My Kubota B2150 will not start. The battery tests fine, but the glow plug light does not light up and the tractor will not try to start.

It seems like you have already checked most of the common causes of a non-starting engine. However, there are still a few things you can try:

Check the fuel system: Make sure that the fuel pump is working properly and that there is fuel in the tank. You can also check the fuel filter to see if it's clogged.

Check the battery: Even though you have two batteries, it's possible that one or both of them are not providing enough power to start the engine. You can have the batteries tested to make sure they are in good condition.

Check the glow plugs: If the glow plugs are not working properly, it can cause the engine to have trouble starting. You can have the glow plugs tested to see if they are functioning correctly.

Check the compression: If the engine has low compression, it can cause it to have trouble starting. You can have the compression tested to see if it's within the manufacturer's specifications.

If none of these suggestions work, it might be best to take your vehicle to a certified mechanic who can diagnose the issue more accurately.

How about the ignition starter switch? It may have a bad a connection internally.

[PDF]KUBOTA DIESEL ENGINE - Waterax

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engine maintenance. it is KUBOTA's policy to utilize as quickly as possible .... Be sure to close the coolant drain valve, secure the pressure cap. and fasten the .... Oil drain plug. (18) Oil ... around the machine. it may catch on moving (B) "OFF".

Kubota V2203 Block Water Drain? - Diesel Bombers

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Nov 21, 2013 - On my Kubota V2203 DI above the Oil filter is a long bolt of which the only thing ... I did not even know that Block Water Drain was there till last night I ...Also, the pipe plugs in the engine are a Japanese style, but we've ... Kubota v2203 vsv1902, ziegler, Diesel Engine Conversions, 4, 01-10-2015 06:27 PM.

Kubota Engine Service Tips

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If the reading is 11 volts or more while you are trying to crank the engine see the ...Other causes include defective glow plugs or low cranking speeds from a weak battery.... We have not seen it "ruin" anyone's tractor yet, so drain the tank, refill with ....passages between the cylinder head and the block became 90% blocked.

Kubota L2550 needs block heater! - Yesterday's Tractors

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Jan 25, 2011 - 25 posts - ‎14 authors

Oldmax, I could swear I was looking at a closeup of my engine, except for the colour.... V1702, V1703, V1902, V1903, V2003, V2003T, V2203 (4 cylinder) Part No. ... BSeries (Except 2 cylinder) Part No. Watt Volt Diameter Type .... Paul, does the tractor have a block drain plug, and a thermostat bypass ...

81418784532&item=281418784532">G1900 Kubota, the glow plugs are energized when the keyswitch is moved halfway to the start position. Also the glow plug indicator light is illuminated when in this position. I hold the key in that position until the glow plug light goes out, and then crank the engine. On really cold days I repeat the glow plug cycle several times before cranking.

Make sure no check engine light. If light on run diagnostic prior to testing. If no check eng. light and no start when cold, could be bad glow plugs, Take test light from positive side of battery to each glow plug post (unplug from harness before testing) if test light lights plug good . if plugs good check pump mounted driver (scan tool required) if P.M.D. good run test for optical sensor in injector pump (scan tool required). Known failure points. I am working on assumption fuel pressure tested between lift pump and injector pump. Look for white smoke when cranking, if present fuel entering cylinders. I can't offer anymore help without further info. Hope this helps.

You would need to check the glow plug timer circuit and the fuel supply. Diesel glow plugs can wear out. Make sure the "Ready light" is working and that you hear the timer cycling. Usually the lights will dim as the power goes to the glow plugs.

The glow plug wire can be checked with a Voltmeter inserted on a wire from the Relay timer. The glow plugs are tested when they are removed from the engine. If you get this far, you can use battery cables to test them. They can melt. Ask for more details about proper procedure.

Hello philkatkiele: My name is Roger and I will help you. First thing you need to check is the glow plugs. They will need tested individually. Un plug all 8 glow plugs. Take a test light and hook end to the positive battery cable. Touch opposite end of test light to the terminal end of the glow plug. The test light should light. Touch all 8 glow plugs. Ant that do not light are bad and will need replaced. If glow plugs are burnt out then the controller will flash wait light to early or very fast. The wait light should be on for approximately 10 seconds.If al glow plugs check ok then I would suspect the glow plug controller as the problem. Also if the temperature out side is below 40 degrees the truck should be plugged in. This will help to make the engine start easier. Should you need further help please just ask.Please rate the answer as this way I know it was helpful. Thank You for using Fix Ya. Roger

The glow plug relay is responsible for the duration of glow plugs, this needs to be the starting point. You should get a 12v out for so many seconds when ignition is switched on.
I have taken the cover off relays in the past, cleaned up the internals, sprayed with circuit cleaner and got plenty more years out of them, worth a try.

You can get the error codes from the ecu. Many auto parts stores will loan a meter to do it.
Also test the glow plugs using the vehicles system. Do them individually.