Voltage reducer for Glow plug?

[Michelxb]

I just try a new switch and all the circuit of glow plug is doing great.

I am just thinking of what I always read about the slow 40-50 sec before the indicator turn red, Mine was ok after only a few sec. Perhaps the voltage is still too high but I follow the shop manual and there was not any more resistance added than the 4 glow plugs and the indicator.

I also had to built all the electricity for the lights and switches.

few days ago... after many cleaning hours.

 

[nosstrannel]

Hi guys!
Great thread this. My name is Markus, Iｴm from Sweden and I have an IH McCormick B250 MY 1958. I have some problems with the glow plugs. I know the glow plugs are quite new, and the cabling is also newly made, but I was involved with the tractor after all this, so I dont know all the details.

There is a 25A fuse on the circuit and the plugs are serial connected 0,9V, the same as the above in the thread. There is also an indicator lamp that lights up the moment I press the button to switch on the plugs, but I dont know the specs of the indicator lamp.

Hereｴs the problem. I can only glow it for a couple seconds before the fuse blows. I had 1 plug out to see if it glows, and and I did a couple of fast push-dows on the switch just to see if there was any activity, and I noticed that only 1 plug (the second nearest earth, i.e the third in the serie) got somewhat warm, all the others were cold and no sign on glowing on the one I had out.

I have checked so there are no short circuit, and as far as I could measure, the one that got a little warm was 0,8 ohms and the others 0,3 ohms.
Another thing I noticed was that the ceramic insulation on the one that "worked" is damaged in that matter is had piece of it gone.

Hope you can help me sort out what the problem might be. Maybe its as simple as buying a new plug... But Iｴm courius about if its correctly made, I mean should there even be a fuse for example? And another thing that I think is strange is that if the plug is failed, then I shouldnt have connection at all through the plug?

Hope you understand what I described

Best Regards
Markus

 

[kenstrac]

Hi guys!
Great thread this. My name is Markus, Iï½´m from Sweden and I have an IH McCormick B250 MY 1958. I have some problems with the glow plugs. I know the glow plugs are quite new, and the cabling is also newly made, but I was involved with the tractor after all this, so I dont know all the details.

There is a 25A fuse on the circuit and the plugs are serial connected 0,9V, the same as the above in the thread. There is also an indicator lamp that lights up the moment I press the button to switch on the plugs, but I dont know the specs of the indicator lamp.

Hereï½´s the problem. I can only glow it for a couple seconds before the fuse blows. I had 1 plug out to see if it glows, and and I did a couple of fast push-dows on the switch just to see if there was any activity, and I noticed that only 1 plug (the second nearest earth, i.e the third in the serie) got somewhat warm, all the others were cold and no sign on glowing on the one I had out.

I have checked so there are no short circuit, and as far as I could measure, the one that got a little warm was 0,8 ohms and the others 0,3 ohms.
Another thing I noticed was that the ceramic insulation on the one that "worked" is damaged in that matter is had piece of it gone.

Hope you can help me sort out what the problem might be. Maybe its as simple as buying a new plug... But Iï½´m courius about if its correctly made, I mean should there even be a fuse for example? And another thing that I think is strange is that if the plug is failed, then I shouldnt have connection at all through the plug?

Hope you understand what I described

Best Regards
Markus

Do you have an actual bulb or is it a little hole with a nichrome wire that glows ?
Disconnect the feed wire that goes to the first glow plug in the circuit see if the bulb glows if it does the wiring is wrong.

 

[nosstrannel]

As it lights up immediately when I push the button, I supose its an ordinary bulb...
But I will try that trick nd see what happens. Thanks.

 

[Michelxb]

I just want to write some feedback about what I did on the B414.

Glow plug work fine and are fast.
In winter I use a block heater to help.
It start at once all winter long.
I love to use the tractor to "clean" all the snow for me and my friends neighbourgs.

 

[TopHound]

I know that it is some time since the last update on this thread, but I've just been sorting the same problems out on a B275 and there seems to be some confusion in some of the earlier comments.

The glowplugs are nominally rated at 0.9V but IH seems to run them slightly hotter - I've seen the normal operating voltage being between 1.0 and 1.1V. What hasn't been mentioned is that the current is typically between 45 and 48A, so each plug puts about 50W of heat into its precombustion chamber. I've also found that as the plugs age their voltage drop increases (excluding other losses like poor connections) - I've seen some dropping 1.3 to 1.4V, presumably because their resistance has increased due to reduction in cross-sectional area of the heater part of the plug.

As has been mentioned earlier, there are effectively three connections to each plug, centre thread (one side of the heater), ring contact (other side of the heater) and the outer metal body which should be insulated from the other two. One failure mode (found on my engine) was a short between these last two and, depending which plug has this type of fault can result in one heater not working through to three not working and the other burning out quickly. I would recommend checking that the heater is actually insulated from the body.

My other problem was that the indicator/balast resistor (the thing that should light up in the "pepper pot" on the dash) had burnt out... but I couldn't find a replacement. I decided to make my own using NiChrome wire as used for many heater elements. I used a 400mm length of 65/15 NiChrome (also called NiChrome C, but other types should give similar results) size 14 SWG (12 AWG or 2.0mm if you're not in England) and coiled it as in the original. I found a supplier via Ebay and, for half the cost of a glowplug, had enough wire to make 4 or 5 such heaters. The engine now starts easily and I've the old familiar glow in the dash. Just to put the power into perspective, this indicator gives off about 300W.

 

[juanbir]

Buen dia Michelxb, primero que nada te pido disculpas por escribirte en españoll, pero es mi idioma nativo y temo que si te escribo en inglés¸ te sea mas dificil entenderme.
Yo tenia el mismo problema con mi B414, los calentadores originales SI SON DE 0,9 Volt C/U al igual que el indicador. Al conectarse en serie los 5 (el indicador y los calentadores) se suman y quedan en unos 5 volt aproximadamente, previo a estos se debe colocar una resistencia que lo que hace es reducir el voltaje que reciben, es una resistencia de alambre grueso de 8 espirales. Yo pude encontar una fabricada en Brasil (Ospina codigo 011003).
Saludos y espero que esa explicacion te sirva a ti si no habias solucionado el problema o a todos aquellos que nos hemos vuelto locos para encontrar la explicacion exacta de como solucionar este problema y que no esta explicado claro en ningun lado, creo que el error se debe a que el b275 utilizaba 2 baterías de 6 volts y se utilizaba solo una de ellas para los calentadores. Saludos y suerte

 

[coondle]

The glow plugs for a range of IH tractors are wired in series meaning all plugs have to be operating to get any heat in the pre-combustion chamber and that includes the tell-rale on the dash.
The solution that has been tried and works very well is:
Remove all glow plugs and the tell tale. Be careful to keep the threaded bushes that hold the IH glow plugs into the head.
Purchase 4 either Toyota or Nissan 12 volt glow plugs. They are in comparison to the IH ones very slim. Chose a model of the same length as the IH.
Have an adaptor collar turned up in a lathe to allow the threaded bushes to hold the new heaters in the head, with the new heaters having at least the same penetration into the head as the IH glow plugs had.
I have disposed of my BTD6 now so cannot give precise details.

The glow plugs are the same across the B prefix range of IH as these tractors were made in the UK. B for Britain ( BTD 6, B275, B250 etc). The A prefix tractors were made in Australia eg A554, AWD6, etc. The WD6 was I believe made in the USA.
The A554 engine was the same specs as a BTD6 engine except the BTD6 had a downrated fuel pump for 45 engine hp the 554 had 55 ehp on 4 Cylinders.
Back to the solution.
The Japanese heaters are 10 or 11 volt rated so put 12 volts through and they give plenty of heat especially necessary in cold climates.
Rewire the heaters to Parallel and hey presto even if a heater unit fails the other 3 will work fine and your tractor still start. A competent fitter and turner (machinist) can fabricate the necessary adaptors for the project.

IH designations explain quit a lot about the tractor
eg first there was the T6 a petrol (gas) kero tracked tractor size 6, then came the TD6, same size tractor but tracked diesel and the BTD6 the same size tracked diesel made in Britain. The TD6 had a petrol start changed to diesel whereas the BTD6 had glow plugs with the same Ricardo indirect diesel injection system into the pre-combustion chamber as the TD6
W6 , petrol kero wheeled tractor, size 6; the WD 6, wheeled diesel; AWD6, you guessed it same wheeled diesel made in Australia; the SAWD6 an AWD6 super sized ie more power; SAIWD6, the industrial version of the SAWD6, having heavier front axle, 20 inch truck style wheels, a heavier set of rear wheel weights, an upgraded crankshaft driven hydraulic pump and possibly a front end loader. An O6 was the W6 type tractor of narrow gauge for Orchard work.
Makes sense does it not?

 

[juanbir]

Hola Coondle, muchas gracias por la explicación, estuve por cambiar las bujias de 0.9 volt por las de 11 volt rosca M18 x 1,5 que se adaptan perfectamente para este motor, pero como tenía bujias de repuesto y a mi me gusta mantener los vehiculos originales me arriezgue a dejar el sistema tal cual fue diseñado de origen y funciona perfectamente bien. El B414 es fabuloso, con el puedo hacer muchos trabajos que con mi 8N no podía.

 

[omniwatch]

The glow plugs on a B414 are indeed 0.9V and they work all in series and in series with the indicator that is the voltage reducer. The glow plug does not connect to the boddy as in conventional glow plugs but has an inner and outer ring on what looks like one connector.
I,ve modified mine to work of new 11 V glow plugs. I made a bolt like plug that screws into the original hole in the cylinder head. Then I drilled a 7.5 mm (new glow plug thread size 10 mm) hole through the middle and tapped it with the same pitch as newly bought glow plugs (11V plugs). I needed to use a washer so the new plug tips are the same length as the old ones. I then connected them all in parallel through new switch directly from the battery to the plugs. It works like a dream. Count between 12 and 20 sec depending on temperature befor pushing the starter.