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Tim Smith
08-13-2008, 10:28 AM
So I just lately have had a problem where the new starter is not engaging. I'm pretty sure that it is being caused by the main starter/everything relay mounted on the bulkhead. This is a 74 lightweight that was running a diesel 2.5 block with a gas 2.25 head so not sure how the truck was originally set up. ;)

Looked around the catalog and haven't found anything related to this relay so instead of replacing I'm going to do a work around and start using the starter's built in relay. No big deal there...

My question is, could my the relay be the source of an electrical draw I've been experiencing? Can the relay it's self be sucking up juice?

Not a very good picture of it but you can see the relay I'm talking about just below the two aluminum boxes mounted on the bulkhead here. It's the black plastic thing with the main battery feed going to it. Click the image for a better view.

http://lh4.ggpht.com/smithco1/R-krllAgXNI/AAAAAAAABiQ/LrIr1rfuRq0/s144/IMAGE_068.jpg (http://picasaweb.google.com/smithco1/BumbaWiringAndSmoke/photo#5181720770855853266)

Curious about the forums thoughts on this.

jp-
08-13-2008, 11:50 AM
A relay is just a simple solenoid switch. Some can be wired to operate in the open or closed position. If the relay has been wired up so as to make the circuit open when the relay is closed, then yes they can draw current even when the device that they operate is not on. Relays can also stick closed.

Tim Smith
08-13-2008, 11:59 AM
Thanks JP.
I figured as much about a general relay but I'm thinking that mine is kind of broken right now. Since they operate by using a powered magnet to activate the switched circuit, I was wondering if the coil that activates the magnet could be getting power when it shouldn't be... Now that I think about it though, that would mean that the trigger wire was sending a signal when it shouldn't be so that kind of removes the relay from the problem.

I don't know. Just daydreaming I suppose.

jp-
08-13-2008, 12:12 PM
Test for 12V at the relay trigger terminal.

If you have 12V there and shouldn't, then the relay is stuck open/closed.

dunerunner
08-16-2008, 12:26 AM
Is it a 12V relay, not 24VDC?

Tim Smith
08-16-2008, 11:13 PM
Is it a 12V relay, not 24VDC?Wow, I never thought of that!

Ran great all day so I'm thinking sticky relay.