plugs had worked lose
 

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Sounds like air leak in the fuel lines.

I't draining back fuel slowly when stopped - which is why it takes longer to start the longer it is left.

There is a clear section in the fuel feed pipe for the sole purpose of spotting air bubbles in the lines - the no 1 cause of poor running.

All the previous suggestions are good, not sure if anyone mentioned the fuel feed fitting on top of the tank (accessible under van cab floor mat) it can crack and let air in.

Try parking on a slope and see if the problem occurs when you park facing uphill or down or both ways.
 

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Another common point of leaks is the fuel sender in the tank. a crack develops in the feed tube letting air in, but only if your tank level is low (1/4 full maybe, can't quite remember).
 
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