4jb1t fuel pump prob??

[muskie]

hey guys, thought i had a oil leak, so stripped the guards from underneath my 89 bighorn and degreased. it is now clear that i have a fuel leak not oil, it was dripping from the pump rolling down the side of the engine picking up oil residue and crap and thus falsely leading me to believe it was oil on my lovely new driveway.

anyway, the car has random smoke problems, one day she will run great but kick out black smoke even when not revved hard, other days she will still run fine but hardly show any signs of smoke...

am i right in thinking the two probs are related.

am i looking a the big dollar to fix, i know nothing about diesel pumps but am reasonably mechanically minded
being an engineer..

cheers

[geeves]

Is it running down the outside or rear of the pump or is it comeing out near the cam belt. If the first there is a way to fix without fully rebuilding the pump. Ive sent you an email with pictures etc that were suplied by Garth in Auckland.The smoke might be related but more likly either injectors need cleaning or oil problem. If injectors a bottle or your favorite injector cleaner should do the trick if its useing oil then fitting a catch can might help.

[mudgrip4]

Speaking of Garth, he gave a good tip some time back re leaking diesel pump, which may be relevant here. Said he used some 'Moreys diesel smoke stop and injector cleaner' and the leaking stopped.

I have a friend with a 93 3.1 which began to leak a few months ago - getting pretty bad. Remembered Garth's experience and told the dude to try this Morey's product. Result - after a month the leak has stopped and the seals seem to have softened up are doing the job again. Very good news esp when pump seals can cost $1000 to do.

So bear this in mind Muskie - if it's a pump seal issue, and not easily replaced, the Morey's product is definitely worth a try.

Mike

[geeves]

Morreys is a good injector cleaner as well. Worth a crack. Only problem with it is it doesnt come in small bottles which makes initial purchase quite expensive but it lasts a long time.

[muskie]

thanks guys that is helpful, will look at these ideas this week.

i do have a question tho, why are diesel pumps soooooo expensive to get sorted or rebuilt? there only seals arnt they??

[muskie]

oh yes it already has a catch tank fitted, well a plastic bottle with a 1'' pipe going in it, is this a bad sign, it was on it when i bought it.

[geeves]

Only a bad sign if it is catching lots of oil. Some people fit them as a matter of course. I will fit one to mine when I think it is nessecsary. Its only done 200000 so could be a while yet.

To rebuild a pump fully it has to be taken off. This takes 4 hours at mechanics rates. Everything has to be washed in clean diesel as you go and the whole pump is assembled imersed in clean diesel.If you have to go to this much trouble then you might as well measure everything and replace whatever needs to be done hence the cost. Even doing the seals that can be done in place takes time as Mr Isuzu didnt intend his vehicles to ever need work so designed them so work couldnt be done. Just doing the top and accelerator seals on mine took 4 hours and cost $300 includeing $26 woth of genuine seals

[muskie]

in the 6 months i have owned the truck there has only been a light residue at the bottom of the bottle and i meen really light, if is to be believed the engine has only covered 148,000kms, no reason to suspect otherwise. turbo good and pulls well but oil pressure guage is all over the place. i have been told to use 10/30 oil in the 4jb1t engine as apposed to 15/40 which i have been using?? what do you guys use??

[geeves]

both will be ok but do use a good quality diesel oil. I have used the Repco diesel and wont be useing it again but have had good results from Castrol ctd,caltex Dello400, and Valvolene diesel extra. Some people have developed oil leaks useing Dello Probably just makes existing leaks worse. My engine did leak more with it but it leaks anyway. Oil pressure gauge should read 4 cold and vary anywhere from 4 with a few revs on to just over 1 at idle once hot. Nissan Safaris will read 0 at idle once hot

[muskie]

thanks again, it was repco oil i bought origionally and i will change it shortly for a better quality brand.