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Glow Plug problem

Discussion in 'Case / Farmall - International Harvester' started by Dareng, Sep 3, 2011.

  1. Dareng

    Dareng Member

    Jul 14, 2011
    Hey Everyone,

    Thought I would post this as I'm driving myself crazy trying to figure out what the problem is. And my luck its going to be something so simple that I'll be kicking myself when I hear it.

    I have an IH 434, and when I turn the ignition to pre-start, BOTH the "wait" (red light) and the "ready" light (green) turn on. Now, I can understand this happening if the engine has been running and the block is hot, but its doing this at cold start.

    My concern is that the warmer plugs aren't coming on and I'm starting the engine on cold cylinders. Is this bad for the engine? And does anyone have any suggestions on how I can trouble shoot this problem?

  2. ErnieS

    ErnieS Country Biker

    Jun 1, 2011
    If it starts fairly quickly you're fine. Mine starts on about the third revolution without waiting a lick.
    Try it on a cool morning and see what the lights do.

  3. Dareng

    Dareng Member

    Jul 14, 2011
    I have, it has been doing this since winter. During the summer months, it will start after the third or fourth crank, but in the winter it's all I can do to get it started. Could this be a problems with the glow plugs then selves or could this be a problem with the actual ignition switch itself
  4. ErnieS

    ErnieS Country Biker

    Jun 1, 2011
    Living here on the Gulf Coast, I haven't had any cold mornings since I bought the tractor in May. 65F is about the coolest I've seen.
    The green and red lights at the same time, to me, indicate a sensor problem, but I really don't know. Someone familiar with your tractor should be along soon.
  5. cyrush

    cyrush Registered User

    Apr 20, 2010
    See att 434 electrics for diesel engine.

    As built in u/k the glow plugs are fed through a dashboard glow resistor from the ign switch they do not use a relay / controller that controls lights, so the lights you talk of are something fitted in the aftermarket.

    As a test you could connect a digital multimeter to the glow plug for no1 cyl (furthest from ign switch) and seewhat it shows ???

    Turn on ign key to second position where charge warning light glows. Put stop control in run position and set throttle about 1/2 open.
    Turn key to first spring loaded position and hold there until indicator resistor on dashboard glows red. Then turn key to second spring loaded position to crank engine, release key from both spring loaded positions when engine starts. Do not crank more than 30 sec's if engine fails to start.

    Attached Files:

    Last edited: Sep 4, 2011
  6. Dareng

    Dareng Member

    Jul 14, 2011
    Thank you all for your help on this. But I'm still confused by the "glow Plug Resistor.


    Above is the dash of the tractor with the 2 lights I'm speaking of about the throttle, did these come original or have these been added in afterwards
    Last edited: Sep 4, 2011
  7. Dareng

    Dareng Member

    Jul 14, 2011
    Hi Everyone,

    Sorry, I'm doing some further research on this and now know that the silver mesh piece to the right of the steering wheel is the resistor lamp. Now, this brings me to my next question.

    At one point, the 2 lights at the top of the dash worked, where the red would light before the green, guessing indicating the engine was ready to fire. As long as I have had this tractor, the glow plug resistor has NEVER lit up. Does this mean either that someone has rerun the wiring to these lamps or does this mean that the resistor has burned out.

    Which brings me to my next question...if the resistor lamp is burned out, does this mean that the glow plugs are not working at all?

    As you can probably tell, I'm very confused at this whole subject, so anyone who can offer a guiding light on this would e greatly appreciated and any suggestions are welcomed.
  8. cyrush

    cyrush Registered User

    Apr 20, 2010
    The glowplug resistor is inside the silver pepper pot you can see just below the throttle.

    If resistor has never glowed red then it is probably burnt out and glow plugs are not working, or it could be one or more failed glow plugs so circuit is incomplete, hence pepperpot indicator is not energised.?? As you would see from the circuit diagram the components are in series so any 1 failing will stop all of them working.

    You should be able to test out voltage using a digital test meter, check for voltage when you think circuit is energised and with every thing turned off, you can do continuity (Resistance) check on pepperpot indicator and glow plugs.

    If red & Green lights are fitted to the circuit then it is aftermarket fitment and would appear to be working through a relay or small control box, have you tried tracing the wiring to see what you find ????
  9. cyrush

    cyrush Registered User

    Apr 20, 2010
    Lights on dashboard:-

    see wiring diagram

    No 81 charge warning light, (I refer to in starting instruction)

    No 82 engine low oil pressure warning,

    No 83 speed amplifier (transmission attachment, if fitted )??? *********

    No 84 illumination light for dashboard , clear, in red housing to upper l/hand of photo.

    ****** your tractor does not have this attachment !! , no control lever on dashboard, located to left of steering wheel.
    Last edited: Sep 5, 2011
  10. Dareng

    Dareng Member

    Jul 14, 2011
    Thank you so much all of you for your help with this problem.

    Is anyone in possession of a service manual with the glow plug location on the block? I would like to try and have these tested but I'm not familiar with the location or even the look of the plugs.

    Thank you all again.
  11. cyrush

    cyrush Registered User

    Apr 20, 2010
    The red light is charge (Generator )light.

    The green is engine oil pressure warning

    SEE att

    Found 3 pages from B-414 ops manual about the plugs and includes a picture. They are fitted on l/hand side of engine just below the injectors. (Service manual has no info on these !!!!)

    Remove wires from plugs noting position of washers and wether they are metal or insulating washers, at bottom of stud is a small hexagon fitting, use a ring spanner or deep socket to unscrew glow plug from head.

    Text edited and erroneous information removed @ 8-00 U/K time !!!

    Attached Files:

    Last edited: Sep 6, 2011
  12. cyrush

    cyrush Registered User

    Apr 20, 2010
    Did you fix the ignition switch issue ???
  13. Dareng

    Dareng Member

    Jul 14, 2011
    Thank you very much for the manual pages :)

    Cyrush, no unfortunately I haven't. I have been trying to find one. One international dealership I called quoted be $149 for the ignition. Does that sound like a normal price for that piece? I would hate to spend that money on it and then to find out that I overpaid :)
  14. cyrush

    cyrush Registered User

    Apr 20, 2010
    Re cost of switch, does seem high ,

    Look here


    434diesel, group 3-13 instruments, item 11, unfortunately not priced, so you need to give them a call.
  15. cyrush

    cyrush Registered User

    Apr 20, 2010
    Re ign switch i made enquiry of aU/K Case IH dealer, "Startin Tractors" here's what they say !!!


    Hi John.

    Thanks very much for your email.
    3048227R92 now changes part number to 3127632R91 and is priced at £50.00.
    Transport to USA would be £8.50

    If you need any further information please let me know.

    Best Regards,
    James Rogers.
    Startin Tractors Ltd.
    Tel: +44 (0) 1827 880088
    Fax: +44 (0) 1827 880574
    Web: Startin Tractors
    Email: james@startintractors.co.uk

    From: Richard Goodwin
    Sent: 07 September 2011 22:41
    To: Parts
    Subject: Fwd: 434 Parts

    Begin forwarded message:

    From: "darbyfarmall@aol.com" <darbyfarmall@aol.com>
    Date: 7 September 2011 21:49:02 GMT+01:00
    To: Sales <sales@startintractors.co.uk>
    Subject: 434 Parts


    For IH 434 tractor (Diesel) i need to know price and availability of the ignition switch 3048 227 R92 (from CNH parts look up pages)

    Could you also advise if possible ?? shipping costs to USA / Canada ??

    Thanks. John Darby.
    Scanned by MailDefender - managed email security from intY - intY | Enterprise Cloud Computing Solutions


    Did acurrency conversion for you

    £50 = $78.9282, + £8.50 = $13.4136

    About 1/2 price of your USA dealer ???

    Have put in dealer details above, they accept all major credit cards.

    Hope this helps you.!!!
    Last edited: Sep 13, 2011
  16. Brakeman

    Brakeman New Member

    Sep 17, 2011
    Hey Dareng just wondering how the glow plug issue was going. My Dad showed me that if you grounded the solid wire between the glow plugs starting at the front No1 and work your way back is a quick way to find the bad plug.
    Or in case of an emergency it is one way to at least getting some of the plugs to heat.
  17. cyrush

    cyrush Registered User

    Apr 20, 2010
    Be careful doing this because increased voltage to say 3 plugs could burn then out !!!

    The resistor (in pepper pot on dash) is 8volts, each plug in turn is only 1.2volts = 12.8volts, bypassing 2 plugs will cause others to burn out !!!
  18. colestation

    colestation New Member

    Apr 4, 2016
    Just found this post when trying to sort out starting problem on a 434. The ignition switch has anti- clockwise and clockwise positions. All works on clockwise actions as per your description. What is the function of the anticlockwise positions.
  19. pogobill

    pogobill Registered User Staff Member

    Jan 31, 2012
    Not sure colestation, but I suspect the counter clockwise position is to turn the glow plugs on. Hold it in that postion and the glow plug indicator should heat up. Once it gets hot, then turn it to the right and start the tractor. Worth a shot!