Cold weather start, with glow plugs and block heater. Why does my tractor not start at minus 20 C?

[ray66v]

When it's that cold, even with a block heater the crankshaft and rotating groups for the hydrostatic system is facing huge resistance from honey-thick fluids in the journals and passages.

Most HST fluid is 30w or less, so it doesn't get quite that thick unless you are going below -20F. But yeah, it's certainly a drag on the engine.

I do use a small silicone pad heater on the bottom of the differential. It keeps the fluid from being affected by the cold, and reduces the published warm up times.

 

[Solution MF 4707]

Yeah, that's a bit nippy!
Is the tractor inside a shed or barn? That would help.
Did you switch to a lower weight synthetic oil for those temps?
Do you treat your fuel?
If outside, you could cover it with a tarp.
You may need an oil pan warmer.
As suggested, a battery tender would help, plus insulating the battery.

Thanks. Good recommendations. Covering with a tarp and oil pan warmer and battery tender would probably do it.
I may also change the oil to a 10-40 instead of a 15-40. The tractor is in a barn, but it is not heated.

 

[Solution MF 4707]

When it's that cold, even with a block heater the crankshaft and rotating groups for the hydrostatic system is facing huge resistance from honey-thick fluids in the journals and passages.
If you can tarp the whole thing and heat it with a frost fighter for a while, it should turn over a lot easier.

Makes sense! Yes, I found out that the block heater alone does not do it. I have to get one number lighter oil in there and make sure that the battery is full, etc.

 

[JWR]

You can calculate them from the extrapolated viscosity values at whatever temperature you wish. Can only calculate relative values. Cannot calculate actual cranking speed.

I understand relative or proportional to viscosity and all that but it sounds far fetched, essentially guessing, to me that you can compute in an example that 100 rpm with one viscosity will result in 160 rpm with some other viscosity. How about an example of that calculation? There are a large number of relevant variables.

 

[RalphVa]

Get that 15w40 goo out of the crankcase.

 

[Mattsy Fergy]

Fortunately, it is inside, that will help. You can get a small torpedo style heater, they make them in propane or kerosene/diesel, and aim the heat up under the motor. let it warm for a while until the block feels warm, then try to start it. Once you get it warmed up, change the oil to a lighter grade synthetic.
A SMALL shot of starting fluid, NOT ether, might help to get it going. Go easy on that, it seems like once they get a taste for it they always need it.

 

[Jofang]

If you remove the air filter so you have direct access to the air suction inlet, stuff a couple of sheets of newspaper or similar up the air intake and set fire to them whilst cranking. Guaranteed solution in any weather.

 

[Dmacleo]

If you remove the air filter so you have direct access to the air suction inlet, stuff a couple of sheets of newspaper or similar up the air intake and set fire to them whilst cranking. Guaranteed solution in any weather.

mines plastic so....heated air does help but use this trick carefully.

 

[Jofang]

Dmacleo is spot on, use this carefully if you have a plastic inlet. Going back 40 years or more we used to start the old diesels this way before glow plugs were invented. Light the paper immediately before cranking.

 

[panamaguy]

After living in Canada most of my life and owning many gas and diesel engine things I honestly believe that the best thing you can do for a engine in cold starts is have a oil pan heating blanket. Block heaters are needed also but all they do is heat the block, the oil pan hangs below the block and is full of thick as honey oil. Thick oil does not flow fast enough to the top end. Remember heat rises so start heating at the very bottom,,,, your oil pan