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Everything posted by turckster

  1. There is an inconsistent signal between the cam and engine position sensors. The most likely cause is the flywheel ring has moved. You should be able to unplug one or the other sensor and the engine should run, may take some cranking to start though. There is a procedure to check if the notched position has moved on the flywheel but right now I can't find it.
  2. This is a diagnostic flow chart for fault SPN:5394/SPN:4094. Even though your fault is only 4094 it is the same thing basically. Practically anything can cause the 4094 fault from contaminated DEF to plugged EGR diff. psi sensor ports. The flow chart will have you test/check each system to verify it is functioning properly. snm 13- 022 archive spn5394 fmi17 diagnostic.pdf
  3. The IMT (intake manifold temp)sensor are on pins J2 80 and 61. The sensor you are checking is the aftercooler outlet temp sensor (pins J2 84 and 67). The IMT sensor is located in the intake near the center (next to the VGT control valve). Knowing the fmi will help in what direction you need to perform diagnostics.
  4. The only place that the two systems come together is the injector cup area. A small imperfection or wear in the o-ring could easily let fuel past but hold off coolant pressure. Did you check the fuel tanks for coolant?
  5. Uses lots of oil and has white smoke.I'd say it's plum smooth wore out. At least with info provided.
  6. Most cam issues for a mp8 are most likely from either poor maintenance (no valve adjustment) or improper valve adjustment. Mack/Volvo had some issues with the rocker arms but by your year model that should have been fixed. Seen some issues with the reman injectors, hopefully Mack is on their ass about improving the quality. I'm currently overhauling a 1996 e7 engine (level 3 overhaul) in a R model (cotton module hauler). Everyone in the shop was saying the truck wasn't worth it and the owner was crazy to spend that kind of money. The truck is in awesome shape, they take great care of their equipment. It is a mechanical engine (non V-Mac) with no emissions other than a LDA (puff limiter), it's a no-brainer in my book. I'm not a fan of modern emissions but it is what it is and that's what I get paid to fix.
  7. Could possibly be a cracked injector cup at the body to tip area, seen that many times. Could also be a leaking egr cooler, worst case could be cracked head. I don't think a bad water pump would cause pushing coolant unless the engine overheated and cracked the head or damaged the egr cooler. If the upper radiator hose is hot to touch and the lower radiator hose is cold the you may have a water pump issue(vanes spinning on w/p shaft). Even if the water pump is determined to be bad its not the reason for pushing coolant.
  8. When replacing injector(s) you should program their calibration codes and perform a learned data reset. That way the engine ecu relearns idle characteristics and so forth to adjust for a smooth idle. Or, let the engine idle for a while with all accessories turned off so it can re-adjust/learn accordingly.
  9. When you torque the inj. hold downs to 15 ft/lb, 180 deg, back off to 7-8 ft/lb, torque to 18 ft/lb and torque turn to 90 deg that averages 45-50 ft/lb. Therefore there is no way when backing off a bolt that you are going to get 60 ft/lbs. Several years ago there was a recall that require retorque/check of MP8 injector hold downs and the torque spec was 45 ft/lbs. It may be that is the problem, not tight enough. But, what do I know, I'm not an engineer, just a dude that fixes their mess ups.
  10. Use to replace injector cups once a year and some more often on the same trucks it seemed until the most recent install tool came out (88800513). But, I think its also very important that the injector bore, tip bore and conical seat area is clean and pit free (seat area). Proper torquing technique is very important as well. I've seen some techs in our shop zip right through injector replacements only to see them come right back several months later.
  11. If you have air bubbles in your return fuel you will have to determine where it is coming from. Most likely it is injector/cup issue. If there is no air in return fuel and is not hard to start then you have a problem elsewhere. You can reuse injectors but it depends on the injector to cup wear pattern. On the conical tip of the injector if it has a uniform thin wear pattern around it and there are no signs of soot/carbon above it you can reuse that injector. If that wear pattern is thick and thin or there are signs of soot/carbon above it then it is not reusable. Any time an injector is removed the cup gets replace , can not be reused.
  12. The cruise and dash light circuits are not related. The cruise will stop working because of- bad /mis-adjusted clutch switch, service brake switch or that circuit activated, Fuse, short/open in circuit.
  13. There are 2 different fuse blocks (that I know of), I only have a picture of one, hope it is correct.
  14. There are 2 types of electronic viscous fan clutches, the Borg-Warner and the Behr type fan clutch. The Borg-Warner is huge and probably what is on the engine. As stated above, unplugging the B/W fan clutch should engage it within 30 seconds according to service info (usually happens immediately). If the engine is equipped with the Borg-Warner fan clutch and it does not engage then it must be replaced and updated to the smaller Behr type fan clutch and kit. It also needs to have the EECU software updated.
  15. I never said it was a bad transmission, I just don't care for it and I don't think it would be a good trans choice for the OP"s question. BTW, I doubt I'm alone on how I feel about the Allison trans.
  16. Personally, I would go for the Mdrive. The least expensive rout would be a manual trans but with it comes routine service(clutch adjustment). The Mdrive requires none of that but, as pointed out above, is expensive come clutch time. I'm not a fan of the allison trans. A few oil field companies tried to run some in their fleets locally and they were just a pure pain in the tush. Plus, any automatic trans robs horsepower.
  17. The Ishift/Mdrive have a diaphragm clutch which is non adjustable. Volvo and Mack are pushing to have customers spec the AMT transmissions and I think they have been a pretty good trans. Most drivers that I talk to really like them.
  18. The speedo sensor has an ohm value, the circuit does not have voltage other than what the sensor itself creates when the truck moves. Depending on type of sensor, the ohms should be approx 100-200 ohms, typically around 150-170 ohms measured either from the sensor itself or from the VECU.
  19. I'd check the bellhousing to make sure the mount flange still has some taper--hasn't been run loose. Also looks like it may need an input shaft by the looks of the throw-out bearing area. If the bellhousing is in bad shape then the only good thing its good for is parts.
  20. Some coolant reservoirs have a burn hole in the pressure cap/overflow side that can cause coolant loss. Pushing coolant can also be caused from a bad air compressor head, leaking egr cooler, bad injector cup and cracked head.
  21. After idling for about 5-10 min check in each fuel tank where the fuel returns inside the tank. If there is bubbles in one or both tanks then the cause is most likely injector cups. To make sure, check the small plastic cap at the fuel filter base (next to the primer pump) is not wet from fuel leaking around it. If so, the problem is the cap---leaking o-ring sucking air into system. You can get a replacement cap from Mack. If ok make sure 7th injector air purge "t" check valve isn't leaking air back to fuel system. Remove the fuel line from the "t" fitting, turn key on and there should be no air coming out "t" fitting. Some '07 emission engines had the air purge line, some didn't . If both above items look ok then most likely you have injector cup issues.
  22. Never seen that particular situation. Is 10% the highest duty cycle the 7th injector gets or does it get higher? Is aftertreatment fuel psi low across the board? I've had to replace the shut off valve because of low fuel psi.
  23. I believe before you go to all the trouble to raise the engine high enough to remove the egr cooler that you can remove the egr valve without breaking bolts or stripping threads in the manifold. If that happens (which happens a lot)then you might as well remove the turbo and so forth.
  24. Sounds like the cam position and crank position sensor connectors are crossed. The ecu see's excessive speed and shuts off the starter.
  25. Slowly and carefully run the knurling thread tool through the tip and use the threaded extractor to remove the tip.
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