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pos

pos

Well-Known Member
Posts
3,685
Location
West Yorkshire
Hello,

I'm slowly making progress with my underpowered 200TDi. So far I have found a gaping hole in the fuel filler pipe, so my tank had been full of water and salt thrown up by my wheels (tank drained). I've replaced a dogey joint in the fuel line, swapped my lift pump (which had a failed diaphragm) cleaned my injectors and replaced my fuel filter. The bastard thing is still underpowered though. I'm narrowing the problem down to the fuel pump now however. When the turbo starts boosting, the pump isn't giving the engine any extra fuel. The union on the compressor housing that provides air to the waste gate actuator and the boost diaphragm pipe is clear and producing plenty of "puff". When I removed the top off my injection pump (boost diaphragm housing) I've found that there doesn't feel to be much air coming down the pipe when the turbo is boosting. The pipe is not split, or blocked however.

The boost diaphragm is in good shape with no splits or tears and I can push down on it to adjust the load on the spring without there being any stiffness etc (besides the tension in the spring of course). How do I remove the boost diaphragm and the eccentric pin from my 200TDi injection pump? Supposedly if you push down and jiggle it and then lift up it should pop out, but this is not the case. I have a feeling that the diaphragm is positioned in the wrong place or that the pin has seized with water being passed through the fuel lines. How would I free the pin up if it has seized and how would I know? Also, how much pressure (boost) should there be coming down the boost diaphragm pipe under load?

Is there anything obvious that I can check in the injection pump with regards to increasing the fueling as the boost increases?

Thanks for any help, this is a frustrating and ongoing problem!
-Pos
 
I know what you're saying, have you read the listing? cracked block! hope you don't have same problem has him! Good luck with it fella and keep us posted on what you find, i'm following this with interest as my landy seems to be suffering the same faults as yours from what you're describing, Last week I drained nearly 1/2 a cup full of water from the fuel filter, so now i'm wondering if my inj pumps ok!
 
The pressure in the pipe should be the same as the pressure in the manifold - however as the cross-sectional area or the pipe is much smaller, the actual force exerted on something (e.g. your finder) over the end of the pipe will be much smaller (but at high flow - BUT the turbo will have to be UNDER LOAD to make this happen!). However when this then expands into the diaphram chamber the pressure will again be the same, but as the cross-sectional area of the diahram is now much bigger the force on the diaphram will be increased, as long as the turbo can supply enough volume of air to keep the pressure up (which all things being equal it should be able to do) - This is how hydrolic systems get away with not blowing up the hozes when huge forces are put on the rams.

So basicly if you turbo is doing 0.75 bar aprox 10psi then you can work out from the size of the diaphram how much force will be exerted onto it.
 
dazzx10r said:
I know what you're saying, have you read the listing? cracked block! hope you don't have same problem has him! Good luck with it fella and keep us posted on what you find, i'm following this with interest as my landy seems to be suffering the same faults as yours from what you're describing, Last week I drained nearly 1/2 a cup full of water from the fuel filter, so now i'm wondering if my inj pumps ok!
Click to expand...

I hope it's not a cracked block! :eek: There's nothing there to demonstrate it being a cracked block mind. There's no loss of coolant and no crankcase pressure. I'm certain that this is related to the pin and the diaphragm eccentric inside the injection pump. If there's been the slightest bit of water in there, the pin that slides up and down the eccentric under the diaphragm may well have seized.

Does anybody know the technique for removing the diaphragm? I can pull at it and wiggle it all day and it wont come out. What am i doing wrong?

-Pos
 
Well I've had the diaphragm out this morning. The pin looks to be non existent. It sits in it's recess towards the front of the pump and only moves out about 1MM when the throttle is actuated, is this right? I expect that if there is air in the injection pump, the needle wont move out to its full extent, or does the movement of the pin have nothing to do with the fuel flowing through the pump? The bugger is still not responding properly but I did find the fuel filter was full of air AGAIN when slackening the bleed nipple. This now comes down to two components. The first being the fuel pickup pipe that sits in the fuel tank (that is also bolted to the top of the fuel tank), the second being the fuel line between the pick up pipe and the lift pump. I replaced the lift pump yesterday to no avail, so air is not getting in there. Does anybody know how much I can expect to pay for a new pickup pipe (in the tank) and the line between the pickup pipe and the lift pump?

Cheers
-Pos
 
pos said:
Well I've had the diaphragm out this morning. The pin looks to be non existent. It sits in it's recess towards the front of the pump and only moves out about 1MM when the throttle is actuated, is this right? I expect that if there is air in the injection pump, the needle wont move out to its full extent, or does the movement of the pin have nothing to do with the fuel flowing through the pump? The bugger is still not responding properly but I did find the fuel filter was full of air AGAIN when slackening the bleed nipple. This now comes down to two components. The first being the fuel pickup pipe that sits in the fuel tank (that is also bolted to the top of the fuel tank), the second being the fuel line between the pick up pipe and the lift pump. I replaced the lift pump yesterday to no avail, so air is not getting in there. Does anybody know how much I can expect to pay for a new pickup pipe (in the tank) and the line between the pickup pipe and the lift pump?
-Pos
Click to expand...

The pin should protrude out into the pump by about 5-6mm, when you take the diaphram out look down the centre into the pump and pull the throttle arm to full throttle and you should see the pin move. I followed the tuning guide link as above
Cheers, and mine feels excellent now:D
 
dazzx10r said:
The pin should protrude out into the pump by about 5-6mm, when you take the diaphram out look down the centre into the pump and pull the throttle arm to full throttle and you should see the pin move. I followed the tuning guide link as above
Cheers, and mine feels excellent now:D
Click to expand...

When I look down the diaphragm hole I can see the pin but it doesn't stick out :eek: When I adjust to full throttle it only moves out by 1MM :( Is the pin seized and if so, how do I fix the bugger!? I'v noticed that down the front side of the injection pump (timing case side) there is a bolt / cover level with the pin. Can this be removed to provide access to the pin?

-Pos
 
gee1599 said:
thats the same problem i had if you pm me your number i will phone you and tell you how to do it
Click to expand...

Well your advice has been priceless :) I whipped the throttle mechanism off and then removed the grub screw that covers the fuel control pin. It was half seized into the slot and it required a good shove with a screw driver to free it up. I've since cleaned it up with some WD40 and a bit of Carb Cleaner, it moves out to its full extent now and it does so quite freely too. Haven't had chance to take it for a blast yet mind. Just the air in the fuel to sort now and then we're all good. Thanks for your help.

-Pos
 
bustersbus said:
And ye'll have been takin' plenty of photies pos???;)
Click to expand...

'Fraid not (as usual). I haven't got a camera at the moment anyway. I was bought an 'Aiptek' HD video camera from QVC for Christmas last year, and it's been replaced twice since - cheap Chinese crap. I'm meant to be picking up a nice new Casio Exilm from Argos tomorrow :) I don't particularly want to take it all apart again to take a few pictures, but don't tempt me :D

-Pos
 
pos said:
'Fraid not (as usual). I haven't got a camera at the moment anyway. I was bought an 'Aiptek' HD video camera from QVC for Christmas last year, and it's been replaced twice since - cheap Chinese crap. I'm meant to be picking up a nice new Casio Exilm from Argos tomorrow :) I don't particularly want to take it all apart again to take a few pictures, but don't tempt me :D

-Pos
Click to expand...
HEHEHEHEHEE! Ye know ye want to:D:D:D

Not a bad wee camera those Exilims.... that's what a use mesel';) Really ought to get a new one as it's only the 5 mp and it's full o' all sorts of muck and oil from me garage:rolleyes:;):D
 
bustersbus said:
HEHEHEHEHEE! Ye know ye want to:D:D:D

Not a bad wee camera those Exilims.... that's what a use mesel';) Really ought to get a new one as it's only the 5 mp and it's full o' all sorts of muck and oil from me garage:rolleyes:;):D
Click to expand...

This is the one I'm picking up:
CASIO Exilim Zoom Exilim Zoom EXILIM Zoom EX-Z25 Compact Digital Camera buy online | Currys

Supposed to be getting mine from Argos mind but it went up by £10 on their website earlier and the black one has totally vanished from their website now :eek:

-Pos
 
pos said:
This is the one I'm picking up:
CASIO Exilim Zoom Exilim Zoom EXILIM Zoom EX-Z25 Compact Digital Camera buy online | Currys

Supposed to be getting mine from Argos mind but it went up by £10 on their website earlier and the black one has totally vanished from their website now :eek:

-Pos
Click to expand...

It's not a bad price fur that pos, just looked at the site ah got mine from a whiles back and it's the same on there.... except they're temporarily out of stock;)

http://www.pixmania.co.uk/uk/uk/rf/casio-exilim/1659__1
 
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