Rough Running LJ70

[AlexDukes]

Hi Everyone,

I hope you guys can help! I live in France and purchased a LJ70 2.4 TD (1990) to do some off roading and for getting around in the winter months.

At first, the car had no issues at all, although I would say that it seemed to lack power when going up hill, a necessity when living in the mountains! I would usually end up with a pile of traffic behind me as I was unable to get above 30 mph.

Driving around town seemed to be fine.

Then after a while the car started running rough, the engine rocking around all over the place, almost like it was only running on 3 cylinders, lots of smoke belowing out from the exhaust and a stench of diesel.

The car now doesn't want to idle and often stalls unless you give it some gas.

I have noticed that if I can get the car running and I give the fuel bladder a squeeze, the engine seems to behave.

The fuel filter and bladder looks like it is new.

Any ideas would be greatly appreciated!!

Thanks

 

[Ben Stratford]

You could try checking all fuel lines from pump to injectors are tight Alex. If air is getting it it will show similar symptoms

 

[outdoordan]

Blocked or semi blocked fuel line from tank to engine compartment can also cause similar. Disconnect feed from tank to filter and blow back up it to clear crud. If it's a minor blockage and you blow using mouth/lungs you may feel it clear. You can also use an air line to do same.

 

[outdoordan]

Change fuel filter anyway... it should only be a few euros from Norauto.

When you fit new filter prime it with neat injector cleaner.

Should help clear any crud between filter and injector.

 

[AlexDukes]

Thanks Ben, I checked the lines and they seem to be tight

Thanks outdoordan, I will try and have a look at that tomorrow, weather permitting!

Probably being a little bit thick, but where is the fuel pump?? or is it all sucked through by the injector pump?

 

[AlexDukes]

Also, if there is a blockage info the fuel line, why do i get the big clouds of diesel smelling smoke coming from the exhaust?

 

[yota_lj]

Check into the tank, surely the float in the tank has algae or isn't totally free
it's a common issue on lj

 

[AlexDukes]

**UPDATE** So, I managed to get some time to blow through the fuel pipes, the pipe from tank to filter seems fine, however, I did find a complete blockage in the return pipe from engine to tank!

I tried clearing it with air and the blockage wouldn't budge, I have had to resort in removing that section of piping and CUT the pipe where the blockage is, even with the piece in my hand, I tried removing the bloackage with a coat hanger and still been unsucessfull!.

So I need to buy some fuel pipe tomorrow and some jubilee clips to replace the cut out piece of pipe.

QUESTION, will this fix the problem!!?????????

 

[outdoordan]

could be one of your injectors is dying or has died. never going to hurt so buy a second hand set, buy a set of the correct nozzles and get someone to build you a nice new set then keep the set you have fitted as spares or stick them on the bon coin

 

[outdoordan]

might well fix it

 

[AlexDukes]

So the dying injector has blocked the return pipe with shards of material???

Correct nozzles?? How do i find out which ones are correct?

Am i better off buying a brand new set?

 

[outdoordan]

i dont know how the return pipe got blocked, the only way of knowing for sure is to inspect the debris from the blocked pipe.

i was just thinking out loud about the injector. they do occasionally break but they usually make quite a racket.

unburned fuel at the exhaust and rough running makes a malfunctioning injector a possible cause.

It might be the blocked return is causing one or all of the injectors to misbehave... i cant remember exactly how it all works... the return is just a low pressure dribble iirc... not sure how it would interfere with injectors but instinct tells me it might.

if it was me i'd change fuel filter and fill with neat injector cleaner... run it and see if it has an effect.

go to the partsouq website, find the part number for your injectors and it should be easy to buy new nozzles from there. loads cheaper than buying new injectors. i might be wrong... injectors for that engine might be easy and cheap to find.

 

[outdoordan]

here's your answer:

https://www.oilburners.net/threads/what-happens-if-your-return-line-is-plugged-up-or-clogged.58600/

 

[AlexDukes]

Thanks Outdoordan,

I managed to remove the crud from the cut out piece of pipe and put the crud in a plastic tub and tested it with a magnet to see if there was any metal fragments inside, to which there was none.

I replaced the cut piece of pipe with some new fuel line and a couple of jubilee clips, refitted to the car and gave it a try.

A several turns and jumping a dead battery and lots of pumps of the bladder, it came to life and seemed to run much smoother.

Gave the car a test drive and seemed OK, but no marked improvements in the performance side of things, after a short run (5 mins) the car felt like it wanted to stall and it did, I managed to restart it but the car didn't seem to want to stay running.

Got home and tried letting the car just idle on the drive. it seemed ti idle fine but gives what I would describe a noticable misfire once every 10 seconds ish.

If I let it idle for a while and then blip the throttle, it revs slightly then the engine dies.

Don't know whether it means anything, but whilst driving, if I put my foot down, the green turbo light comes on at roughly 1500 revs and then the red comes on at roughly 2500 revs and stays red until I either change gear or let off the accelerator??

Any ideas??

 

[Shaun]

There’s a filter in the tank, I pulled mine out once as it was doing the same as yours and it was completely covered in slime. Cleaned it and it sorted the job out.

 

[AlexDukes]

Where is this filter? I tried removing the cover that is as the back / centre of the car and undid the 6 screws underneath to reveal the fuel level sender, nothing else?

Have I got to lower the whole tank??

 

[StarCruiser]

Try running it from a can into the fuel filter Alex. If it’s no better the problem isn’t with your fuel lines/tank filter. Another trick is to put a section of clear fuel hose in line after the filter and look for air bubbles in it while it’s running.

Injector cleaner (Wynns Eco Diesel is a good one) can be used neat as suggested.

To have a blockage in the return line is most odd. Was the truck unused for some time before you bought it? Does the fuel seem slimy?

 

[AlexDukes]

OK, thank you STARCRUISER, I will buy some clear pipe today and try and find some Wynns Eco Diesel, easier said than done in France!

I have had the truck for 3 months or so, no idea of previous history although the engine bay looks imaculate, doesn't mean anything though!

 

[StarCruiser]

Running from the can with clean new diesel should show improvement if it’s fuel or tank/pipe related. Another thing to check is whether the float in the fuel filter is working to show water and if not whether there may be water in the base of the fuel filter. Try draining some off into a clear jar, you should see a definite line between fuel and water if there is.

 

[AlexDukes]

Any tips or tricks how to run it from a can? Just a long pipe into a fuel can??