Bus Conversions dot Com Bulletin Board
October 01, 2014, 11:20:27 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: If your computer is lost, damaged, or stolen, we will replace all of your E-Mags for free.
   Home   Help Forum Rules Search Calendar Login Register BCM Home Page Contact BCM  
Pages: [1]   Go Down
  Print  
Author Topic: How strong should a GM reversing solenoid be?  (Read 1813 times)
Casper4104
Jr. Member
**
Offline Offline

Posts: 80



WWW

Ignore
« on: May 07, 2006, 09:37:41 PM »

How strong should a GM reversing solenoid be?

I had the Horizon Coach guys fix some problems on my 4104 before I picked it up in March. One of the things they did was install a shiny new reversing solenoid.

I brought the bus home and have run it very little since.  The reversing solenoid has been used maybe 20 times.  Now it won't work.

The solenoid actuates, but doesn't pull hard enough to engage the gear.  With the switch thrown, I can easily overpower the solenoid and pull it back out with 2 fingers.

I had my partner hold the switch for a second and checked for 12 volts to the solenoid, and that seems Ok (12.7VDC at the solenoid lead).  So then I thought that maybe I wasn't getting the amperage that I need, so I straightlined the solenoid to the starter lug for a second and got the same result.

I called the bus dealer and talked with the wrench there (he and I really hit it off), and he told me to do the 2 little tests I just described.  I'll call him tomorrow and tell him I think it failed the tests.  He's in contact with his parts vendor about a replacement, so maybe I'll get good news tomorrow.

How strong should that rascal be?  I can pull harder with my, ummmm, nose.  That thing's the size of a soup can - it sure seems like it should be stronger than that.

Any input? Tips? Tricks?

Thanks in advance,

Casper4104
Logged

If a half a hen lays a half an egg in a half a day - how long would it take a monkey with a wooden leg to kick the seeds out of a dill pickle?
DrivingMissLazy
Hero Member
*****
Offline Offline

Posts: 2634




Ignore
« Reply #1 on: May 08, 2006, 06:48:21 AM »

Make sure you have a good solid ground connection. Maybe a hardwire back to the battery negative post?
Richard
Logged

Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body. But rather to skid in sideways, chocolate in one hand, a good Reisling in the other, body thoroughly used up, totally worn out and screaming:  WOO HOO, what a ride
Len Silva
Hero Member
*****
Offline Offline

Posts: 4086


Angle Parked in a Parallel Universe


WWW

Ignore
« Reply #2 on: May 08, 2006, 07:54:10 AM »

I don't have the book in front of me but, it seems that I recall something about the solenoid having two coils, the first one pulls it a little bit and a set of contacts inside the solenoid closes and operates the main coil. It's purpose was to limit the arc at the switch. It could that that part isn't working properly. Those old solenoids could be dissasembled and repaired. That's from memory and from my 1955 4104 manual, may not be current information.
Len Silva
Logged


Hand Made Gifts

Ignorance is only bliss to the ignorant.
Len Silva
Hero Member
*****
Offline Offline

Posts: 4086


Angle Parked in a Parallel Universe


WWW

Ignore
« Reply #3 on: May 08, 2006, 01:11:57 PM »

I went and dug up Da Book and I was almost right.
The solenoid does have two coils, one called the pulling coil and the second called the holding coil. I think these are wound together, so you would not actually see two coils but two circuits.

When the solenoid is operated, both coils are in operation. When it hits the end of it's travel, a set of contacts disconnects the pulling coil. If this contact is open, then only the holding coil would be in operation when you apply power to the solenoid.

I think you can pull the back off it and check these contacts. Probably a simple fix.

Len Silva
Logged


Hand Made Gifts

Ignorance is only bliss to the ignorant.
Casper4104
Jr. Member
**
Offline Offline

Posts: 80



WWW

Ignore
« Reply #4 on: May 08, 2006, 01:40:02 PM »

Good news.  I talked with the mech and described my symptoms and test results, and he agrees that my brand new solenoid is probably fried.  Hes getting in contact with his parts vendor about a replacement.

Well see how it goes.  Elec parts are usually warranted until you get them out of the box.

Thanks for the tips,

Casper4104
Logged

If a half a hen lays a half an egg in a half a day - how long would it take a monkey with a wooden leg to kick the seeds out of a dill pickle?
Casper4104
Jr. Member
**
Offline Offline

Posts: 80



WWW

Ignore
« Reply #5 on: May 12, 2006, 04:25:00 AM »

Good news  Smiley the shop is going to replace my bad solenoid under warranty.

Thanks for all the help with this.

Casper
Logged

If a half a hen lays a half an egg in a half a day - how long would it take a monkey with a wooden leg to kick the seeds out of a dill pickle?
FloridaCliff
Hero Member
*****
Offline Offline

Posts: 2458


"The Mighty GMC"




Ignore
« Reply #6 on: May 12, 2006, 05:02:38 AM »

Casper,

Thanks for the update.

As you know, so many times we never hear the end of the story. Sad

Cliff
Logged

1975 GMC  P8M4905A-1160    North Central Florida

"There are basically two types of people. People who accomplish things, and people who claim to have accomplished things. The first group is less crowded."
Mark Twain
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!