Question about M1009 relay repeat activation

[rhinob]

Greetings CUCV owners,

So when I start my M1009, there is a relay that clunks on when the key is first twisted. The voltage drops and the glow plugs do their magic. I start the truck after the wait light goes out and, while running, there is another clunk, then off, then clunk, then off, then clunk, then off. While this is happening, the charge needle drops indicating a load. If I blip the throttle, the belts squeal (unless over tightened, which I won't do).

Can anyone tell me if this is normal? It happens with both my normal GP controller and my backup controller. The GP replay has been replaced (it did fail about a week ago).

Thanks....

 

[gungearz]

Can you be a little more specific on where the clunking is coming from...?

 

[doghead]

Normal, yes. It sounds like you are describing/hearing the GP relay cycle in the "after glow" cycle. it should stop after about 30 seconds.

 

[rhinob]

Excellent, thank you. I suspected this was normal since by GP controllers behaved exactly the same way, cycling the relay, etc.... Makes sense. I just have to wait for it to quit cycling to avoid a belt squeal while it's engaged.

 

[Barrman]

Do you still have the 24 to 12 volt resistor on the firewall behind the engine on the firewall hooked up?

If you don't, I would suggest you do a load test on the front battery because the glow plug relay chattering like you describe could be caused by not enough umph at the end of the glow time. Try switching front and rear batteries and see if it still happens. Your alternator belt making noise at start up also supports the battery is getting really discharged.

All stock set up with the resistor and I don't know because both of my M1009's don't have the resistor.

 

[rhinob]

I wouldn't call the relay clicking a 'chattering' like low voltage. Seems like a deliberate re-engagement of the GP system as described as an 'after-glow' by Doghead above. The only time the belt squeals is when the voltage needle shows GP engagement. After this process is complete, not belt squeal (do to load).

PS - I'm pretty sure my resistor is disconnected as the wires coming out are clipped. Something that should be restored? I found this interesting as the previous owner is not a mechanic and he bought it directly from the military in the 90's.

 

[tequilaiam]

Does your sound a lot like a 60hz hum of a flourecent light but louder? Mine does and it drives me crazy. It sounds like that relay is taking a beating.

I've been wondering if a solid state relay would work better.

 

[Whitey]

Rhinob,
The "clunk" is normal and I agree with Doghead. I've been more in the Baltimore are recently, but could stop by Urbana sometime and take a look as I'm in Frederick about once a week. My glowplug resistor is hooked up and the vehicle is stock except for the Doghead relay. However, my father's 1009 has the resistor bypassed and the glowplugs upgaded by the military. I've looked at other's setups at different rallies and it seems its recommended to bypass the resistor so you don't have a cascading glowplug failure.

On a side note: I know you like German machinery, one of my club's members just picked up a Unimog 1300 from customs at the port of Baltimore. He's very happy with the rig. I'll see about getting some pictures.

Take care!

-Whitey

 

[Barrman]

I guess I didn't phrase my post above very well.

Yes, as mentioned several times in this thread and in many other threads. The relay does clunk on and off.

While trying to get RED going with Colton, I just threw a pair of non matched batteries we had sitting around in there to try and make it turn over. The front battery was a 5 year old 400 amp small thing and the back battery was a group 31 1000 CCA battery that is less than a year old. The truck started great.

Then we hooked up the alternators and got them working. Then we installed a glow plug relay so we wouldn't have to keep hot wiring them. The resistor is missing from the truck, so just the front battery was doing glow plug duty. At the end of the glow plug time, the relay would turn off and on repeatedly with very loud noises and eventually turn off. The truck started right though. I didn't like the noise and swapped batteries. It hasn't happened since.

That is where I got the idea a bad or low battery could be the problem if somebody is just using the front battery for the glow plugs. Since it has been written many times and the manual makes a point of saying to load check the batteries before doing any electrical diagnosis. That would still be a good place to start.

 

[MarcusOReallyus]

Does your sound a lot like a 60hz hum of a flourecent light but louder? Mine does and it drives me crazy. It sounds like that relay is taking a beating..

You need to find out what's going on there. That does not sound like A Good Thing.

 

[scottladdy]

Greetings CUCV owners,

So when I start my M1009, there is a relay that clunks on when the key is first twisted. The voltage drops and the glow plugs do their magic. I start the truck after the wait light goes out and, while running, there is another clunk, then off, then clunk, then off, then clunk, then off. While this is happening, the charge needle drops indicating a load. If I blip the throttle, the belts squeal (unless over tightened, which I won't do).

Can anyone tell me if this is normal? It happens with both my normal GP controller and my backup controller. The GP replay has been replaced (it did fail about a week ago).

Thanks....

Check this out: CUCV Glow Plug System Video - YouTube
AntennaClimber did a great job on that video.

And my , if your belts are squealing, they are either worn out or too loose. The TM calls for 67 lbs. of tension on the belts after break in stretch. Do not rely on your calibrated thumb to determine belt tension. Check this out: Dayco Krikit Tension Gauge - YouTube

About $10 at RockAuto.

 

[rhinob]

No, mine doesn't sound like a fluorescent. It's just a relay clunk that repeats for about 30 seconds or so.

 

[MakersTeleMark]

Does your sound a lot like a 60hz hum of a flourecent light but louder? Mine does and it drives me crazy. It sounds like that relay is taking a beating.

I've been wondering if a solid state relay would work better.

That's the classic sound of a nearly dead battery.

 

[tequilaiam]

That's the classic sound of a nearly dead battery.

You mean like when you're trying to start it and it's just the starter solenoid engaging/disengaging really fast?

That's not what I'm talking about. My truck starts just fine. However, maybe 10 seconds after the "wait" light turns off I hear that buzzing sound for a few seconds. The sound doesn't last as long when starting a warmed engine...maybe a half second. When it's a cold start it lasts 2 or 3 seconds.

It could be the GP relay fluttering as it gets it's power turned off by the GP controller.

I haven't bothered tracking it down because it doesn't seem to matter. It's been doing it for a year and a half and the thing still starts just fine.

 

[richingalveston]

it sounds like your glow plug temp sensor is giving bad readings to your glow plug controler card. replace the temp sensor and see if it continues.

 

[doghead]

Or, just follow the easy to follow troubleshooting in the -20.

You can test everything except the controller card.

 

[MarcusOReallyus]

Or, just follow the easy to follow troubleshooting in the -20.

Where's the fun in that?


Just guessing and swapping parts is so much more fun!


And expensive!

 

[richingalveston]

at least with the swap out way you end up with lots of spares? lol

 

[tankie88]

I had relay chatter.So after reading a few related posts i changed the relay,temp sensor,rebuilt the L/H alt,full set of new Bosch glowplugs and swopped batt positions.The chatter is still there but not as bad.Pulled the glowplug card (it looks ok) sprayed in some WD40.Still a bit of chatter.Measured voltages on the relay when in operation(all ok).Measured charging voltages (all ok) and batt voltages before starting(all ok).Went to start this morn ..wait light came on,relay went clunk but never went off.Tryed it a second time(same thing).Tryed it a 3rd time it went off and started.It also cycled properly.Sometimes while driving it will cycle again and the belt starts screeching.Anyone a clue?.