dozer

howdy guys, I could sure use some help on this.... My truck is a 1985 Mack Mid-liner MS300P 8.8L turbodiesel 6-speed. - Engine is: MIDR 06.20.30 SN 01418LE 204 hp @ 2300 rpm - IP, Injection Pump; Bosch PES6P-120A320RS417 I bought this in the winter, spent some time getting my little knuckleboom and bed mounted, and am now working on getting her 'up to speed'. The only 'mechanical' problem I've got is that the truck chokes/stumbles and smokes a white cloud for the first 10 minutes when cold. It acts as though the IP timing is very retarded. So, after looking at the adjustment-procedure in the service-manual, I figured it'd be pretty easy to pop off the inspection-plate and advance the pump 2-3 degrees and see if that reduces the smoke. But the IP shaft/hub setup on my engine does not match what's shown in the Mack manual.....at all ! The book shows a simple hub and gear....with 4 bolts to hold them clamped together...and 4 slotted bolt-holes in the hub....to allow adjustment of the hub/pump relative to the gear. But on my engine, it's not a simple hub-gear at all.....mine has some kind of mechanism (I think) on it....two big pieces spring-loaded toward each other (toward the center)......maybe some kind of RPM-based centrifigual timing-changer ? I managed to get the camera in there and get a pic... http://www.oregonstone.com/mack3.html I also posted a pic of the picture printed in the manual.....showing what the book thinks is there...lol. In fact, the inspection-cover itself doesn't even match the book. The manual shows a 4-stud setup....but mine has 6 holes....with socket-head bolts going into threads tapped in the timing-case cover. Note: there was a 6" diameter steel disc on the nose of the shaft, in front of the mechanism that's visible in the pic. This disc was held on by a big snap-ring, and rotates freely when in place. I removed the disc to get this picture. Has anyone seen this mechanism before on any PE pump on any brand of engine/truck? I'd very much like to get hold of an adjustment procedure from a service-manual before I even begin to mess with it. Note; the "Mack Custom Manual" binders that I got with the truck include an "Engine" section for model MIDS 06.20.30......and the data-plate on my engine says MIDR...rest of number the same. But everything in the book has matched my motor exactly...until now... Richard

Well, the injector -was- bad.....and having it reman'ed did make it so that cracking the injection-line loose on that cylinder now reduces RPM and adds roughness just like the other 5 cyls. BUT....it did not change the white-cloud-when-cold situation at all. Looks like my IP is very retarded for some reason. Since it's a new subject, I'll start a new thread for it... Richard

howdy Rob, Mine also still has the lead seals on the IP-screw wires. Odo says 250K, but speedo isn't working; so I'm not sure of the actual miles. On the other hand, the guy who owned it for the past 10 yrs only used it once a week for local delivery....and for the most recent 3-4 yrs, it just sat. So it's probably 300K or less. Interesting that you mentioned a "funny noise".....can you describe the noise at all? While I was working on it the other day, while it was idling, I noticed an occasional 'tink' noise from (I'm pretty sure) the engine. I was on the right side.....up near the front....I tried to localize it, but couldn't really pinpoint where it was coming from.....but it sounded like the front of the engine. Wasn't a constant or regular (i.e. every stroke) type of noise....just occasional...semi-random timing, 1-5 seconds apart.....very 'light' kind of noise, but quite 'sharp', if that makes sense. If rain doesn't stop me, I'm hoping to get the injector on #2 pulled today, so I can see if that's causing my dead-hole. Richard

howdy Rob, Thanks much for the helpful info. Is yours also the 8.8L (538cu) version?.....same model# as I listed in first post? Yeah, while reading through the manual one day, I was getting a bit frustrated until I realized that they simply -had- to be numbering the cylinders 'backwards'. One I assumed that, then everything made sense... Hopefully I won't have to get into resetting the timing from scratch. Although I do plan on 'turning it up' a bit in the future, my only goal right now is to get all six holes firing right again. I found it interesting that there isn't any Anti-puff unit on this IP. But then I considered that they've got this engine turned so far down, that this reasonably modern 8.8L DI is only putting out 205hp.....and I realized that the fuel-rate must be so damn low, they don't -need- an anti-puff... Essentially, it's so far turned down that it's not really taking advantage of the turbo....not really using all that extra air. Runs real clean though! For the near future, I'll just turn it up until it barely starts puffing, and call it good. But I'd be real interested in hearing the details from anyone who's added an anti-puff assy from some other P-series pump onto this IP. Because a serious fueling/power increase would probably warrant doing this addition. thanks again Rob.....and any additional notes or observations on working on this engine would be much appreciated! Richard

Has anyone here done any fuel-system work on the 8.8L Renault/RVI engine in the Mack Midliner? I have a misfiring cylinder (ID'd via cracking lines loose one by one), and I want to pull the injector and see what's up....and I'm wondering whether this engine requires the coolant to be drained before pulling injectors. The Hino 6-cyl in my excavator has a big warning-sticker on the rocker-cover; saying that the coolant must be drained before removing injectors. There's nothing like that on this Mack engine, and the service-manuals don't talk about it at all (at least, that I've been able to find so far). Also, has anyone ever had one plunger go bad in a PE6SP pump? I don't know that mine's bad, but when I was cracking the lines open, the line on the bad cyl didn't seem to 'blast' and mist the fuel that was spraying out from the nut and line, as much as the other cylinders did. By the way, I need a good primer-pump for this PE6SP. The lockdown threads on this plastic plunger are stripped. If you have a known-good one you'd like to sell; or know of a good discount-place to buy one, please email me! metal@fullwave.com thanks much, Richard

howdy guys, I'm fixing up an old heavy-spec Mid-Liner, and need some parts on a budget..... - TRUCK IS: 1985 Mack Mid-Liner MS300-T cabover tractor, mfgd 11/84 - Engine is: 8.8L, 538 cuin, Renault MIDR06.20.30 SN 01418LE 204 hp @ 2300 rpm - IP; PES6P-120A320RS417 , 450-30110B , 0 402 046 'X' 24 - Trans is: BDSL181, Mack# is T1060 PARTS NEEDED: - Shifter: "ball-socket" part that mounts to the floor-board....in new or like-new condition - Shifter: Set of ball-joints for the linkage at the tranny (6 speed BDSL181) - Dipstick for MS300-T - Fuel Tank Cap - Gas Pedal Mount; The bracket part that bolts to the floor - Engine Shutoff Cable - AFC aka Anti-Puff sub-assembly, like from a DT466 or 8.3 Cummins; to add to my PES6P injection pump - Seat Cushion: for stock driver's spring-ride seat - Manuals: Full Electrical Wiring Diagrams; Service Manual for Bosch PES6P Injection Pump - Gauges: Boost, Pyro.....used are OK if in good shape - LED Tail Lights; set of 4....standard 4" round ? I'm in SW Oregon.....and appreciate any help in finding these parts cheaply. Please email directly rather than PM.....PM's are real slow to handle over rural dialup. thanks much! Richard metal@fullwave.com