Wirlybird

I'll have to ask my friend about it. I'll look for those plastic lines, when it warms up a bit, but I don't recall seeing them.

My friend said the E6901 was the engine. It is on a plaque on the hood.

Actually the starter was redone about a year ago. that's why it was a little disappointing to find the loose connection. This truck is an old oil field winch truck so it sees pretty harsh conditions! I am sure it shakes everything loose. Parts are ordered for the fuel supply pump and then we can get it started again. She always drains off the fuel when sitting for periods.

Ok Guy's, thank you for all the ideas and info. Problem solved, at least for now. This AM, 17 degrees out, I removed the strap between the left solenoid post and the starter post. Found the nut on the starter post to be a bit loose as in not tight enough. that was a good sign! Once I had the strap off I found the arcing/pitting on the underside of the strap where it goes onto the starter body post. Another good sign. Tested the solenoid and constantly got power to the left post when turning the key. Good sign. Jumped the starter between right post and start post. Starter spun good. Cleaned everything up and after several trips inside to thaw out I got it all back together. Cranks right up and engaged and cranked strong. NOW, I have to replace two little plastic pieces and springs in the fuel supply pump and we'll see if it will start.

I had my meter on 2k setting which gives a tone as I couldn't see the meter while hanging over the fender to get to the terminals! Also I was first trying to see if I had a dead short in the starter motor.

Ok, to clarify, I can take the plate with the terminals on it off the back of the solenoid ok? Just concerned it will come apart and have to pull the starter. Hoping that it is bad contacts and I can replace without pulling the starter.

Yes, going to finish removing the strap and small wires to test and see if I can determine why I get continuity from the left post to ground with batteries unhooked.

Thanks, I am hoping that the solenoid shows as grounding from the post with he yellow and I can take the rear plate off. My friend said he uses a swivel on the engine side and it is turn a tiny bit, remove and reset and do it again. He's had it out a few times. At firs we would get a "click" when trying to start, like the solenoid engaging but not turning the starter. A little rapping on the start and it would go. the last few times though we got that arcing and I didn't see anything obvious on the outside so we gave up for the day. Going to be a cold on today so don't know how much we'll get done.

Need to get the starter (40MT starter) out on this Mack and my friend says that last time is was a major undertaking. Said the bold on the engine side was extremely hard to get on. Reason to take it out is I think we have a bad solenoid. We get an arc at the back of the solenoid when turning the key. The arcing is in the area of the red arrow. I tested for continuity to ground at the terminal by the red arrow that goes into the starter and got it, and also tested at the yellow arrow and the same which I expected since they are connected. I will remove the strap between those two terminals tomorrow to see if continuity is at the terminal on the start or on the solenoid. It seems I need to remove the starter to remove the whole solenoid. I am wondering if the plate on the rear of the solenoid that has the terminals can be removed without part flying everywhere! Thanks for any suggestion, tips or advice.

I think you are right. Busbar or Bus Bar is how I find it and it seems that the specific use would be as a "power" supply or distribution point where one power line in and many possible lines out. Terminal block or junction block would be a series of individual/independent "terminals". I think on the Mack the terminal/junction block is used as a point where the fender wiring can easily be disconnected from the main harness. In this case it enables you to undo the main harness connection to the headlight, blinker and parking light for the fender and then be able to remove the whole fender and its wiring as one unit. I've always used the term Busbar in a generic way to mean a strip of terminals or connection points.

You are correct!! My oversight!

The "buss bar" is just the terminal block on the inner fenderwell located near the radiator.

No kidding! That buss bar was still a pain to get to. Got the new adjusters into the buckets and new headlights in on both sides.

Problem solved! Ground from the passenger light socket went to the bus bar by the radiator but the ground going from there to the harness was bad. Replaced and working fine now. Thank you for the suggestions.

The passenger side was replaced and could be one of the aftermarket mounts but looks like a newer Mack replacement. Will be checking grounds