1989 no start, glow plug controller

[colorado_joe]

HELP!
(Broomfield Colorado)

Made it to work this morning in Colorado, but won't re-start to go to lunch (and hopefully home in 3 more hours).
When I turn ignition to the "Wait to Start" position, the glow plug relay just does it's "hard" clicking noise immediately. This is the noise I usually get when the 8 seconds for the glow plugs to heat up is complete. So it's skipping the heating up period and not starting. The "Wait to start" light does not come on either.

I replaced glow plugs a year or so ago with motorcrafts, but didn't replace the glow plug controller. (maybe I should have...)

Can I bypass controller in the parking lot? Ex: touch a wire from a hot to the glow plugs and warm them up without using the relay? Count to 8 and take the wire off.

For right now I plugged the block heater in to see if that will help.

Thanks,
Joe

 

[maverick350]

Sounds to me like a weak plug? factory defective parts aren't un-heard of.

Mine started in 5f with just the block heater in 3 hours, but i had to put a battery charger on it to increase cranking rpm. I suspect without that it wouldn't have started.

Barring that I would try to find a way to get at the solenoid and hold open manually for your 8 seconds with a piece of wire or a screwdriver with someone else ready to crank. If it's the newer style controller the small terminal closest to the driver holds the relay in. At least that's how mine was set up.

Hopefully someone comes along with better ideas. Good luck.

 

[greenskeeper]

you can jump the relay to energize the glow plugs and then try to start it.

 

[colorado_joe]

Thanks for the feedback. I think I'll need to jump the engine mounted controller, not so much the fender mounted relay.

I check the ohms of each glow plug and they were all less than .5.
The engine does crank and try to turn over, just isn't catching.
I do have continuity between the wires at the fender mounted relay and the wires at the controller.
Batteries are good.

So I plugged in the truck for about two hours, and it did sound closer to starting now. I think my issue is still related to the glow plug system somehow.

As far as jumping the glow plug controller, I was thinking of just taking a length of wire and holding it across the double yellow wires (hot) on the controller and the green/brown wires going to the glow plugs at the end of the busbar. Perhaps I'll try for about 10 seconds, then longer if needed. I'll probably grab some nice insulated pliers to hold the wire with.

 

[colorado_joe]

Made it home! Truck started and all. All I really did was leave it plugged in for 3 hours and it worked.
So after the 3 hours of having the block heater plugged in, the controller and wait to start light began working like normal. I turned key to run position, the wait to start light turned on for the normal time, then the controller relay clicked as normal, and it fired up.
Drove home for 25 minutes, shut it off, and then tried to restart and it started like normal again.

One more thing to look into, although truck got me home once again!

 

[maverick350]

Glad to hear you made it!

I wonder if it is possible for a glow plug to be intermittent or if the the controller itself is breaking down inside?

Would be interested to hear what the fix was when you do pinpoint the issue.