Hey guys, need some help here. Bought a ,93 HDJ81 cruiser which has developed a slight flutter or noticeable miss in the lower revs. Goes away at around 1800-2000 rpms. Have had a heap of work done attemping to isolate and remedy but still the miss remains. Done so far......
All injectors done, new nozzles etc, pump pulled off and new driveshaft, transfer pump, d valves, d/v springs etc. all done by reputable diesel and turbo crowd that come highly recommended. Compression test come back ok so they suspect tight valves....the miss remains and it still goes away after 1800-2000rpms.
1000 kms after getting truck back the pump drive comes off resulting in bent valves, broken cam, stuffed head. Apparently the locking tabs were never bent over to secure the bolts. Back to mechanics who immediately took full responsibility without any issues. While the head was off I got them to pull the Pistons and put in a new set of hoops and big end bearings. They footed the bill for all work on top including a refreshed head, guides done, valves done, new cam, belt tensioner etc. all back together and still the frigging miss remains. Suspecting the injectors again I pulled them myself and sent them to a reputable fuel injection specialist for piece of mind. He found a variation of 15 bar between the respective pressures and went right through them setting them all to spec so I could definately eliminate them as the cause of my miss. Put them back in but still the miss is there. So....... Not the injectors, not tight valves, not rings or Pistons (compressions all good although new rings still need to bed in more) who's got some clues???....back to the injector pump perhaps?
Incidentally......went for a drive the other day, bloody gutless struggling to get up a very minor rise. On the driveway. All good once I got enough revs and the turbo kicked in and it then drove well....until i had to stop at any intersections. Then again, very, very gutless until the revs picked up a little and the turbo kicked in. Very scary struggling through an intersection with the boat behind. Read the forums and found a thread stating same symptoms caused by faulty diode in alternator??? Maybe some relation between alternator output at idle and low revs??? Anyhow, knowing I had a battery on the way out, I replaced both batteries with new ones and the gutless symptom disappeared? I have no idea if this could be related to my miss but perhaps one of you knowledgable chaps may note some significance?
All injectors done, new nozzles etc, pump pulled off and new driveshaft, transfer pump, d valves, d/v springs etc. all done by reputable diesel and turbo crowd that come highly recommended. Compression test come back ok so they suspect tight valves....the miss remains and it still goes away after 1800-2000rpms.
1000 kms after getting truck back the pump drive comes off resulting in bent valves, broken cam, stuffed head. Apparently the locking tabs were never bent over to secure the bolts. Back to mechanics who immediately took full responsibility without any issues. While the head was off I got them to pull the Pistons and put in a new set of hoops and big end bearings. They footed the bill for all work on top including a refreshed head, guides done, valves done, new cam, belt tensioner etc. all back together and still the frigging miss remains. Suspecting the injectors again I pulled them myself and sent them to a reputable fuel injection specialist for piece of mind. He found a variation of 15 bar between the respective pressures and went right through them setting them all to spec so I could definately eliminate them as the cause of my miss. Put them back in but still the miss is there. So....... Not the injectors, not tight valves, not rings or Pistons (compressions all good although new rings still need to bed in more) who's got some clues???....back to the injector pump perhaps?
Incidentally......went for a drive the other day, bloody gutless struggling to get up a very minor rise. On the driveway. All good once I got enough revs and the turbo kicked in and it then drove well....until i had to stop at any intersections. Then again, very, very gutless until the revs picked up a little and the turbo kicked in. Very scary struggling through an intersection with the boat behind. Read the forums and found a thread stating same symptoms caused by faulty diode in alternator??? Maybe some relation between alternator output at idle and low revs??? Anyhow, knowing I had a battery on the way out, I replaced both batteries with new ones and the gutless symptom disappeared? I have no idea if this could be related to my miss but perhaps one of you knowledgable chaps may note some significance?
