Resistor help

[123mack]

Before using the starting aid on my M816, I decided to inspect the system for loose connections, etc. As part of the inspection I pulled the glow plug and the element was burnt in two. Thinking it may hav been subject to excessive voltage, I checked the power at the resistor. 12v into the resistor, and 11.9 v out. Anyone ever see this happen? From my experience, when a wire type resistor goes bad, it usually fails to an open condition. What ohms should it read? Anyway I'll probably be needing a replacement.

 

[crasheej]

It will read what comes out the resistor. You will need a new glow plug. That is what will happen when it gets life on. And that will also run that one battery down. Then no start at all until you charge the battery. So you want to make sure the starting aid switch is off.

 

[123mack]

Maybe I wasn't clear. There is 12v entering the resistor. There is supposed to be 6v exiting the resistor,but instead there is 11.9v. And I do have a new glow plug.

 

[papercu]

South Alabama? I'm in South Ga and have never used the glow plug system on my M816, if it is that chilly a shot of starting fluid works great. IMO
The TM shows 6v coming out from the resistor and there is a
"COLD START RELAY – Maintains glow plug voltage by reducing the resistance in series with glow plug during cranking". Wayne

 

[123mack]

I'm about 40 miles south of Birmingham. You're probably right, I could get by with a whiff of ether. Just like for everything to work

 

[doghead]

Just to confirm, you have 11.9v at the GP, with it all connected and on?

I'll go out in a bit and measure one of mine.

 

[doghead]

I pulled the wire off the GP and turned on the switch, I had 9.5 volts.

I connected the wire back on to the GP and it measured 3 volts.

I did not measure any of the 4 connections on the 2 resistors.

 

[123mack]

I measured the voltage with the wire off. When I get home this afternoon, I'll measure it with the wire on. thanks

 

[doghead]

The circuit needs to be completed, for the resistors to function(drop the voltage).

 

[73m819]

I started the 819 the time it was down to 16, a SMALL shot of ether and started right up, I keep my batteries on a 1 amp float charger, so thay are ALWYS HOT

 

[crasheej]

I've got an old 9-2320-260-20 corrected copy dated July 1972 If I knew how to scan all the you would have how to check the cold starting system out . One of thefrist things it says is disconnect the 575 wire from the glow plug connect the multimeter, set to the 50-volt scale, between 575 wire and engine block . Turn cold start switchon. Meter should indicate 12- to 13-volts and cold start indicactor brillance should increase with plug disconnected. This iss on page 2-95. Like I said these is an old copy.Don't know what the newer one says.

 

[123mack]

That is what I did, pull the wire off the plug and connect meter between wire and block. Resistor might be good after all.

 

[jaxsof]

I have April '95 already digitized, if you want it, Ill see if I can put it in the archives

 

[crasheej]

That would help a lot of us out here in want to know land.