Mahindra 28XL - White Smoke, Won't Wtart

[RomeoKilo]

Mahindra 28XL
Inexperienced tractor owner here. I recently went to start it and it won’t start. Engine turns over and I get puffs of white smoke. The white smoke actually puffs pretty good with each turn of the engine but then trickles out slowly for 2-4 minutes afterwards. I’ve already installed a new fuel filter as well as glow plugs. I also sanded connections on bus bar and ensured nuts are tight. Any ideas on what to try next?

This sounds really weird to me but the battery and wire to glow plug bus bar measures right around 12.5 volts. When I connect the wire to the bus bar I get 30 volts. Shouldn’t this read 12.5 also or just under? Why would it read more than double?

 

[Wagtail]

G'day Mate and welcome to TBN from Downunder.

White smoke typically indicates that there is water in your fuel. Check your fuel bowl/fuel tank (inspection camera for the latter).

Enjoy the site... from wherever in the world you are.

 

[MAX-24-Dean]

When white smoke happens at cold start and then disappears as the engine warms up, the most common causes are fouling deposits around piston rings and/or cylinder glazing.

How many hours on the meter?

White smoke can be also be caused by raw, unburnt fuel passing into the exhaust stream. Common causes include:
Incorrect fuel injection timing;
Defective fuel injectors;
Low cylinder compression.

 

[LouNY]

White smoke on a cold start is just unburnt fuel.
I expect you have an issue with your glow plugs.
Measuring the voltage at the glow plugs when they should be on, your measurement should be considerable less then 12.5 volt.
Is your meter set for DC volts and are you measuring from hot to ground, wire to ground, glow plugs and bus bar to ground.
It would not hurt to measure those twice once to the negative battery terminal and once to the engine ground.
They should be the same.

 

[Roadworthy]

Welcome to TBN. I like to start with the basics. Check your air filter and ensure a clear air path to the intake manifold. I can't buy thirty volts at the glow plugs. You can't source that much voltage. They normally get about 10.5 volts. If you really had thirty they're probably toast.

 

[RomeoKilo]

Thanks all for the replies. I'll re-check the voltage at the glow plugs again. Its got just over 500 hours. I picked up some diesel 911 to run through the fuel system. I'll also get an air filter on order as well and see what happens.

 

[RomeoKilo]

Ding Ding. Roadworthy is the winner. I took the air filter off and she started up. Thanks everyone for their input and I'm glad it was an easy fix. I had no idea that a dirty air filter would cause a diesel to stop working almost over night.

 

[Wagtail]

Good stuff... and thank you for letting us know.

 

[big bubba]

good to see a problem solved on this forum, a win win for the OP & forum

 

[RomeoKilo]

I still don't understand my multimeter reading 30 volts to the glowplugs and 12.5 at the battery. I think thats going to be a user error on a new multimeter that has some "auto" settings. I'm most likely using it wrong / reading it wrong.