110 fuel problems - still

All,

110 Defender CSW 1990 2.5l diesel (just pre 200TDi)

This should be simple - but as ever it aint!

I have a problem that with the fuel cap fitted (it is the correct one I
have checked) I get excessive pressure in the fuel tank and the effect
of fuel starvation on the engine after a period of running at reasonable
speed.

As a first test I removed fuel cap and the fuel starvation problem went
away.

I then made my fuel cap "vented" by drilling a hole in it! This is also
fine except just after when I have filled up the tank and the diesel
spurts out the hole.

It is a Landrover fuel tank. There is a drain plug, a take off to the
lift pump, the filler neck and a breather in parallel (although this
breather is attached below the fuel cap) so it can't "breathe" with the
fuel cap fitted (I assume it's just there for when you are filling with
fuel).

Any suggestion as to what is happening? As this is positive pressure it
means that a significant amount of either fuel (or air) is being
returned to the tank. Is this a symptom of a failing injector pump? I
know that I have a leaky injector (as I get a lot of smoke and rough
running on idle) could this be a factor?

Can you suggest any fuel injection experts in the Wiltshire area
(Trowbridge to be precise)

Cheers

Peter

In message <[email protected]>, Peter
Sheppard <[email protected]> writes
>All,
>
>110 Defender CSW 1990 2.5l diesel (just pre 200TDi)
>
>This should be simple - but as ever it aint!
>
>I have a problem that with the fuel cap fitted (it is the correct one I
>have checked) I get excessive pressure in the fuel tank and the effect
>of fuel starvation on the engine after a period of running at
>reasonable speed.
>
>As a first test I removed fuel cap and the fuel starvation problem went
>away.
>
>I then made my fuel cap "vented" by drilling a hole in it! This is
>also fine except just after when I have filled up the tank and the
>diesel spurts out the hole.
>
>It is a Landrover fuel tank. There is a drain plug, a take off to the
>lift pump, the filler neck and a breather in parallel (although this
>breather is attached below the fuel cap) so it can't "breathe" with the
>fuel cap fitted (I assume it's just there for when you are filling with
>fuel).
>
>Any suggestion as to what is happening? As this is positive pressure
>it means that a significant amount of either fuel (or air) is being
>returned to the tank. Is this a symptom of a failing injector pump? I
>know that I have a leaky injector (as I get a lot of smoke and rough
>running on idle) could this be a factor?
>
>Can you suggest any fuel injection experts in the Wiltshire area
>(Trowbridge to be precise)
>
>Cheers
>
>Peter
>
>


Is it a turbo ?

If so it will be a split in the turbo boost diaphragm on the top if the
injection pump. This is allowing boost, created by the turbo, to
pressurise your fuel tank.

I have seen engines rev out of control with this problem too.

Good luck
--
Marc Draper