4JG2 fuel issue??

[aussiemate]

Hi Folks,
I have a 1994 Isuzu Mu 3.1 with a 4JG2 motor.
I've had it for about a year and it has an issue where sometimes it will not start. It started when I parked it at a mates place overnight up a hill. It would not start in the morning. Rolled it down on the flat and mucked around for a bit but ended up getting a tow home. Coming off the tow truck face first then sitting for while it started no problem. But now it can be parked on level ground and it will do the same thing, but could be fine for a day, a week, a month. I replaced the fuel filter, now its ten times worse. I have to pump the hand primer...it will start, but to keep it running I have to sit in the seat revving it or keep pumping the hand primer. It idles like a pig. The guy at the auto parts store (an ex mechanic) reckons its probably an air leak in the Hand primer. What do u think? All hoses tight on it. I don't want to replace that to find it makes no difference.
Its service is up to date like oils, filters etc. I'm sure the fuel system needs a proper bleed but I'm not exactly sure how.
Obviously short on cash at the moment, otherwise I would be putting it into the shop.
Any help would be appreciated. I know to someone it will be completely obvious but this is my first diesel and I don't have clue

[Dinger95]

The only thread I recall seeing was over on isuzupup, http://www.isuzupup.com/viewtopic.php?f=36&t=12231 about how to refurb that hand primer pump.

Edit:
This also sounds like it may be helpful information. http://www.clubisuzu.com/viewtopic.php?f=23&t=3884

[geeves]

Air leak is most probable cause.
possible places
o rings on fuel filter
leak at filter drain
leak at any of the fuel hoses
leaky seal in injector pump
First check would be to ensure the 2 orings on the filter are seated correctly and that the filter drain is closed fully
Then temporarily change the pipe from the filter to the pump with a piece of clear tube. Bubbles here will eliminate half the system.
Bubles mean look at filter/pump/inlet pipe to filter. No bubbles mean either you got lucky and thats the faulty pipe or an injector pump fault. Do replace this clear pipe with original or proper fuel hose.
My money is on an issue with the filter because it got wore when you changed it

[aussiemate]

Thanks for the replies.
I will try some of these suggestions out for sure and let you know how I go.
Another thing maybe worth mentioning is how thirsty my Mu is. Best I get is about 14l per 100klms. This is a mix of hwy and around town. Put it in 4wd and it's just disgraceful. Its completely stock. no lift and 31's. It is an auto which I spose doesn't help. Using zero fuel at the moment tho coz not going anywhere haha.

[MUVIT]

had a similar problem with the wizard.
It was geting to the point of stall when you took slowed down.
& idle was all over the place.
Adjusted fuel & ilde screw to live with it.
Constantly priming filter to get it to start.
The Problem was the Plunger seal for the hand primer (above fuel filter) was causing the air leak.
Stole the Hand primer fuel filter housing off the MU & Problem solved.

Can you re seal the Isuzu Wizard/MU hand primer filter pump?
Mine looks heaps diferent then the 1 in the link above.

[geeves]

The one in the link was decently butchered. He ground the flange off to open it and made a pair of rings to bolt it back together.
In USA parts like this are hard to get so they have to go further in the repair. Here we can just go down the wrecker and grab one. Even pajero and surf ones fit but the filter number might change.
My wizard has been doing this to a lesser extent as long as Ive had it. Starts fine but if cold may miss terribly from about 5 seconds after starting until its given a small rev. (not nice pulling onto the road knowing that the gas peddle will be sleeping for the next 10 seconds)

[MUVIT]

Maybe you can get em new aftermarket?
Earthmoving equipment....... bobcats , mini diggers & forklifts?

[aussiemate]

Bloody hell it's hard to get parts for a Mu
However, finally got a new hand primer, put it in and she's purring like a kitten!!
The kit I got was a new primer, filter and sediment trap thing. Anyone in Brisbane looking for Diesel Spares, you should try Rocklea Diesel. There's a guy there named John who owns a Mu himself. He was a friggin life saver!!
Thanks for your advice gentlemen!

[geeves]

I hope you offered him free membership of here.