656 Glow Plug System Assistance PLEASE

[JustBoughta656]

I have a 1972 656 utility with the 282 six cylinder diesel. Everything was fine until about a year ago when the glow plug system went on the fritz. Lay of the land is, I have 12 volts to the glow plug button. When I press the button, the other side of the button then registers 12 volts. However, the Glow plug meter for some reason has quit working. My understanding of the circuit is that a hot line goes over from the button to the meter. At that point the meter works and shows that the plugs are heating and electricity goes out the second stob on the meter and down a wire and distributed evenly among the six plugs which heart the cylinders and result in a start p. However here is what is happening with mine... When I check both stobs on the glow plug meter, they are both hot with 12 volts without the glow plug meter being depressed. As previously stated the meter is non functional and the tractor wont start, presumably due to no glow plugs. When I check the glow plug junction box, there is no electricity to it if the button is on or off. I'm at a loss on this one. Suggestions? My idea is just to run a new wire to the glow plug meter and then on down to the plug junction on the side of the engine. All advice appreciated. 

[Red Flyer]

Rewire the glow plugs with a relay directly off the battery. Get a 12 volt relay and go from the battery to the relay to the glow plugs. Wire your glow plug push button to operate the relay. I did this on my 656 2 years ago, big difference, starts like a different tractor.

[snoshoe]

656 has meter in series before the switch. Your tests indicate no connection between switch and junction block

[JustBoughta656]

Snoshoe!!!!! You just helped me figure it out!!!!! I thought the juice went from the button to the meter, but the hot wire goes through the glow plug meter FIRST!!!! Ok, now I'm starting to get a little better understanding here. Lemme look at my wiring diagram again here... Btw, this all started after an incident with some mice... so the junction block may be toast.. Ok

 

[HydroTek]

Talking about the junction block on the engine head - in the center of the injectors ?

[snoshoe]

44 minutes ago, JustBoughta656 said:

Snoshoe!!!!! You just helped me figure it out!!!!! I thought the juice went from the button to the meter, but the hot wire goes through the glow plug meter FIRST!!!! Ok, now I'm starting to get a little better understanding here. Lemme look at my wiring diagram again here... Btw, this all started after an incident with some mice... so the junction block may be toast.. Ok

 

Or the wire between switch and junction block chewed in two

[acem]

Our 706 has a D282 and glow plugs.

One time he got frustrated and ran two wires. One from the battery up to the steering column and out the hole where the glow plug button and all used to be. The other wire went to the glow plugs. They just hung out there in the air. When he started the tractor he held them together with a pair of pliers, completing the circuit until it started. Crude but it worked.

I later added a ford starter solenoid and button. It was a more elegant solution.

[JustBoughta656]

Yes, I  had it taped up because it had broken loose from the engine block and had been shorting out against the fuel line. 

[JustBoughta656]

Ok, based on my new check, here is what I have figured out. The glow plug meter is hot on both sides from the battery. The switch is hot on on side, and the other side of the switch goes hot when the button is depressed. All of the hot points have 12 volts. However, when I check the connection on the junction down on the motor block, there is now juice. Solution is run a new hot wire from the button down to the junction block on the side of the engine. Which should result in juice to the plugs and effective starting. I'll keep you posted on if it works. Full disclosure, wiring is a big hole in my repair game. Red flyer suggested installing a 12 volt relay in the system. Is that necessary or am I just being crude with my electrical thinking??? and THANKS for the help. 

[snoshoe]

13 minutes ago, JustBoughta656 said:

there is now juice

If this statement is correct. You are wasting your time. If a misprint and should read no juice. Then your bypass should work.

As for the relay question: the oem system worked fine. It is when inferior parts are substituted that problems arise. Usually switches that do not handle the load.

[HydroTek]

I put one of the 1" square relays on mine years ago , because the tractor wiring was giving problems

if I had taken the time , I would have connected the gauge in the loop so I could keep a watch on glow plugs health
used 12 gauge wire (because that is what I had at the time) direct from the starter battery post
That relay is rated 40 amps , and the wire is at max load with 6 glow plugs

...but all has worked for several years -- and 20 seconds on the plugs the engine is ready to start 

"Temporary fix" at the time -- but you all know how things go on the Farm 

 

[louie figone]

23 hours ago, JustBoughta656 said:

I have a 1972 656 utility with the 282 six cylinder diesel. Everything was fine until about a year ago when the glow plug system went on the fritz. Lay of the land is, I have 12 volts to the glow plug button. When I press the button, the other side of the button then registers 12 volts. However, the Glow plug meter for some reason has quit working. My understanding of the circuit is that a hot line goes over from the button to the meter. At that point the meter works and shows that the plugs are heating and electricity goes out the second stob on the meter and down a wire and distributed evenly among the six plugs which heart the cylinders and result in a start p. However here is what is happening with mine... When I check both stobs on the glow plug meter, they are both hot with 12 volts without the glow plug meter being depressed. As previously stated the meter is non functional and the tractor wont start, presumably due to no glow plugs. When I check the glow plug junction box, there is no electricity to it if the button is on or off. I'm at a loss on this one. Suggestions? My idea is just to run a new wire to the glow plug meter and then on down to the plug junction on the side of the engine. All advice appreciated. 

 I had the same with my 282, it was the glow plug switch. Put a jumper (bypass) on the switch to test.