Shutoff Solenoid/Relay Problem
02-06-2008, 05:52 PM
#1
Registered User
Thread Starter
Join Date: Jan 2008
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Shutoff Solenoid/Relay Problem
Purchased new solenoid and relay for replacement.
However, there is no 'pull' voltage getting to either the relay and consequently to the solenoid.
The whole process seems to be timed in some way.
Any help out there on what I should be looking for?
97 Dodge RAM 2500, 12 valve Cummins, auto tranny.
However, there is no 'pull' voltage getting to either the relay and consequently to the solenoid.
The whole process seems to be timed in some way.
Any help out there on what I should be looking for?
97 Dodge RAM 2500, 12 valve Cummins, auto tranny.
02-06-2008, 06:19 PM
#3
Registered User
First check the blue wire at the driver's side battery positive for corrosion. It may be corroded under the insulation where you can't see it.
Likely this the only thing wrong, relay and solenoid are now extra parts.
If the blue wire is ok check that the small brown wire at the starter is connected and clean. This is where the power comes from to trigger the relay.
Likely this the only thing wrong, relay and solenoid are now extra parts.
If the blue wire is ok check that the small brown wire at the starter is connected and clean. This is where the power comes from to trigger the relay.
02-06-2008, 06:49 PM
#4
Registered User
Thread Starter
Join Date: Jan 2008
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Roughstock, I have no idea what happened. Was driving it normally, happily. Stopped to shop and when returned. Fuel Shutoff Solenoid would not pull. I managed to fry the solenoid, again do not know why. Was told that perhaps the pull circuit got stuck and caused the solenoid to overheat. Quien Sabe!
Bill, will check that wire at the starter motor. Have tried everything else. Thanks.
Bill, will check that wire at the starter motor. Have tried everything else. Thanks.
02-06-2008, 06:55 PM
#5
Registered User
Join Date: Mar 2006
Location: Colorado
Posts: 1,056
Likes: 0
Received 0 Likes
on
0 Posts
So your old solenoid melted? Sounds like you need starter rebuild. Just get new contacts and plunger. Larry Bs got them, i think you google "foster truck".
its easy to do. If you don't you may fry another solenoid.
Like infidel said, check the blue wire, I think mine had a fusible link attached to it if I remember correctly. it was fried too.
Hope this helps
its easy to do. If you don't you may fry another solenoid.
Like infidel said, check the blue wire, I think mine had a fusible link attached to it if I remember correctly. it was fried too.
Hope this helps
02-06-2008, 08:18 PM
#6
Registered User
The Blue wire is a fusible link (Some 98's have a fuse in the fuse box instead of this type of protection) so verify 12v on both ends or corrosion as was suggested. It could be your starter caused it to fry. Larry B's has a diode to prevent it from happening again. He has troubleshooting steps and a schematic on the site along with super heavy duty starter contacts and the blue wire (fusible link). It sounds like you need to replace your starter contacts with Larry B's.
http://www.fostertruck.com/dodge/default.htm
Here is an exerpt from Larry B's regarding the starter causing the fuel solenoid to fry:
http://www.fostertruck.com/dodge/default.htm
Here is an exerpt from Larry B's regarding the starter causing the fuel solenoid to fry:
Fuel solenoid failure almost always begins with worn starter contacts. When a starter sticks on it is caused by the worn contacts arcing and becoming welded together. When this happens the starter back-feeds 12v up through the trigger curcuit to the 70amp fuel solenoid relay. The relay then thinks it getting the power from the ignition switch so closes the relay and energizes the fuel solenoid via the "pull" coil. This is why the engine won't shut off by the key. This "pull" coil is very strong but low resistance so will overheat very quickly if allowed to stay energized. This is what causes the fuel solenoids to burn up.
So, by installing this one-way diode and preventing the starter from backfeeding the fuel solenoid curcuit we save the fuel solenoid from burning up if the starter sticks on and also allow the engine to be turned off. Again, this is the primary cause of fuel solenoid failure. A diode lets current flow one way but not the other.
So, by installing this one-way diode and preventing the starter from backfeeding the fuel solenoid curcuit we save the fuel solenoid from burning up if the starter sticks on and also allow the engine to be turned off. Again, this is the primary cause of fuel solenoid failure. A diode lets current flow one way but not the other.
Thread
Thread Starter
Forum
Replies
Last Post
barngal6
12 Valve Engine and Drivetrain
6
01-06-2009 06:30 PM