start solenoid won't engage

[David Anderson]

2nd time it's happened.  Drove the coach 2 hours on a short trip.  Stopped in front of my campsite to unhook the towed.  Tried to restart the bus and it would not engage the starter.  I pulled the dust cover off in the engine room and could hear the relays click (two of them) but no starter solenoid engagement.  I pushed the button about 5 or 6 times then it started.  It did this once before, same thing.  I could not duplicate it on the rest of the trip. 

Is it because of the heat?   What's up with it?

David

[Gary Hatt - Publisher BCM]

Are you sure the tranny is in Neutral and the E-Brake is set?  Those are always the first two questions.

[buswarrior]

Heavy cables have hidden corrosion, starter solenoid needs refreshed, batteries are fading...

Beat that bus into submission.

Happy coaching!
Buswarrior

[David Anderson]

Yes it was in neutral because I could hear the starter solenoids in the wiring compartment click when a start attempt from the rear was made.  After 5 or 6 button pushes I heard the solenoid on the starter engage an she fired up on the first roll of the engine like normal. 

The excessive heat may cause some not so tight wire in the circuit to make poor contact somewhere. 

[richard5933]

Could the starter solenoid itself be in need of a rebuild or replacement?

[David Anderson]

Could the starter solenoid itself be in need of a rebuild or replacement?

It may be.  That is probably the first thing to replace after cleaning all the wire connections.

[richard5933]

Is the starter solenoid on this bus the kind that can be opened up? If so, perhaps turning the disc around will help for the short term. I've read about the contact side becoming damaged from arcing as it open/closes.

[David Anderson]

Is the starter solenoid on this bus the kind that can be opened up? If so, perhaps turning the disc around will help for the short term. I've read about the contact side becoming damaged from arcing as it open/closes.

Don't know.  We just got home Friday.  It's so hot that I have little desire to get out there and work on things.  I'm picking the knowledge base here to get some pre ideas what to look for when I launch my assault  
I still haven't attacked my oil temp gauge issue.  https://www.busconversionmagazine.com/forum/index.php?topic=34215.0  It is too stinking hot outside.  100 degrees every day

[Jim Eh.]

Is the starter solenoid on this bus the kind that can be opened up? If so, perhaps turning the disc around will help for the short term. I've read about the contact side becoming damaged from arcing as it open/closes.

Although that works good for the plate but the button must also be dressed. If there is not enough left of the button to clean up, find a used solenoid/bad starter/misc spares to rob parts from. or alternatively, buy a replacement unit. Low(er) voltage is quite often a starter killer. Make sure the entire electrical starting system is up to snuff or it probably won't be the end of your issues.

[akroyaleagle]

I've seen a few of these when the solenoid is bad or getting so.
They are available at any parts store and don't cost much.
That's my bet!
Easily check by jumping across it and have someone press the start button.
You can do it yourself if you have rear start.

[Glennman]

1974 MCI MC-8. Monday before last I pulled the bus up to the house so we could do our final loading before heading to the beach 250 miles away for the week. All ready to go!!! Nope, bus wouldn't start. Pulled the starter, took it to the auto electric outfit, they installed a new solenoid for $94.00. Put it all back in (didn't actually have to pull the entire starter, but you all know how it is). We left that night at 6:00 pm, and arrived at the beech at 11:45 pm. The starter almost ruined our trip. The guy at the auto electric outfit told me that RV stands for Ruined Vacation.

Glennman

[windtrader]

The starter almost ruined our trip. The guy at the auto electric outfit told me that RV stands for Ruined Vacation.
Glennman

Isn't that the truth for all RVs belonging to families slaving away to survive and pay for some toys and holidays. Busnuts have a wide range of backgrounds and daily humdrum. You need to feel badly for those working families that break down a day out. For some busnuts here, pull out the lawn chair, chug a Bud, and take a nap - wake me when it's ready to go.
Then again, there are stories where breakdowns become the vacation with plenty of funny memories - enjoy the trip. you'll get to a destination someday.

[Glennman]

Yep, I must admit, I like working on my bus more than using it. I tell people I like going places, but I don't like arriving. For me, its all about seeing the sites and having the experiences. All my life I have always thought outside the box, making my own tool for a task, building my own house, or figuring out my own way of doing something. When I walk through a hardware store, I never ask for help, not because I am a man, but because I am trying to figure out how I can use some part or tool for something other than its intended purpose. My wife and I have looked at many RV's, and we could afford to spend 25k or so, but I need something I can gut, take a hammer to, etc. Otherwise, it would just sit in the yard all year until we go somewhere. With the bus, I always have something fun to do, including taking out the starter. It was kind of fun, thinking back. Glennman

[chessie4905]

It amazes me how many conversion owners don't  touch the starter till it let's them down. As old as most of these are, it should be one of the first items to pull and have checked/rebuilt/replaced. And
at least replace solenoid since they aren't that expensive. Also, how many starters have been ruined by low or shot batteries.

[bevans6]

Cleaning/flipping the copper disc is for when the starter solenoid works, pinion flips out, but the starter doesn't turn or sticks on.  It's the high current switch for the motor itself.  The solenoid itself has two coils, a high current pull out coil and a lower current hold out coil.  One or both of those could be intermittent/bad.  To test, take a piece of wire and jump the connection from the main live terminal (large lug with 4/0 cable) and the starter solenoid connector.  This bypasses all of the relay/switch control stuff and just turns on the starter motor directly.  If that makes the starter work every time, it's a bad ground, or a relay or a switch issue.  Putting a trouble light on the starter solenoid connection wire, disconnected from the solenoid, would be first thing I would do if the jumping thing works OK.