DavidT

Thanks guys. Sounds like I am stuck pulling the entire front fenders and all now. Man o man thats a lot of work just to change the two chrome pieces on the grille shell. I think I will suggest a new chrome one with the more modern mounting arrangement when I go back together with it. I am off now to figure out how the fenders bolt on and will let you know how it goes. This project has been fun so far and of the three Macks we have this is my favorite one but now I think I may like the EG a little better.

I am working on a 1958 B model and need to remove the grille shell to replace the chrome on it. I have looked all over and found there are four bolts at the top and about 6 inside on each side of the grille. My problem is the ones on the side are impossible to get to. I have looked at it from every angle and found no logical way to get the grille off. I considered taking the head light panels out but there too are more bolts that can not be accessed. What am I missing here guys? There has to be some kind of order or something to get this thing off. Thanks.

The most obvious to check is the clutch switch. Check it for adjustment make sure it is right. The next thing to check is a problem that I have seen several times in my shop. On the rear of the truck there should be an external ground wire that bolts on to one of the bolts that holds the bar on that holds the tail lights. I have seen that wire broken or just loose cause this very problem! Simple fix just a pain to track down.

X2 on the breather hose. I found one just like that a couple years ago.

Before you do anything grab that big round plug that goes to the injection pump with the truck at idle and wiggle it around. See if your engine doesnt start to stumble and carry on. If it does, you found your problem. All of them that I have seen like that had to have the actual plug ends replaced because the pin locks in them had worn and were letting the pins back out. I also change the pins at the same time as well.

I have had two this season so far that had excessive AC head pressure even with the system turned off. This was due to a faulty expansion valve. That was the original complaint, the engine fan stays on all the time. Another way to rule out a clutch that has mechanically failed is to bring the engine RPM over 1900. After a few seconds you should hear it fade out regardless of AC head pressure or coolant temperature unless it has mechanically failed.

Just disconnect the actuator cylinder on the exhaust brake flap. The engine brake is the same as any but they just added an exhaust brake as well. It helped a little with braking but it kept things quiet! I used to see them all the time with the cylinder bypassed. Drivers want to hear them Jakes!!!!

Need to find out what blink code its logging if possible. I know its gonna be hard but when the malfunction light comes on, turn the cruise control on/off switch to off. Then push the other cruise button either up or down, does not matter. The malfunction light will blink, then pause and blink again. Count the first group of blinks and then the second group and that will be your blink code. I have had in the past an EUP, an engine position sensor and a throtle position sensor cause an intermittent skip as you have described. Im not saying thats whats wrong with yours but that the common things I have seen in my area.

If its ever had an issue with coolant in the oil or if its higher milage the cam bearings have also been found to cause low oil pressure to the top end which is what makes the Jakes work. I have encountered this on several occasions.

Ok, my first post so here goes. Its not a common problem but it has been an issue with coolant in the EECU. I thought it was limited to just the left hand redesign modules only but about two months ago I made a service call for a customer and this was his problem as well with a EECU mounted on the right side. The most common cause for the coolant leak is the Coolant level sensor. Unlug it and see if there is not coolant in the connector. It leaks internally and creates a wicking condition where the coolant runs down the inside of the wire insulation and into the module. The harness, module, and sensor will have to be changed and they should also add the anti-wicking harness in line at the coolant level sensor. It is a special harness about 12" long that will prevent this in the future in the event of a coolant level sensor failure.