Very cold starts

Morks

Morks

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A little backstory to this post. I am a very avid outdoorsman. With that, I travel to Northern Ontario frequently, chasing the next big fish etc... Never thought about this topic much before owning my own vehicle, the tj. To anyone of you avid anglers, you may think this seems fun, but for everyone else not so much. During the winters I ice camp. Meaning I choose a certain lake or whatever the case is, I setup a portable ice hut with a buddy heater, a cot and fish crazy hard for as long as the trip lasts. While I do this my tj sits on the side of a road/trail in freezing temps for days on end. May not seem to bad, however I had a trip last yr where the average temp over the 3 days I was out was -40 before windchill. Might I add that I have not had heat since buying the vehicle as well. I am putting a heater core in this sunday! lol

With it sitting in these cold conditions I am worried about the clutch fluid freezing up and the brake fluid (I assume that the plastic pieces can break, and or the slave cylinder). However I do have the heater which I can place underneath the vehicle while I load up the snowmobile etc... and warm things up a tad (for some reason never thought about it till now). Is there anything else I can do to prevent those fluids from freezing like an antigel type product or alike.
 
-40: when it's so cold that Celsius or Fahrenheit doesn't even matter.

I'd never even thought of brake fluid freezing but I googled and sure enough, even though it doesn't technically freeze it can thicken to the point of not working, and wouldn't you know, right around -40.

I've never had to start a sitting vehicle that cold but my thought would be to take care of the engine oil so you can get it started, and then you have engine heat to help with everything else. Do you have a generator you could use to power a block heater? You could use the buddy heater to take care of the rear brakes and lines that the engine heat won't reach. Even better if you can carry a roll of something to set up as a fence around the undercarriage so the heat doesn't just blow away.

Another thing to point out is if you're running a soft top, don't plan on putting anything big behind the rear seat because that vinyl window will crack if you so much as look at it wrong.
 
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Brake fluid doesn't normally have moisture in it but it can absorb moisture over the years. To insure there's no moisture in it I'd do a complete flush of the brake system, which should be done occasionally anyway. Use a good synthetic DOT 3/4 brake fluid. Don't use DOT 5 which is incompatible.

For temps that cold I'd run a 0W-30 synthetic engine oil which can help it to start more easily in super-cold conditions. Synthetic lubricants flow better in uber-cold conditions. If your transmission lubricant hasn't been changed in a while I'd change it to a synthetic too, Redline MTL is a superb synthetic transmission lubricant that meets the specs for yours. The transfer case is likely already running on ATF+4 which is already a synthetic, unless someone changed it to something else. If you don't know it wouldn't hurt to drain it and refill it with ATF+4.

Your clutch mechanism is a sealed system and it's not easily drained/refilled. If you're really concerned about it you can buy a pre-filled/pre-bled clutch hydraulic system which includes the master and slave cylinders. It's easily replaced, it's a fairly quick bolt-in process, and it isn't that expensive. Just avoid a store brand replacement for something as critical as this.

Having lived in North Dakota for one very long winter while I was in the Air Force, I can't imagine living on the ice for several days to catch fish in -40 temps but it sounds like you're well prepared and know what you're doing. It hit -53 while I was in Grand Forks ND, never again. :eek: :ROFLMAO:
 
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freedom_in_4low said:
-40: when it's so cold that Celsius or Fahrenheit doesn't even matter.

I'd never even thought of brake fluid freezing but I googled and sure enough, even though it doesn't technically freeze it can thicken to the point of not working, and wouldn't you know, right around -40.

I've never had to start a sitting vehicle that cold but my thought would be to take care of the engine oil so you can get it started, and then you have engine heat to help with everything else. Do you have a generator you could use to power a block heater? You could use the buddy heater to take care of the rear brakes and lines that the engine heat won't reach. Even better if you can carry a roll of something to set up as a fence around the undercarriage so the heat doesn't just blow away.

Another thing to point out is if you're running a soft top, don't plan on putting anything big behind the rear seat because that vinyl window will crack if you so much as look at it wrong.
Click to expand...

"40 below, thanks, asshole!", says the generator...
 
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freedom_in_4low said:
-40: when it's so cold that Celsius or Fahrenheit doesn't even matter.

I'd never even thought of brake fluid freezing but I googled and sure enough, even though it doesn't technically freeze it can thicken to the point of not working, and wouldn't you know, right around -40.

I've never had to start a sitting vehicle that cold but my thought would be to take care of the engine oil so you can get it started, and then you have engine heat to help with everything else. Do you have a generator you could use to power a block heater? You could use the buddy heater to take care of the rear brakes and lines that the engine heat won't reach. Even better if you can carry a roll of something to set up as a fence around the undercarriage so the heat doesn't just blow away.

Another thing to point out is if you're running a soft top, don't plan on putting anything big behind the rear seat because that vinyl window will crack if you so much as look at it wrong.
Click to expand...

Yeah, I have thought about grabbing a smaller generator for this issue, as you know space is the issue... I am not too worried about the engine oil so to speak as the buddy heater would be sufficient, which I have no doubt. Just hoping that the slave cylinder would warm up with that (I think it should). Definitely put the hard top on around this time, 1 because the rods and hunting gear are in the jeep all the time and 2 the cracking windows issue. or else id be running down the freeway with snow pants and a coat topless!
 
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Jerry Bransford said:
Brake fluid doesn't normally have moisture in it but it can absorb moisture over the years. To insure there's no moisture in it I'd do a complete flush of the brake system, which should be done occasionally anyway. Use a good synthetic DOT 3/4 brake fluid. Don't use DOT 5 which is incompatible.

For temps that cold I'd run a 0W-30 synthetic engine oil which can help it to start more easily in super-cold conditions. Synthetic lubricants flow better in uber-cold conditions. If your transmission lubricant hasn't been changed in a while I'd change it to a synthetic too, Redline MTL is a superb synthetic transmission lubricant that meets the specs for yours. The transfer case is likely already running on ATF+4 which is already a synthetic, unless someone changed it to something else. If you don't know it wouldn't hurt to drain it and refill it with ATF+4.

Your clutch mechanism is a sealed system and it's not easily drained/refilled. If you're really concerned about it you can buy a pre-filled/pre-bled clutch hydraulic system which includes the master and slave cylinders. It's easily replaced, it's a fairly quick bolt-in process, and it isn't that expensive. Just avoid a store brand replacement for something as critical as this.

Having lived in North Dakota for one very long winter while I was in the Air Force, I can't imagine living on the ice for several days to catch fish in -40 temps but it sounds like you're well prepared and know what you're doing. It hit -53 while I was in Grand Forks ND, never again. :eek: :ROFLMAO:
Click to expand...

Doing the amount of work I did this summer all the fluids are new, which is nice. As for the master/slave cylinder, I bought a good pre-bled unit last fall as it was starting to go out on me... Should I be concerned about the lines/cylinders breaking when I go to press it when I start it (if I did not warm it up)? It is not as bad as it seems, I know lots of people who don't like fishing so obviously, it would suck to them. But there is just something about plowing the jeep in a snow bank and snowmobiling deep in the bush that is awesome! The tent stays in the 60s or higher all night so plenty warm!
 
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Morks said:
Doing the amount of work I did this summer all the fluids are new, which is nice. As for the master/slave cylinder, I bought a good pre-bled unit last fall as it was starting to go out on me... Should I be concerned about the lines/cylinders breaking when I go to press it when I start it (if I did not warm it up)? It is not as bad as it seems, I know lots of people who don't like fishing so obviously, it would suck to them. But there is just something about plowing the jeep in a snow bank and snowmobiling deep in the bush that is awesome! The tent stays in the 60s or higher all night so plenty warm!
Click to expand...

Bypass the clutch interlock switch , start your Jeep without pushing the clutch in . , ( In neutral of course ) enjoy looking at God's creation for 20 minutes ,
be on your way after warm up. Glad to see not everyone only uses their jeep in the summer , top off , crawling on washing machine size rocks etc..
Sometimes I feel I am the only one who doesn't follow the summer toy model . Enjoy your Jeep!
 
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Morks said:
Yeah, I have thought about grabbing a smaller generator for this issue, as you know space is the issue... I am not too worried about the engine oil so to speak as the buddy heater would be sufficient, which I have no doubt. Just hoping that the slave cylinder would warm up with that (I think it should). Definitely put the hard top on around this time, 1 because the rods and hunting gear are in the jeep all the time and 2 the cracking windows issue. or else id be running down the freeway with snow pants and a coat topless!
Click to expand...

If the engine oil is ok then the clutch probably would be too. I'd be more concerned about the rear brakes, like if you hit the pedal and forced thick brake fluid into the calipers and then the calipers stick because it won't push the fluid back out. I guess it's probably a self correcting problem though, as the calipers heat up form dragging...
 
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Having spent 6 year in the Territories and seeing -45 fairly regularly I really wouldn't worry about that too much. The things your most likely to have issues with is your fuel freezing off if it gets water in it, they make a gas line antifreeze additive. Your battery freezing if it's not in good shape and all the driveline lube getting way thick and not circulating properly. Swap all the drive line fluids to synthetic. Make sure your battery is in really good shape before heading out and if in a really remote location maybe go to a dual isolated battery setup. And if really concerned about it you can look into installing a Espar style heating system they run independently off a thermostat, remote, or programing based on model and run periodically to heat the engine, cabin and other tied in systems without running the engine. They are used pretty extensively in the oil patch when guys are leaving vehicles unplugged and sitting for extended periods in the deep cold.

I had a fully propane converted 87 silverado up there that the fuel would freeze off if you so much as glanced at it while going through the start up and warm up routine. It never once had an issue with the brakes or clutch in the cold but the power steering, Trans, transfer case and diffs were not real happy at those Temps so you need to go easy on them until warmed up and a winter front or even a piece of cardboard in front of the rad helps, just make sure you pull it once your back above -20.
 
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ColoJeep said:
Bypass the clutch interlock switch , start your Jeep without pushing the clutch in . , ( In neutral of course ) enjoy looking at God's creation for 20 minutes ,
be on your way after warm up. Glad to see not everyone only uses their jeep in the summer , top off , crawling on washing machine size rocks etc..
Sometimes I feel I am the only one who doesn't follow the summer toy model . Enjoy your Jeep!
Click to expand...

I have mine bypassed... don't use the clutch all summer to start. Figured the jeeps starter has to turn more to actually get the vehicle running like that...? So when it is really cold I press the clutch to give it an easier time turning things over. Am I overthinking that? Also, this jeep does everything, DD duty, and hauls a snowmobile all over the province. Not many buddies or people near me drive it like that either, although a truck would be amazing, it is too much fun to drive, and know I can fix things anywhere to not want to use it!
 
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Shandara said:
Having spent 6 year in the Territories and seeing -45 fairly regularly I really wouldn't worry about that too much. The things your most likely to have issues with is your fuel freezing off if it gets water in it, they make a gas line antifreeze additive. Your battery freezing if it's not in good shape and all the driveline lube getting way thick and not circulating properly. Swap all the drive line fluids to synthetic. Make sure your battery is in really good shape before heading out and if in a really remote location maybe go to a dual isolated battery setup. And if really concerned about it you can look into installing a Espar style heating system they run independently off a thermostat, remote, or programing based on model and run periodically to heat the engine, cabin and other tied in systems without running the engine. They are used pretty extensively in the oil patch when guys are leaving vehicles unplugged and sitting for extended periods in the deep cold.

I had a fully propane converted 87 silverado up there that the fuel would freeze off if you so much as glanced at it while going through the start up and warm up routine. It never once had an issue with the brakes or clutch in the cold but the power steering, Trans, transfer case and diffs were not real happy at those Temps so you need to go easy on them until warmed up and a winter front or even a piece of cardboard in front of the rad helps, just make sure you pull it once your back above -20.
Click to expand...

Good to know about the additive for the gas and the other problem areas I mentioned. Living up in the territories would be awesome!
 
Another thing to consider is to put the transfer case in neutral and leave the transmission in gear during engine warm-up.
That will get the tranny and transfer-case fluids warm as well.
It also makes a world of difference how the manual tranny shifts during the initial driving.
 
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Vinman said:
Another thing to consider is to put the transfer case in neutral and leave the transmission in gear during engine warm-up.
That will get the tranny and transfer-case fluids warm as well.
It also makes a world of difference how the manual tranny shifts during the initial driving.
Click to expand...

Never thought about that, great idea!
 
Vinman said:
Another thing to consider is to put the transfer case in neutral and leave the transmission in gear during engine warm-up.
That will get the tranny and transfer-case fluids warm as well.
It also makes a world of difference how the manual tranny shifts during the initial driving.
Click to expand...

Honest question because I really don't know, but given that the t case pump is on the output shaft, should one worry about running the input shaft for an extended period without the pump?
 
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freedom_in_4low said:
Honest question because I really don't know, but given that the t case pump is on the output shaft, should one worry about running the input shaft for an extended period without the pump?
Click to expand...

I know what you’re saying but there is no load on the gears just spinning free. I’ve warmed up my previous TJ’s using the method I described many times and have never had an issue.
 
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freedom_in_4low said:
Honest question because I really don't know, but given that the t case pump is on the output shaft, should one worry about running the input shaft for an extended period without the pump?
Click to expand...

For what it's worth we used to do this all the time in the 1980's on Chevy CH465 / 205 and CH465 / 203 and SM 420 / T-221 trans / T cases.
10-15 minutes at a time. Never had a issue.
 
Vinman said:
I know what you’re saying but there is no load on the gears just spinning free. I’ve warmed up my previous TJ’s using the method I described many times and have never had an issue.
Click to expand...

Thinking more about it that makes sense. Idling in first gear it's gonna be doing less than 4 revs per second.
 
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