sn PAB06638 Engine SN MAE05872 AR No. (arrangement) 2870092 This machine has always started within 3 seconds of cranking the engine. Last month, I helped clear an old homestead in a newly harrowed field...VERY dusty work for 3 days, sometimes I could not see beyond the cab. Shortly after that, I was digging out our 70-year-old pond and the engine would stutter sometimes and sometimes just stall. I limped through a couple of days of that and then changed the fuel filter...it only had 246 hours on it, but a neighbor said he had a similar issue before and changing the fuel filter fixed it. My stalling did go away when I changed the filter (the change interval is 500 hours, but super dusty must have been the issue). I also changed both air filters...internal and outer. I was away from the farm for 2 weeks. When I returned yesterday, it took about 20 seconds of cranking before it fired up. I ran it for a while and shut it down, and it restarted fine...within one second. This morning, it took about 15 seconds to get it to start up. Later during the day, it would start fine if I turned it off and recranked within about 10 minutes. At one point, when it had been off about 2 hours, it did not start within 10 seconds. I took the bolt out of the top of the fuel pump and noticed the fuel about 1-2 inches down. I primed the fuel pump, replaced the bolt, seated the plunger, and it started in about 10 seconds. Is it losing its "prime"? Why is it hard to start after sitting for a few hours? Seems to be some kind of fuel issue. I did not crack the injector bolt after priming. Maybe that would have made it fire right up? Once it starts, it runs fine, good power. I expect it to be recalcitrant again in the morning. What should I be looking for? Would a dirty banjo bolt filter do that? If so, where is it?
It's very likely that when the engine is turned off, fuel from the low-pressure circuit flows back into the tank. The fuel injectors may also gradually begin leaking fuel into the return line.
If this happened right after you changed the fuel filter then I would suggest that you look closely at the seals on said filter to ensure that nothing got trapped, twisted, or cut during the replacement.
If the fuel filter is a spin-on canister type is there any possibility that the seal from the old filter remained stuck to the head when it was removed and you now have 2 seals in there.?
Had same setup on a Cat 966D wheel loader that would not fill the filter, I changed out 2 check valves and all was good after that. Simon C
Thanks for the input, all. Good things to check...possible old filter residue and those check valves. It started fine this morning...no priming, within one second. A few hours later, it started stuttering again. I had to prime it and bleed injectors. A few times when it stuttered, I found I could feather the controls and the RPM's slowly came back up...then I could work for 30-45 minutes before it happened again. I assume it slowly re-primed itself, and I could work awhile. I have the CAT tech coming in the morning. He's been a good resource when I reach my limit, so I think he will puzzle it out. I'll let you know what happens.