im looking for an expert on mecedes off road diesel engines. i hope im posting in the right spot. i run a 99 wirtgen wr 2500 ( a 30 ton machine that tears up roads) it has a 12 cyl. benz diesel in the neighbourhood of 18 liters and was good for 650 horse when new. of late i've been having alot of probs with the fuel system. the mechanics at work cant figure it out, personally i think the injection pump (bosch) may be on the way out, the motor only has 2000 hours on it, and i ve been told if i can find someone to fix it i can hire them. i work basically in the toronto ontario canada area. any help would be great.
thx. craig

 

well i dont know much about benz diesels as i have never worked on one, but what exactly is going on that you think its fuel problems? hard starting? no power? i mean it could a few diff things other than an ip.

 

well i figured out its definatly drawing air into the fuel system because in the moring after i start it it will run fine for a couple of mins but then will start to slowly die out and i have to use the priming pump to get all cyl fireing again. and sometimes when i bring the machine down from high revs ( the motor works on a switch, idle or full fuel) it will idle fine for a min or two then slowly start to die out again. but where and how im going to find the leak im not sure?

 

This is just a stab in the dark because I cant say I know anything about Mercedes diesels - but I would look at the fuel lines...dont just look at them - feel them. I say this because on a Cummins, the lines develop very small holes and let air in yet not leak fuel. The lines essentially rot from the inside out and it lets air into the fuel system, which causes it to lose prime. Not sure this is the problem but I think I would start by replacing all fuel lines.

 

thanks doc ill start with that, this motor is really similar set up to my 12 valve, it has no computer, inline mechanical bosch pump, (other that the 12 cyl) i guess with the age of it (1999) the lines could be going. is there anything safe i could spray on the lines and listen for a change in sound to the motor to see which lines are gone or is replacing them only way to see if they are gone.....and if they are that would prob be the reason im getting the power loss up top (still get full revs) and the priming issues.

 

well if its like the 12v cummins and has the fuel pump before the ip then you should feel the lines and air being sucked in, i guess just spray water and you might be able to see it being pulled in. look at lines that are near metal or the frame where they might rub and such.

 

okay guys i will check that and get back to you and let u know how i made out