Marky's Conversion!

[EastCoastCB]

Originally Posted by MarkyDee

Sorry, no pics, but I have all the chair rails off now. Whew. 150 or so rivets to air chisel off, down at my shins. My shins have marks where the rivet heads hit them while flying around....


Thanks for the advice for the air hammer and grinding down one of my chisels.

I've got a buddy who may have a couple NF parts buses. PM me if you want his info.

[MarkyDee]

Originally Posted by MarkyDee

Well, thank God for breakers....


The crisis of a broken PLC has been avoided - it was just a tripped breaker.


Whew....

Well, that breaker "tripped" again, but this time it didn't show "tripped". It took me removing the breaker from the panel, checking continuity, and putting it back in for it to contact again.


I'm now on the lookout for new breakers....

[TEAMROSARIO]

Originally Posted by EastCoastCB

I've got a buddy who may have a couple NF parts buses. PM me if you want his info.

Im the buddy 👋 lol.. I have 14 new flyers 30 and 35 footer low floor transit coaches that we are in the process stripping and getting ready to scrap. They range from 1997-2001. The 4 30ftrs have 466e’s and the 35s all have dd series 50 engines. I dont know how much is compatible with the high floor coaches. But i would be more than glad to check and help with any parts you might need. Pm me if interested.

[TEAMROSARIO]

Originally Posted by MarkyDee

Well, that breaker "tripped" again, but this time it didn't show "tripped". It took me removing the breaker from the panel, checking continuity, and putting it back in for it to contact again.


I'm now on the lookout for new breakers....

I have plenty of these 😁

[MarkyDee]

Originally Posted by TEAMROSARIO

Im the buddy 👋 lol.. I have 14 new flyers 30 and 35 footer low floor transit coaches that we are in the process stripping and getting ready to scrap. They range from 1997-2001. The 4 30ftrs have 466e’s and the 35s all have dd series 50 engines. I dont know how much is compatible with the high floor coaches. But i would be more than glad to check and help with any parts you might need. Pm me if interested.

Ooo, I'm giddy with excitement....

[MarkyDee]

Wow, been awhile....


Interesting problem. I tried to start the engine with batteries that were too weak. The PLC that runs everything dropped out before the starter did. Before I could get to the back of the bus and flip the main breaker the starter stopped turning over the engine and "dropped out" - sounding like a freewheeling motor when it "disengaged."


Now, when I reset the main breaker, that freewheeling motor sound starts. I thought it might be that the solenoid is still engaged, but even after throwing the breaker that I think was just for the starter, that freewheeling motor sound just continues.


Any idea what it might be, and how I can "reset" it so that I can re-engage the main breaker without the freewheeling motor draining the batteries?


Thanks!

[BlackJohn]

Sounds like time to recharge your batteries before anything else.

Disconnect them and charge individually. When both are ready then reconnect and try to start.


John

[MarkyDee]

Originally Posted by BlackJohn

Sounds like time to recharge your batteries before anything else.

Disconnect them and charge individually. When both are ready then reconnect and try to start.


John

I'm doing just that (except the charge individually part). I'm still concerned about the freewheeling motor sound. I'm not sure what will happen once the batteries are fully charged should the starter actually engage before the PLC is ready for it....


Guess I'll find out....

[BlackJohn]

Charging both at the same time will not give you a good indication of battery condition Marky. One could be much weaker than the other but you won't know unless you separate them to charge. I know, takes more time etc but tells a tale.
I think when both come up the PLC will recognize that and reset things, hopefully disconnecting the power to that starter motor. It might be weak enough right now that that coil is underpowered and won't de-energize.


I was just reading above about the breaker issue. That could be doing this. Can you change it or test it? Sounds like it isn't disconnecting the circuit. Pull the wire off the starter and check for voltage if possible.

Good luck,


John

[MarkyDee]

Sorry for the dead-air. Christmas and all....


Anyway, about a week ago I pulled the charger off the batteries and the batteries off the bus (I had the charger on all Christmas and New Year's), let them sit for a few hours, and tested them with a multimeter. One read 13.7V, the other 11.2V. Yup, dead cell in one of the batteries. I was hoping to go one more season with the batteries before having to replace them....



So I went to Interstate Batteries and bought two 8D-MHD batteries:

https://www.interstatebatteries.com/products/8d-mhd


Turns out the batteries I took off the bus were screw posts, and the new batteries are top posts. So, I bought two sets of brass top-to-screw-post adapters:
https://www.amazon.com/dp/B0787NPBFN..._t1_B07DWZNVH1


Hopefully I'll get everything sorted tonight or tomorrow, as we have snow forecasted this weekend.


And hopefully the brass converters will handle the starting current....

[MarkyDee]

Ok, I got new batteries installed. Threw the main breaker and the freewheeling sound started up just like before. I just turned everything off and went inside (I didn't try starting the bus).


So, now I'm really concerned. Did I break the starter?

[BlackJohn]

That sounds like welded contacts in the starter. With age the contact area lessens and they just weld from the heat and can't disconnect.


If you can safely crawl under with a bfh and give the starter a few whacks. Might free those contacts but likely will need removal.


John

[MarkyDee]

Originally Posted by BlackJohn

That sounds like welded contacts in the starter. With age the contact area lessens and they just weld from the heat and can't disconnect.

If you can safely crawl under with a bfh and give the starter a few whacks. Might free those contacts but likely will need removal.

John

I've been researching this for over two weeks now. Nowhere on the internet is the "contacts are welded" answer. This answer makes perfect sense to me.


Thank you so very much! I don't know if I can get under it, but I have a huge davenport in the floor above the engine, so I'll see if I can get to it that way.

[MarkyDee]

Ok, I now have a very sad face.





And of course I wanted to say some expletives.





So, after purchasing a furnace key and a 5/16" square, 2" bar stock, I finally got the floor hatch up. The engine is literally directly below the hatch. The starter is underneath a mess of wires, tubes, and the air intake (a honkin' 4" stainless? steel tube). I can't get to it from above. I can't get to the starter from the side as its all steel framing. I can't get to the starter from below 'cause I can't get under the bus.


I'm soooo really stuck now. Looks like its a tow unless the community here has some sort of incredible idea. I'm fresh out.

[joeblack5]

The freewheeling you describe is the starter motor turning but not turning over the engine.?
With most starters you have a large relay that delivers current to the starter solenoid. that current also gets the starter to run but it has no power at that moment. At the same second the starter starts spinning the solenoid would engage and push the now rotating starter gear in the flywheel. As soon as the starter gear is engaged with the flywheel gear it closes the main contact that allows full battery current and torque to turn the engine over.

So if you hear only freewheeling and no click when you connect the battery I would look for the smaller wire out of the starter motor and disconnect that.
Does the motor still freewheel.?
If not the likely your solenoid is stuck and does not engage the starter motor. As john mentioned a whack with a hammer can dislodge it. ( temp solution) At the same time you need to see why you have voltage on the smaller wire in the first place. Potential the starter relay is stuck in on position.
Assume you have a 24 v system.

Good luck Johan

[MarkyDee]

From what I understand, the solenoid that is supposed to slide the starter worm gear forward is the agent that then provides power to the actual starter motor once the worm gear has fully slid forward and engaged the engine's flywheel.



Whenever I engage the main breaker (to provide electricity to the whole system), I hear a "freewheeling motor" sound. The theory is that the contactor on the worm gear has welded to the contacts, providing power to the starter motor even though the worm gear hasn't slid forward, so the starter motor is spinning w/o being in contact with the flywheel.


All that to say that I have to physically get to the starter before I can do anything to it. Doesn't look like I can even get to the starter to even begin verifying that theory is actuality.


I'll post pics tomorrow once I get better shots from above. The pics I have are very grainy because I had very little light for the camera to work with.

[BlackJohn]

Originally Posted by MarkyDee

From what I understand, the solenoid that is supposed to slide the starter worm gear forward is the agent that then provides power to the actual starter motor once the worm gear has fully slid forward and engaged the engine's flywheel.



Whenever I engage the main breaker (to provide electricity to the whole system), I hear a "freewheeling motor" sound. The theory is that the contactor on the worm gear has welded to the contacts, providing power to the starter motor even though the worm gear hasn't slid forward, so the starter motor is spinning w/o being in contact with the flywheel.


All that to say that I have to physically get to the starter before I can do anything to it. Doesn't look like I can even get to the starter to even begin verifying that theory is actuality.


I'll post pics tomorrow once I get better shots from above. The pics I have are very grainy because I had very little light for the camera to work with.

Marky your thinking above is correct and well written.



Throwing the main breaker starts the starter motor running correct?



No need to even use the key or start switch correct?


You can remove the starter relay and see what happens then. I think nothing will change doing this so verify with a similar relay in that one's place. Without the relay in there no power gets to the starter solenoid period.


That takes us then to the starter solenoid itself, which should test for no power on it without the starter relay in place. A definite physical impossibility.


So the starter motor is getting full current amps from the batteries only because the internal contacts are already made without any assistance from the starter solenoid itself, powered up or not.


You have to get that bus up and get under it. Not an easy job without a wrecker lifting the backup and lots of hardwood blocking, front wheels chocked really well to old back that much weight.
If the wrecker can't get at for a lift he will have to move it to where he can safely do so.
The bus has to go up high because you won't handle the starter without some mechanical jacking to lower it if need be.

In any case you have to first get the solenoid off of it and see what is happening.

Disconnecting the small wire on that will answer if the main contactor is kaputski. The motor should stop running on upon disconnecting that wire.



I see no other way unless you tow it in for service if you aren't up to it for whatever reason.
The starter will be a struggle due to its size and weight. You only get one chance so do not let it come down on you if it has to come out.
Best of luck brother.


John

[MarkyDee]

Yea, I came to the same conclusion - I'm going to have to jack the bus. Getting a wrecker behind the bus will be a real trick (I don't think I have the room even if I could get a wrecker behind it because my detached garage is about 20' behind the bus). I think I'm going to have to jack the bus w/o the use of a wrecker. I've got one 20-ton jack that can be air powered. I had plans to buy another, but hadn't yet. I was also thinking of using my AC-powered air compressor to feed air into the bus to get the bags inflated to give me more ground clearance.



Towing the bus out may be nigh impossible. I live on a narrow road with a telco box on the other side of the road from my driveway, a power pole on one side of the driveway (I've already hung my bus up on it...), and front yard and mailboxes on the other side of the driveway. Its tight even to get the bus out under its own power, so getting it out with a large-ish / long-ish tow truck is going to cost some $$$ (or be impossible).


So I really don't see any other option than to jack and replace. The whole operation is going to be high-risk because I've never jacked something this big before. I've also never cribbed before. It'll definitely be interesting....

[joeblack5]

Yes there are several starter motor designs. You will get familiar with them quickly. If indeed the main contact is welded then and the full battery voltage is on the starter then that will destroy in short order. The starter motor is a series design and without load it will get into a run away mode. If it is designed, as mine is, that the solenoid current is used to already bring the starter motor in motion as to improve the meshing of the gears then there is less chance on destruction. Just look at the gauge of the wires coming from the starter motor can tell you what design it is.
Good luck.
J

[MarkyDee]

Thank you, JoeBlack!


I've been spending time w/ YouTube vids of jacking big rigs, changing tires, etc. I've got a good idea about how to do this now. The fun part will be getting my bottle jacks under the bus and positioned correctly under the suspension. I've got clear access for everything else (chocking, etc.).


Once I have the bus jacked I'll have a better idea about getting to the starter.


BTW, the starter is an MT42 style. The Delco Remy part has been obsoleted three times already, but I found the latest part number that should fit. The whole starter assembly is around 58lbs. and it looks like I can get a whole new one for about $300, so that's probably what I will do. However, I'll cross that bridge when I get across all the others (i.e. jacking the bus, getting to and removing the starter, etc., etc.).


If anyone else has any recommendations, history, funny stories, etc., to add, please chime in!


Thank you all!