L210 Glow Plug Resistor

jwage

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Thanks D2Cat. That is another good option. I went out looking for it today but being that it is Sunday most places are closed. There is an electrical supply store in Lebanon, Tennessee that I think will have them. Ace Hardware might too.
 

jwage

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Dave_eng, in the picture I posted showing how the washers are stacked/positioned, do all of those need to be insulated ceramic, or just the ones that touch the mounting frame and center the bolt through the hole? Now that I am thinking through it, it seems like all the other ones would have to be metal in order for it to work.
 

imnukensc

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Don't get stuck on "ceramic washers." As Dave said in his first post in this thread, the washers just need to be nonconductive like micarta, G-10, thick plastic, etc.
 

jwage

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Ah ok I thought it had to be ceramic because it would get really hot. Thanks!


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Dave_eng

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Dave_eng, in the picture I posted showing how the washers are stacked/positioned, do all of those need to be insulated ceramic, or just the ones that touch the mounting frame and center the bolt through the hole? Now that I am thinking through it, it seems like all the other ones would have to be metal in order for it to work.
From the image you posted of the resistor itself, all I saw was electrical terminals broken off. The support or terminal of the resistor to the frame likely are OK of left alone.

Remember, the resistor end terminals need to be isolated from the frame so that the resistor is in the circuit.

If you use material that is not both an insulator and tolerant of high temp, you will have a serious short.

A plastic washer would work momentarily but would break down as the resistor heated up.

Dave M7040
 

jwage

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Thanks Dave, that's what I thought.

When I took it apart one side was ok but the other broke when trying to get the top nut and washer off in order to install new wire terminals. I ordered the parts to rebuild both sides and I will test it with an electrical meter once I put it back together to make sure it's insulated from the frame.


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100 td

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I would not recommend plastic, in time it may fail due to heat. Use fibre washers if you can't replace the ceramic.
It appears the resistor is there to create a voltage drop to limit current to the glow plugs, which appear to be in series with each other and the resistor. Not sure if anyone has done a mod on this engine and replaced the stock plugs with 12 volt ones and a small solenoid, but it's certainly one option if you run into trouble with the plugs or resistor.
EDIT: I think I need a speech to type program to speed things up!
 

100 td

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And at this stage I can't think of any other circuits that I recall seeing SERIES connected glow plugs in, but there are possibly many more in these older tractors.
 

jwage

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Hi Everyone,

I got the ceramic insulated washers in today and got the resistor coil put back together and mounted. The indicator coil in the dash glowed red hot in about 10-15 seconds, and the resistor coil glowed after about 30 seconds and then I tried to start it. It didn't seem to want to start any easier and it was blowing white smoke. How long should I wait?

I didn't pull out the glow plugs yet to check them but when I touched them from the outside, they felt warm. Could have been my mind playing tricks on me though. How can I verify the glow plugs are functioning now as a next step?

Thanks, Jon
 

Dave_eng

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You need to post some pictures of how you have the glow plug wiring done at the glow plugs themselves.

Your tractor is a bit unique with "in series," GP's compared to today's way of wiring them in parallel and this needs to be checked as a precaution.

The GP's will be branding iron hot when working correctly and just touching them and feeling warm is not helpful.

Dave M7040
 

jwage

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Good call on the pictures. That would help :)

The first time I tried it there was smoke coming from the resistor coil but I think it was just from whoever painted over the coil and dust/dirt from not being used in a long time. The second time it got red hot and no smoke came from the coil.

Edit: in the first pic next to the left glow plug you will see another broken item. I think that was the choke cable that looks broken off.




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100 td

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You may well be lacking enough fuel, or compression,try bleeding your injectors.

If you don't want to pull the plugs to check them, as the glowplugs are in series, if you have a digital volt meter you can measure the voltage drop across each plug and the resistor. You should have relatively the same voltage drop across each plug when they are powered. If you don't, one plug may have an internal short or be of a higher resistance than the other and not be functioning correctly. If you have a current clamp similar to this you can measure the circuit current, which is the same through the resistor and the plugs.
http://www.orangetractortalks.com/forums/showthread.php?t=31776
 

100 td

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Have just seen your pictures, it's difficult to see if the plugs are wired in series, (It appears they may not) the power lead into the first needs to be on a different terminal to the wire leaving to the next plug, and same at the next plug. (Unless they have been changed to different voltage plugs at some point)
 

100 td

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So the wire from the switch to the first plug should go under the top screw, and the wire leaving the second plug to ground should also be under the top screw I expect.
 

Dave_eng

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I am suspicious of the wiring connections at the glow plugs.

It is extremely important to make sure the plugs them selves are wired correctly. The indicator will get hot even if they are not wired correctly... The indicator will glow, but the plugs will not get hot enough and the tractor will blow white smoke. The white smoke is raw fuel.

There are two distinct electrical terminals on each glow plug and no two wire terminals should be at the same place on a glow plug.



Dave M7040
 

100 td

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So the wire from the switch to the first plug should go under the top screw, and the wire leaving the second plug to ground should also be under the top screw I expect.
So from Dave's pic, the 2 plugs are joined to the bottom terminals via the jumper between the 2, then as mentioned above, , power needs to be in on top connection, and ground out on top connection.
Edit: Wish I could type quicker! Yes that new pic certainly shows the incorrect wiring, and a lot of paint on everything!
 
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