LVC

Member
Hi all,

I've a 1986 90 with a Defender 200tdi and for the last couple of years I've been noticing a increasing drop in power - to the extent now that she struggles to tow a loaded twin jet-ski trailer back up the launch ramp.

To date I've:

- Changed the timing belt
- Changed the lift pump
- Cleaned the air filter (there was about a 5ml teaspoon's worth of black oil in the filter > turbo pipe).
- The fuel pump was tweaked to provide more fuel but this hasn't changed the "lack of power" issue - possibly increased the smoking one though.
- Just ordered a new fuel filter

On start up and under load it'll smoke black (quite heavily at times). When towing the trailer up the ramp as I lift the clutch the revs will struggle and drop (I first thought that this was a clutch issue but now pretty sure it isn't - still have a complete HD clutch to fit if needed).

The Turbo has very little play in it and hits roughly 1bar on the cheapie gauge I added to the dash.

There's no significant oil loss - I check regularly and changed oil and filter earlier this year.

I believe that black smoke is a over-fuelling issue and am now wondering whether there's an issue with the injectors (blocked or knackered) - they are the originals and I've no idea what the true mileage of the engine is but I've had her 14 years and know they've never been cleaned or changed in the time with me.

The car starts first time every time cold or hot and has no issues with tick-over or anything else except this lack of power and heavy'ish smoke.

Top speed with no trailer has not changed.

I'm thinking to change the injector nozzle tips for new ones - is this as good idea or is it better to change the whole thing or should I be looking at somewhere else for the problem?

Any help, ideas or advice will be greatly received :)
 
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Hi all,

I've a 1986 90 with a Defender 200tdi and for the last couple of years I've been noticing a increasing drop in power - to the extent now that she struggles to tow a loaded twin jet-ski trailer back up the launch ramp.

To date I've:

- Changed the timing belt
- Changed the lift pump
- Cleaned the air filter (there was about a 5ml teaspoon's worth of black oil in the filter > turbo pipe).
- The fuel pump was tweaked to provide more fuel but this hasn't changed the "lack of power" issue - possibly increased the smoking one though.
- Just ordered a new fuel filter

On start up and under load it'll smoke black (quite heavily at times). When towing the trailer up the ramp as I lift the clutch the revs will struggle and drop (I first thought that this was a clutch issue but now pretty sure it isn't - still have a complete HD clutch to fit if needed).

The Turbo has very little play in it and hits roughly 1bar on the cheapie gauge I added to the dash.

There's no significant oil loss - I check regularly and changed oil and filter earlier this year.

I believe that black smoke is a over-fuelling issue and am now wondering whether there's an issue with the injectors (blocked or knackered) - they are the originals and I've no idea what the true mileage of the engine is but I've had her 14 years and know they've never been cleaned or changed in the time with me.

The car starts first time every time cold or hot and has no issues with tick-over or anything else except this lack of power and heavy'ish smoke.

Top speed with no trailer has not changed.

I'm thinking to change the injector nozzle tips for new ones - is this as good idea or is it better to change the whole thing or should I be looking at somewhere else for the problem?

Any help, ideas or advice will be greatly received :)


I'm sure someone can give you a bit more info than I can but I'm sure your meant to have your injectors serviced, a poor injector could cause some of the problems you have talked about in your post above.
 
Thanks chaps for the replies.

All hoses were changed for new silicone ones earlier this year so all good there;

Had a bit of time today so I took out (from the engine) all of the injectors (fuel hoses disconnected prior) and gave them a quick surface clean with some carb cleaner I had available. All were pretty much sooted up (could hardly see the spray holes) and all went back in nice and clean. Fired her up and had blow back on the injector nearest the bukhead - removed and re-tightened and all good. Went for a spin and black smoke on startup (normal I believe) but noticeably less on hard acceleration. Difficult to tell if under load it's improved things as the jets are winterised and they and their trailer are not accessible - but going up a steep hill and accelerating hard in 3rd and then 4th produced no major smoking (it used to). Also tried with the air box to turbo pipe disconnected (this is the only non-silicone pipe on the air system) and no difference so pretty sure it's not got an air issue via the hoses.

Tappets I haven't checked yet but the car has always had the usual diesel tappet noise but as you say probably worth checking.

I'm thinking of buying an injector cleaner and adding that direct into the new fuel filter (when it arrives) to give them an overdose of cleaner - good idea or bad ?

Smoking is not the big problem (I expected it to smoke more with dialing up the fuel pump) it's the lack of power and with the turbo spinning at 1 bar the minor mods on the fuel pump I wouldn't have thought it would have caused a power loss - I could be wrong of course ;)
 
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Cleaning the outside of the injectors will not make any difference.
How did you tweak the inj pump?
Start simple and work your way up, pump timing, easy to check, plenty of vids on youtube
Check valve clearances bound to be a lash cap or two missing.
Then maybe get you injectors serviced, you can check them yourself but do need to be careful.
 
check the wastegate on the turbo too, if its stuck open you wont get boost properly, youd still get to max boost, but youd not be getting much pressure until you got there.
 
Thanks again for the advice.

The pump had the top taken off and the diaphragm "turned" to a higher level - I believe, it wasn't me that did it but I think that's what he said that he did.

I'll check the tappets - seems easy enough.

and will also check the waste gate.

I know cleaning the outside of the injectors won't have changed much but was hoping that some of the spray carb cleaner cleaned out the outlet holes - it seems a bit less smokey since I did this but it could just be wishful thinking ^^
 
Bit of an update:

- Played with the wastegate and can get a drop to .7bar and up to 1bar depending upon how much I screw the actuator in. Put it back to 1bar.
- Wastegate moves freely - I didn't take the turbo apart but doubt the wastegate is stuck open.
- Changed the fuel filter and added injector cleaner.
- Front cylinder injector has a slight air leak so have ordered new washers - judging by the state of the injectors when I removed them I'm wondering whether they've had an occasional air leak as well - would this cause my issues I know it def won't help?

Also in changing the fuel filter I noticed that it was only 1/2 full - is this normal ?

And finally, I changed the lift pump last year when I started to have this problem but never managed to "feel" the pump lever becoming hard to pump (had the same with the old one) and am wondering whether the new lift pump fitted was a duff as the old one and that this is still causing my problem.

The air bleed on top of the filter never seems to have anything more than a little bit of air forced out of it and def no diesel.

Help please - I'm going around in circles ^^
 
There have been some poor quality replacement lift pumps about,some say you are better off overhauling an old type one.Check fuel is coming from the tank ok and that line is not blocked.
 
Fuel lines are good and I've removed the wire filter on the end of the hose in the tank (to eliminate this as a potential blockage).

If I open the air bleed on top of the fuel filter and then operate the lift pump handle manually I expected to hear a bit of a air hiss as fuel was forced into the filter, but hear nothing at all - is this normal ??
 
nah i dont think you would hear anything mate.

mines actually suffering a similar issue at the minute. Suddenly went gutless, ive replaced the lift pump etc as you have.

Have you checked the sedimentor? (thats on my list)
 
You should be getting a good glob of fuel coming out of fuel filter with every stroke of the lift pump once the air has gone. It is possible to fit lift pump with it's operating cam the wrong side of the camshaft, then it won't work.
 
Thanks chaps.

I will check and clean the Sedimentor -won't do any harm to give it a clean anyway.

From what I've found and read, and as per tottot's message I defo think the lift pump is not doing what it's supposed to. Will check tomorrow by removing the outlet pipe and cranking the engine - theory is that if I get a real squirt of diesel then OK, if it dribbles then not OK. Does the actuator arm go under or over the camshaft - just in case it's a silly mistake that I made on fitting it?
 
Ive got a similar problem. Infact sounds identical.

Havent found my cause either. Yet to check pump timing, thats on my list of jobs.

I neither get any resistance from manually pumping my delphi lift pump on my 300tdi. However, if i remove the IP wire, and crank the engine with the filter bleed screw cracked off. It ****es out of there. So guessing the lift pump is working. Its only a few months old
 

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