JoeH

What model truck are you running? RD? DM? The engine may be a little longer, but it is longer towards the front not the rear. The front engine mount and fan assembly are more compact to account for length difference.

Fuel shutoff control? Is it a cable shutoff or air solenoid? On a mechanical truck if it won't start then you aren't getting fuel....

Just read it over, you'd switch from an em6 to an e7-454. You'd need to swap transmissions too, which may affect trans mounts and would definitely affect driveshaft length.

What year and model is your truck? With the right donor truck you could pick up much of what you'd need. Mack used a lot of components over and over across multiple models and decades. What trans do you have? Might be prudent to switch to an EM7-300 if your current rig is a maxidyne.

Which joint is "worn"? The forward one that mates to the pitman arm is adjustable, my dad just adjusted one of ours.

Saw this old iron on vacation in the Scranton region. Cabover caught my eye, was rewarded by a couple other gems taking a doze.

Sounds like curiosity saved the dog... Great find! Makes sense that a blown engine ate the turbo. We should have picked up on that tidbit and thought it through a bit better.

My E7-350 peaks at 35 psi boost. If think a 400 would do at least that.

I'm stumped on what afc stands for; is this the puff limiter system? I was thinking maybe the puff limiter system was hooked up wrong

The rule on adjusting Mack valves is "follow the book to the T"

What are you working on? Probably fuse #42 is loose for the EECU.

My Jake does the same on my 95 e7-350. Always get at least one head working on high, usually don't get the "low" setting head working ever.

The other possibility is you're low on coolant, and for some fluke reason 1500rpms seems to cause a dip in water level, triggering sensor...

In the event you don't have a crack, figure the charge air cooler system is good for 35 psi. Don't leave it on for too long if it's not leaking.

Charge air coolers like to crack. You should see 35 psi of boost. Get a couple 4 inch PVC pipe end caps, put an tire valve stem in one, and clamp one end cap into each rubber hose on the charge air cooler. Hook up your tire chuck to the valve stem on the one cap and listen for leaks. My '95 E7-350 had a nice big crack down the front right side of the charge air cooler. Went from 1100+ degrees on the pyrometer at 22psi boost to -900 degrees and 35psi boost.

Let's start with basic. 2 sensors trigger the shutdown alarm. Oil pressure and coolant level. Replace them both. The coolant sensor has a problem "wicking" coolant along through the sensor to the EECU causing pins to rot out on the EECU. Maybe your coolant sensor is failing. I think there might be 2 oil pressure sensors, one for the EECU and one for the gauge. I think. Joey Mack can correct me, and describe their locations.

Finally made time today to look into this oil leak... There's about a foot or more between the crank damper and the radiator so we figured we could do the timing cover without pulling radiator. Got damper off, hub seal was dry. But the 3 bolts on the driver side that hold the engine mount pedestal to the front engine cover were hand loose! So we torqued them back up to 70 ft lbs where they belong, and we'll see if the leak diminishes at all. Between all our schedules right now and being in the middle of our busy season it's hard to shut down half the fleet for three days to do the front cover properly. Hopefully the leak is reduced enough to hold off to the winter...

Could be oil too. Is it solid or liquid? Oil will float on water. If you have a bad head gasket or oil cooler then oil can cross over into the coolant.

If you don't have a dash switch up next to the ash tray then you have a peanut style automatic power divider. It requires at least one wheel to spin on each axle before you're "stuck". Not exactly sure how to interpret your particular situation you found yourself in, but I'm guessing your power divider was engaging and you had traction on your forward drive but not as much on the rear, so you had some weird tire actions. If you have the dash switch up by the ash tray then your power divider is manually turned on/off. To use this style you have to stop all wheels, flip switch on, then try going. One of my trucks has this style, I tend to reserve it to get myself unstuck rather than using it to get stuck. If that makes sense.

Also I think the "571" digits will be your part number differential between the different HP ratings. Seems you indicate your "571" part number is different from the 400's part number. This you probably don't have 400hp injectors.

Factories typically put paint marks on during assembly to indicate they've checked/torqued bolt down to spec. Could be all that is. If it's a Remack engine or was rebuilt by someone in the past it could be the reassembler's Quality Check mark.

Not familiar with vmac ii, but an old endt676 we had had a 5th gear air valve on the transmission that'd allow the fuel rack to open up all the way

Hope ecm solves it. Any time I check batteries I check resting voltage, then have a helper try cranking it while I'm watching the test voltmeter. My car battery started being unreliable the past couple months. Voltage always tested good, but it was losing cranking amps for some reason. Left me stranded a couple times before I ponied up for a new one.

Bad batteries?... EECU won't turn on with low voltage, I forget what the minimum voltage requirement is. If your batteries are toast or alternator died then I could see you lose EECU power and also lose crank... But I've only got experience with the one computer truck. Our other trucks are mechanical.

My mr688 would crank but not start. I'm guessing yours is the same because you are getting enough power to the key to give you the 9-2 code. If yours won't crank then you may have a power fault somewhere else, maybe the ignition itself.