How to determine freezing point?

[Workerbee]

Tractor came in from out east (Virginia) with the rear tires loaded with methanol. How would one determine what the freezing point of that methanol mix is?
Im tempted to drain it all and bolt cast weights to the wheels, which would be spendy. But it’d be less dollars than driving those tires with ice in them.
Or would it be advisable to drain say half of the mix out and add something strong to refill them?

 

[imnukensc]

No way to tell the concentration in your tires without some analysis I suppose, but here's a table that might help.

Methanol Freeze Protected Heat Transfer Liquids

Freezing and flash points for methanol or methyl based heat-transfer fluids or brines.

www.engineeringtoolbox.com

 

[BigG]

How do you know what is in the tires?

 

[Workerbee]

Thats interesting about the freeze point and flash point by concentration. Id assume I could drain some and add as close to pure methanol as I could find to arrive at a safe level for freezing here where -30 can happen fairly easily. But looking at the flash point at that concentration level it would be pretty low, like in much less than normal summertime temps here. What are the chances of an ignition source inside a tire?
I know its methanol because the dealer told me it was likely that, as most ballast in that region is. Its clear and smells like alcohol soI assume he wasnt kidding.

 

[Palmettokat]

You probably will have to break the tire from the rim to get it all out or if tubed maybe replace it, I think. Do you know if the tractor was used in the winter or not? Here people use to not be concerned on farm tractor not used in winter but our getting in to the teens is very seldom and not for long. Did you ask the dealer for suggestion on knowing the freeze point and mixture ratios? Seems like he would be a good source.

 

[Workerbee]

I did ask the dealer and he said its hard to know what ratio it was put in at. I am pretty certain it wasnt used in any sort of winter like we have up here. I did ask an old friend who has managed an ag tire shop for 45 years. He told me the same thing, that if not used its not an issue, but dont drive on a frozen tire or itll be ruined in a hurry. This one will certainly be used in the winter. He knew everything about calcium chloride but had no knowledge about methanol or how it could be tested for a freeze point.
Is it possible to drain it without breaking the beads?

 

[SidecarFlip]

Only way I know of to determine the concentration of methanol in the tire is pull a small sample and use a Refractometer to determine the concentration ratio and then refer to a table showing showing the specific gravity (concentration of methanol to water) to determine the freeze point) They are not expensive. I have one in the shop and use it all the time.

 

[D2Cat]

Why not drain a bit in a plastic butter dish, put it in your freezer and see what happens before you do draining/adding?

 

[Workerbee]

Thanks Flip and D-2! I dont have a refractometer but do have a freezer here. I will give that a try.
What all do you use one of those for Flip?

 

[Workerbee]

On further thought about the freezer tip. If the mix fails to freeze it really only tells me that its good to zero or 20 or whatever degree our freezer goes to. Not really a way to tell what temperature it would freeze at or if its good to 20 below. Maybe I had better learn about refractometers...

 

[D2Cat]

You're going to analyze until you're paralyzed.

 

[Schmitty]

Another option:

-Remove a small portion (1 oz or less) and try to ignite it in a flat dish/plate; if it produces a faint blue flame and stays lit for a little while, then the solution is likely >40% methanol. Do this is a dark room/garage and only do this is you are comfortable around fire/flames and have a way to put the fire out once started. If this does ignite, the current mixture shouldn't freeze until -40°F (or °C ) or lower. If it doesn't ignite, you may have a better chance of freezing it in a normal kitchen freezer to perform D2Cat's test. If the small portion of liquid burns all the way until it's gone, I'd bet you likely have near 100% methanol.

You can also put a thermometer in your freezer to see what temperature it actually is at or can get down to and/or you can crank it down to the coldest setting temporarily for this experiment.

 

[Palmettokat]

No idea about mixing your current mixture with another but you can drain your tires without breaking the bead as low as the valve stem is turn down. You could refill with plain water and drain again diluting it. If it were me I would support the rear end to prevent collapsing the tire itself but collapsing it would push more out. No idea how that might harm the tire.

 

[Workerbee]

Thanks Palmettokat, We have decided to do as you say, jack the rear end up one side at a time, and remove the valve core and let them drain. I havent gotten to it yet, but I think I can stick a small plastic hose line down through the valve stem and hook it up to a self priming pump, then to a vacuum pump to get it all out. Then just going to go with oem cast iron weights.

 

[Palmettokat]

Look at your valve stem carefully. Some are what I called two parts and the part with the valve in it will screw off for draining and filling the tire. I am sure you know to at least remove the valve stem. No idea if the solution in the tires will kill vegetation or not but you may wish to check on that before you drain the tires.

 

[JeffL]

Why don't you just weigh it and compare it to an equal volume of water. Specific gravity of water is 1 and methanol is 0.79; so volume of 10 lbs of pure water and same volume of methanol would weigh 7.9 lbs. If your mix weighed 8.95 lbs then your mix is 50%. A gallon of water weight 8.34 lbs.

 

[Workerbee]

Now theres a method even I could do. I will drain a small jar, pint or whatever, and weigh it on my postal scale, compare the weight to the same jar filled with water, and do the math. (I know maff’s hard!)
Thanks Jeff