Glowplug relay chatter!! At wits end!!

[blueblaze]

I have a 1985 ex-coast guard m1009, anyways, my old glow plug card took a dump and so i wired in the ground switch for the old relay. Well i wanted the automatic system back, so i went to advance auto and bought the s603 relay (same as st85 only 50 bucks cheaper). I also bought new ac60's aswell. The coast guard had removed the resistor and moved the wire to the front battery as is normal when they fail. I also bought a new cucv legacy glow plug card, helluva lot better then paying $150 and up for a used one. Anyways, i installed everything it all went flawlessly, but the relay chatters right when it ends it cycle. So i figured my batteries were on the way out as that is usually a sign of low voltage. Put in two brand new 875cca exides. Still chattered, so i rebuilt both my alternators as the red light would flash from time to time and they were taking longer to excite. The relay still chatters. I replaced both the blue wire and pink/black wire connectors as they looked really worn. It still chatters. I pulled the entire glow plug controller harness from the truck, took all the tape off cleaned it all. Cleaned all the connectors, put electrical grease in each one, retaped it all and reinstalled it. It still chatters.i also unplugged the main harness from the firewall and cleaned it aswell. I also noticed that maybe my ground was bad so i cut the black ground wire coming from the controller and grounded it to the 6 terminal ground buss underneath the left side of the dash. The relay gives about 11 volts at the pink black wire when it is cycling. Its supposed to be 12 volts. I cant figure this out. I even pulled the column down and cleaned the ignition switch, cleaned the fusebox and put all brand new fuses in. It still only gives about 11 volts. Oh and i replaced all battery terminals and the fusible link on the ignition feed wire from the battery. Am i missing something? Please help. Its really frustrating and i dont want to wreck anything by letting this go. Thank you kindly in advance for any help or advice.

 

[xenocath]

i bought same card and am having same issue it does not seem hurt anything i've had mine in for a few months now no ill effects i can see from the chatter.

 

[GFB]

I think the chatter is normal. I was under the assumption it's clicking on and off rapidly to protect the glow plugs from overvoltage.

 

[Mohawk Dave]

My card is the one that was on my OH9 when I got it in Feb '11 and 15k miles later, still chattering every once in awhile after start up for a few seconds. This is the ONLY thing on my truck that i let slide, and at this point it is b/c my 6bt is going in soon. But I am interested in knowing what it is doing when it chatters. I've read that it is cycling the GPs, but the poster did not seem certain so I was not convinced. Anybody?

-Dave

 

[blueblaze]

its like, the card isnt giving it enough voltage, who knows. its gonna wreck the relay quicker tho because its
constantly arcing when it gets to the end of the cycle. i think i might take the fusebox off and take a look. because
with the key on i checked ignition voltage at the plug connector on the firewall and it says 12.45 volts. so im losing voltage somewhere between the fusebox and controller. ill let you know what i find.

 

[mistaken1]

As I understand the circuit you should have full battery voltage at the pink/bk wire (front battery only) on the relay.

The card does not 'give' the relay voltage. All it does is ground the other side of the relay.

You should read 12.45V or whatever your front battery is at on the pink/blk wire with the key on.

What does the pink/blk wire voltage measure at the glow plug controller?

Perhaps it is a ground issue where the blue wire / card / ground is not good. Electrons move from negative to positive.

This colored diagram is courtesy of warthog (I believe, I have started putting posters names on the images they post so I can credit them when re-posting their information, this came from before that practice)

 

[frankieg]

I have the exact same chatter after I bought a controller from CUCV electronics (CUCV Legacy). I called him and he really didn't have any answer except that it won't hurt anything

 

[doghead]

Are all 8 of your GPs good and your GP relay the correct relay and good?

And, do you still have the resistior wired in with 24 volts?

Did it work with your old card?

 

[frankieg]

Glow plug relay chatter

I tested all 8 glowplugs - all good - 2 month old glow plug relay from Napa. If I put the original controller card in - it only chatters every now and then. Put the new Legacy card in and it chatters every time it ends its cycle. Also how long shoud it do the post glow? Mine will stay on for about 15 seconds after it starts. I also by-passed the resistors for the glow plugs

 

[Baradium]

I tested all 8 glowplugs - all good - 2 month old glow plug relay from Napa. If I put the original controller card in - it only chatters every now and then. Put the new Legacy card in and it chatters every time it ends its cycle. Also how long shoud it do the post glow? Mine will stay on for about 15 seconds after it starts. I also by-passed the resistors for the glow plugs

Did you try adding resistance back during your check?

I know it will make the plugs hotter, but those plugs can be finicky and it may reduce their life. Also, glow plug controllers work based on resistance and current flow. Some controllers have issue with not enough resistance just like they do with too much.

If you are talking about the relay clicking on and off about once or twice a second, that is normal. It's to help keep the glow plugs warm while you're cranking the engine and during the very initial engine warmup. You can't just leave the relay on becuase the plugs are already hot. A longer cycle would have a much higher chance of overheating the plugs.

Most diesel engines with glow plugs continue cycling the plugs after engine start. Depending on the controller, the glow plug light itself may or may not cycle. Even a modern engine such as a powerstroke or duramax will cycle the glow plugs for very short periods of time, you just won't see it. 15 seconds sounds about right for a primative system. On a modern engine it might occasionally cycle them for a few minutes into warmup, I'd have to look it up in a manual for the actual timing there. If you'd like I can time the post start glow on my 6.2L GMC plow truck when I get back to AK.

One reason you might notice a change is it might be an intentional change to the design of the controller as an update for how it handles glow plug timing after start.

If you really don't like it, put a push button switch after the key in the glow plug circuit. When you want to start hold the button down and it'll allow the relay to act normally, then you can release the button whenever you want and it will remove power from the relay.

 

[mistaken1]

Rapid relay cycling is different from 'chatter'.

Chatter is a buzzing or vibrating effect. Chatter is usually caused by low voltage.

The voltage level is such that the strength of the magnetic field developed by the coil is just about equal to the strength of the spring that counteracts the coil field and consequently the contacts vibrate between opened and closed causing arcing and damaging the contacts.

If you are experiencing chatter chances are good you have dirty connections (corroded) in the coil circuit that is causing the voltage that the coils sees to be lower than the design specification.

Rapid cycling of the relay on the other hand, seen from the beginning to the end of a cold start in a stock system is usually a sign that the glow plugs are burned out. (as opposed to rapid cycling following a normal initial glow plug heating cycle 5-10-15 seconds)

Doghead had posted something that showed the heating times for glow plugs that I cannot find but thought the AC60G needed as much as 15 seconds.
Edit: Here it is. Shows 20 seconds for maximum heat on an AC60G

http://www.steelsoldiers.com/cucv/45221-m1009-glow-plugs-24-12-volt.html#post507352

http://www.wellmanautomotive.com/pdf/go50.pdf

 

[frankieg]

I absolutely have chatter or buzzing of the GPR. I cleaned all connections and the ground buss bar where the controller card gets its ground. Measured voltages on both sides of the GPR - 12.7 volts. Load tested both battiers. If I use the CUCV electronics Legacy card - it buzzes every time. If I put the original stock one in - it works perfect 99% of the time. I guess the Legacy card is junk. I guess you get what you pay for - $79 for a Legacy, or $195 for NOS.

 

[doghead]

Who has NOS for $195?

 

[frankieg]

I saw one on Ebay a couple of days ago. Is that expensive? I don't know what they are worth - other than not to waste another $79 for one that doesn't work

 

[doghead]

"I saw it on ebay"....


If you read the ad on ebay, it says,

2910-01-2197842 Module assembly....New stock, we just had these made.
Hard to find item!!!

Above that it says NOS!

I do NOT see the OEM identifier on the card in their picture.

 

[frankieg]

You're right - I saw that it said NOS - is there anywhere a guy can actually buy a real NOS controller? I don't think the ones that are made today work as well. The Legacy does work - only to have the GPR chatter problems. I guess that I am too picky - but I am willing to pay more for something that will work like like the original

 

[doghead]

You mentioned that your original controller works 99% of the time. What do you mean exactly, by that?

Why are you replacing it?

I really suspect you have an issue that you have not diagnosed.

 

[Warthog]

I have just added some info to this thread.

Check out Post #23

http://www.steelsoldiers.com/cucv/62477-gp-module-theory-operation.html

 

[1stSarge]

We have had a few people contact us on this matter, and after going around for a long time with the engineers, we have thus far been 100% successful in eliminating this problem for customers.

If you are experiencing this, and you have done the trouble shooting and are sure everything else is working properly, I may be able to help.

This involves me replacing or modifying the controller.

Drop me a note via email, either use the email that you use for PayPal, or let me know what that email is.

My address is on the website, and is in my profile.

Drop me a note!

 

[frankieg]

You mentioned that your original controller works 99% of the time. What do you mean exactly, by that?

Why are you replacing it?

I really suspect you have an issue that you have not diagnosed.

Right now if it sits overnight - the GPR will buzz for less than 1 second when the GPR disengagaes. If I use the Legacy controller - the GPR will buzz for 2 - 3 seconds every time the GPR disengages