turckster

Numbers 1&2 look like the foot and check valves (treadle valve) #3 looks like an air operated windshield wiper motor #4 is the cab to chassis wiring block. Most major chassis to cab components are connected here.

When diagnosing this type of issue I install a gauge into the wet tank and a gauge into the unloader port on the governor. The wet tank is the signal source for the air governor. When air pressure drops in this tank then the air gov. dumps the air psi to the compressor and dryer purge valve so the compressor can rebuild the air psi. Once max psi is achieved the air gov. sends an air signal(system air psi) to the compressor and dryer purge valve. The air compressor unloads and stops building air and the dryer purges and dumps air within the dryer and line from the compressor. The purpose of the gauges is to see where the air loss is coming from. When the dryer purges, do you loose air in the wet tank or on the unloader signal? If you loose air psi in the wet tank I would look at leaking lines, bad check valves and so forth. Once the dryer purges there should be no air coming out the purge valve. If there is air coming out the usual culprit is a bad discharge check valve on the dryer. If you are loosing air psi in the signal line(unloader), Either a leaking line or fittings, bad purge valve or air compressor head. A bottle of soapy water and a quite shop will help a lot.

Two 12v batteries should be plenty for a '79 model RD. Some reasons for more batteries is if there are a lot of electrical components, if you have an automated type trans of some sort or all batteries(4) are 6 volt.

Code 6-2: Failure Mode Identifier (FMI): 0 (Data Valid, but Greater Than Normal), 1 (Data Valid, but Less Than Normal), 3 (Voltage High), 4 (Voltage Low), 5 (Current Low/Open), 8 (Abnormal) Parameter Identification (PID): P103 Message Identification (MID): 128 Circuit Description: The Turbocharger Wheel Speed (TWS) Sensor is an inductive sensor. When the engine is running, the turbocharger shaft rotates past the TWS Sensor tip and a pulsed voltage signal is generated. The Engine Electronic Control Unit monitors the frequency of the signal generated by the TWS Sensor to calculate the turbo speed. Code Setting Conditions: If the Engine Electronic Control Unit (EECU) detects an open, short to ground or short to voltage in the Turbocharger Wheel Speed (TWS) sensor signal circuit, the Electronic Malfunction Lamp (EML) will turn ON and blink code 6-2 will set. Code 6-2 will also set if the turbocharger wheel speed is not within the predetermined limits at a given engine speed. Location: The Turbocharger Wheel Speed (TWS) Sensor is located on the right side of the engine, mounted in the turbocharger. Normal TWS Sensor Parameters: The Turbocharger Wheel Speed (TWS) Sensor has a resistance of 638–1062 ohms. Additional Symptoms: Power is reduced if the TWS Sensor signal indicates shaft speed in excess of 112,000 rpm at sea level or 120,000 rpm at 5000 feet (1524 meters). Code 6-3: Failure Mode Identifier (FMI): 8 (Abnormal) Parameter Identification (PID): S250 Message Identification (MID): 128, 142 Circuit Description: The J1587 serial data lines are used as the standard communication link for on-board vehicle instrumentation and off-board service diagnostics and fleet management. The V-MAC® III control units broadcast data across the J1587 serial data lines to operate electronic instrumentation, the electronic gauge panel, and the Co-Pilot display, and to communicate with the ABS, Allison Transmission and Eaton Transmission control units, depending upon the vehicle model and options. The diagnostic computer communicates with the V-MAC® III control units through the J1587 Serial Communications Port. Location: The Serial Communications Port is located under the dash, to the left of the steering column. Code Setting Conditions: If either the Vehicle Electronic Control Unit (VECU) or the Engine Electronic Control Unit (EECU) loses communication through the J1587 serial data lines for more than 1 second, code 6-3 will set and the Electronic Malfunction Lamp (EML) will turn ON. The fault will become inactive if communication resumes for at least 1 second. If code 6-3 sets intermittently or is accompanied by other fault codes, check for secure connections at the 135 amp ground circuit breaker posts. The ground circuit breaker is located on the left side of the bulkhead.

I'd start with the most obvious, make sure all ground and positive connections are clean and tight. From the batteries to the starter, chassis grounds and cab grounds, ground relay. Also make sure your batteries are in good shape.

When an air compressor purges and looses air in the secondary tank you have 2 bad check valves. A bad check valve in the air dryer discharge and a bad check valve at the secondary tank inlet. When an air dryer purges, the air dryer discharge check valve protects the wet tank from loosing air psi since the air gov. signal line is plumbed into the wet tank. The wet tank supplies the primary and secondary and both have a one way check valve at the inlets.

The Fault is for soot level, the FMI:11 is critically high soot load/level. The conditions for the fault is high soot levels in the DPF. Possible causes: Aftertreatment injector is clogged and /or DPF clogged. If you don't have the Tech Tool program and its at level 4 warning you will have to take it to a dealer. More than likely the 7th injector (aftertreatment injector) is clogged or has a poor spray pattern and the catylist is face plugged. The 7th injector will have to be cleaned, the DPF assly disassembled, the catylist cleaned and hopefully the DPF filter is ok. Assembled back together, the injector adaptive factor reset and a manual regen performed.

ECM SPN 5392, Aftertreatment Diesel Exhaust Fluid (DEF) Dosing Valve Loss of Prime – MID 128 PSID 121 FMI 31:Aftertreatment Diesel Exhaust Fluid (DEF) pressure build up failure- Possible Causes: Empty DEF tankDEF filter cloggedDEF inlet pipe leak or blockageDEF pump assembly

Could possibly be a fuel psi issue, I have seen the fuel pump gears slip at times and cause the problems you describe. Best way to tell is install a fuel psi gauge, If fuel pressure is ok during the issue the it could be an egr problem.

It's not that bad of a job, quite easy actually. After removing the valve covers, remove the iinj. lines. You don't have to completely remove the lines, just move them back enough so they are a couple inches away from the injectors. Pull the injectors out, I use a small slide hammer(seal puller) with a 5/16 fine thread adapter on the end. Once out make sure all the tip washers are out-very important you have all 6 washers. Unless you had a leaking injector and a hole has carbon in it, I usually spray some brake clean into the injector holes and blow them out. Its best to use non-flammable type brake clean. Install the o-rings onto the injectors, only the top 2 groves are used-above and below the inlet, I use grease to hold the tip washer and lube the inj. o-rings. Using a 5/16 fine thread bolt about 4" long, screw it into the top of the inj., line up the dowel on the injector to the slot in the head and install the injectors. A lot of times they will pop into place pushing them in, sometimes you may have to tap one until it bottoms with a small hammer. Once in, snug the inj. caps, install the inj. lines and snug lines. Torque the inj. caps to 45 ft/lbs, then torque the lines to 30-35 ft/lbs at the heads, 25 ft/lbs at the inj. pump. While you are there you might as well adjust the valves. Valve adjustment should be .016" intake and exhaust should be .024". Check the valve cover, on some engines the exhaust is .028". Good Luck

If the engine has steel roller lifters you can re-use all lifters but the one(s) that failed(of course), On the ceramic roller lifters, it was Mack policy(under warranty) that only the failed lifters were replaced. But with customer pay we pushed to replace them all, I do not trust used ceramic roller lifters. Your choice on this, it is expensive to replace all the lifters. Other than fresh gaskets and seals, you should be good to go.

First I would check if the engine ecu has oil in the connectors, oil in the connectors can cause false readings/faults. With the valve cover off inspect the wiring insulation, if it is brittle and comes apart then you will need an engine harness. If all looks ok then I would replace the terminals as per the Injector Harness PDF above.

The engine breather filter is in a canister located at the right(passenger) side of the front cover. The canister is mounted to the front cover. Once you get the lid off the cover, use needle nose pliers to remove the filter element.

A Mack trans should work on all those engines. Bell housing bolt patterns should be the same. Only problems would be adapting clutch linkages and rear mounts-if equipped.

The inj. pump harness connector could be at fault, Check the terminals for signs of corrosion or overheating from poor connection. Have someone crank the engine while you wiggle the connector to see if the engine tries to start. if that's the case, clean the terminals w/electrical contact cleaner. Secure the connector to the holder using zip ties, keep the harness movement to a minimum. Good luck

An engine brake on an E-7 engine will not fit/work on an E-Tech engine. Another option, other than Jake Brake, may be the Mack Power Leash. You would have to check with the Mack parts dept. to see if your engine is compatible. I've heard the Power Leash works better than the Jake Brake, but how much or if its even worth spending the money on I couldn't tell you. I don't drive 'em, just work on them. One of the reasons for the poor performance of the engine brake is the smaller displacement of the Mack engine vs other engines. The Mack E-7/E-Tech is 728 ci where the Cummins 400 big cam engine is 855 ci. Good luck

A lot of the older E6 Mack engines had a main cap issue. Main caps 2, 3, 5 & 6 were the usual suspects. Usually when I was to overhaul one of these engines the first thing I would do was pull the pan and drop these main caps. Inspect the bearings for odd wear, checked the main cap and block mating surfaces for fretting and for cracks in the main cap bolt holes. If the fretting was bad (which would cause odd/uneven bearing wear) we gave the customer 2 options- reman engine or pull the engine for disassembly to have the block line bored. With a crack in the main threads it would be an reman engine. E6 engines with the main cap plates (2 & 3 - 5 & 6) didn't usually show this wear or not as severe. If you had the engine overhauled and the main caps showed severe fretting and had (a) crack(s) in the main bolt holes they should have stopped and informed you. Given you some options and explained the consequence of said options if you chose not to repair properly.

Need to know the fault, might be a 9-2 by what you describe. A 9-2 fault is loss of power while the key switch is in the on position. Check all connections-at the battery, starter and firewall, positive and grounds, including the ground relay. Good luck.

The only recall that I'm aware of for this chassis that is light related is for an updated headlamp wire harness that includes some relays to take the voltage load off the h/l switch. There are 3 possible wire harness types and the switch panel has to be removed to determine which harness you have. You can perform the recall yourself but I'd let the dealership do this.

Best test is to install the suspected ecu into a known good truck and see if the problem follows the ecu. If it does then you know the ecu is bad, if not then its time to start digging. Good luck

Do the valve covers and/or oil fill cap have a grey sludge like substance on them? If so you have a coolant leak into the engine. Usual culprit is leaking past liners because of an eroded counter bore ledge or leaking core hole plugs in the heads. Before you removed the heads you should have pressured the cooling system, removed the oil pan and valve covers to find out where the coolant was coming from. I'd still pull the oil pan and look for signs of leaking liners. Good luck

Depends on what year model e7 we're talking about here. If an e-tech I would look at the injectors, air in the fuel or fuel pressure. If an e7 (inline inj. pump) could possibly be TEM sensor, econovance timing actuator, injectors, fuel psi, possibly timing gear movement on camshaft, internal injection pump issue....... Good luck

New injection lines on the E-tech AI/AC engines only, all others you can reuse.

They need to do something with the TT2. As quirky as TT1 is, at least it works. TT2 feel like an unfinished program that was pushed out too soon full of bugs.

Its my understanding that the customer can hook up a hand held scanner to read obd only faults. Its a universal thing-volvo, mack, international, freightliner and etc. Now if you want to read manufacturer specific codes then you would have to purchase said software. Its set up that way so that the customer/owner can read and repair obd faults without relying on the dealer. I could be wrong though so don't hold me to this.