merrickvilleguy
Gold Member
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My dealer got back to me about the mf1635 saying that 12lbs is about right for ag tires that are loaded ... that's down from the 20 in the manual for air only ... who knew ?
Air Pressure in Loaded tires.
- Thread starter ruralruss
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RoyJackson
Rest in Peace
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- John Deere 4052R Cab,, Deere 855D UTV, Z920A Zero Turn Mower and assorted implements
Valve cores (the spring loaded pin inside the stem) do wear and can result in slow leaks.
Also, cold weather can cause a pressure drop.
There's two reasons to check pressure at least occasionally.
Also, cold weather can cause a pressure drop.
There's two reasons to check pressure at least occasionally.
riptides
Super Member
Ditto.
I made the mistake of rolling out in last years blizzard without eye-balling my tires. I got half-way down the driveway when I noticed, there's a lot of water around here! HAH!
After the dealer helped me out, I check on a regular basis now. Just make sure your valve stem is above the fluid level when you check.
Soundguy
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- RK 55HC,ym1700, NH7610S, Ford 8N, 2N, NAA, 660, 850 x2, 541, 950, 941D, 951, 2000, 3000, 4000, 4600, 5000, 740, IH 'C' 'H', CUB, John Deere 'B', allis 'G', case VAC
air pressure is air pressure.. run whatever pressure the tractor calls for.
since air can be compressed SOOOOOOO much.. whatever air volume you have in the tire is the max compressible space and that is how much give the tire has when it needs to deform.
loading to 75% should be fine for most applications.
soundguy
since air can be compressed SOOOOOOO much.. whatever air volume you have in the tire is the max compressible space and that is how much give the tire has when it needs to deform.
loading to 75% should be fine for most applications.
soundguy
Mace Canute
Elite Member
I've posted this before...from Installing Liquid Ballast in Tires | Gempler's
"Tires are designed to operate at maximum efficiency when they are at their Rated Deflection. With the tractor on a hard surface, deflection is the distance from the axle center to the ground surface divided by the distance from the axle center to the top of the tire. In technical terms, deflection is the value of the loaded radius of the tire compared to the unloaded radius. Rated deflection is the amount of deflection when the tire is deformed to its optimum or design footprint. Rated deflection for radial tires is about 85%, for bias tires it is about 90%. The correct pressure to achieve rated deflection depends on the load the tire is carrying. A correctly inflated radial tire will have a significant sidewall bulge or "cheek'. It may look low or flat but it is not. If you inflate a radial tire by "eyeball" until the sidewall bulge looks like that of a bias ply tire, you lose most of the performance advantages of the radial tire.
The tire gauge you use and the way you use it can have a big effect on what you think the tire pressure is. Always start with a good gauge, one that costs money, is easy to read, and is graduated in 1 psi increments. If your gauge cost 99 cents or came free from a feed dealer, has marks every 5 psi from 0 to 100 psi, and looks like it will break if you drop it, you are probably not going to measure pressures accurately.
Ideally, tire pressures should be measured in the morning, cold, or when the the tractor has not been used for several hours. As a tractor is used and the tires warm up, tire pressures will increase from 1 to 3 psi.
If tires have fluid ballast in them, the pressures at the bottom of the tire can be as much as 1.5 psi higher than at the top, depending on the amount of ballast. Whether you measure at the top or the bottom doesn't matter as much as whether you are consistent in where you measure. It is less messy if you measure with the valve stem at the top but it may be slightly more accurate if you measure with the valve stem at the bottom."
For anybody contemplating filling their own tires for the first time, this site gives some good step by step instructions with pics Installing Liquid Ballast in Tires | Gempler's
There is quite a bit of good information in this site Installing Liquid Ballast in Tires | Gempler's and this site http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/eng9920
"Tires are designed to operate at maximum efficiency when they are at their Rated Deflection. With the tractor on a hard surface, deflection is the distance from the axle center to the ground surface divided by the distance from the axle center to the top of the tire. In technical terms, deflection is the value of the loaded radius of the tire compared to the unloaded radius. Rated deflection is the amount of deflection when the tire is deformed to its optimum or design footprint. Rated deflection for radial tires is about 85%, for bias tires it is about 90%. The correct pressure to achieve rated deflection depends on the load the tire is carrying. A correctly inflated radial tire will have a significant sidewall bulge or "cheek'. It may look low or flat but it is not. If you inflate a radial tire by "eyeball" until the sidewall bulge looks like that of a bias ply tire, you lose most of the performance advantages of the radial tire.
The tire gauge you use and the way you use it can have a big effect on what you think the tire pressure is. Always start with a good gauge, one that costs money, is easy to read, and is graduated in 1 psi increments. If your gauge cost 99 cents or came free from a feed dealer, has marks every 5 psi from 0 to 100 psi, and looks like it will break if you drop it, you are probably not going to measure pressures accurately.
Ideally, tire pressures should be measured in the morning, cold, or when the the tractor has not been used for several hours. As a tractor is used and the tires warm up, tire pressures will increase from 1 to 3 psi.
If tires have fluid ballast in them, the pressures at the bottom of the tire can be as much as 1.5 psi higher than at the top, depending on the amount of ballast. Whether you measure at the top or the bottom doesn't matter as much as whether you are consistent in where you measure. It is less messy if you measure with the valve stem at the top but it may be slightly more accurate if you measure with the valve stem at the bottom."
For anybody contemplating filling their own tires for the first time, this site gives some good step by step instructions with pics Installing Liquid Ballast in Tires | Gempler's
There is quite a bit of good information in this site Installing Liquid Ballast in Tires | Gempler's and this site http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/eng9920
Soundguy
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- RK 55HC,ym1700, NH7610S, Ford 8N, 2N, NAA, 660, 850 x2, 541, 950, 941D, 951, 2000, 3000, 4000, 4600, 5000, 740, IH 'C' 'H', CUB, John Deere 'B', allis 'G', case VAC
And just think.. since loaded tires have been in existance.. most farmers simply fill them.. leave an air space, and pressureize as normal... and nothing much bad happens... some stuff CAN be thought out just a lil too much...
soundguy
soundguy
Don87
Elite Member
IMHO, look at your tires when you put them on the tractor(this does not include radial tires).
All the tread should contact the ground(thats where you get your traction).
Fill the tire with fluid, air it up(on a hard surface), you want just enough air to keep all the tread straight on the ground(again....traction).
If too little air, sides will wear out..........too much air, centers will wear out.
Less traction with either scenario.
Edit: After I got my tires fill with Rimguard, I put them on the tractor, and the center of the tread was 'bulged'. I let some air out til the tires sat flat on the concrete, then checked the pressure.......almost perfect with maufacturer specs.
There have been reports of 'tire slippage' with rimguard, I'll bet a dollar to a doughnut, that those people ran less air than factory specs.
All the tread should contact the ground(thats where you get your traction).
Fill the tire with fluid, air it up(on a hard surface), you want just enough air to keep all the tread straight on the ground(again....traction).
If too little air, sides will wear out..........too much air, centers will wear out.
Less traction with either scenario.
Edit: After I got my tires fill with Rimguard, I put them on the tractor, and the center of the tread was 'bulged'. I let some air out til the tires sat flat on the concrete, then checked the pressure.......almost perfect with maufacturer specs.
There have been reports of 'tire slippage' with rimguard, I'll bet a dollar to a doughnut, that those people ran less air than factory specs.
RobertN
Super Member
Don't forget, you have to change from summer air to winter air, and vica versa too. The overall density of the air changes due to seasonal variations, solar flare, and the secondary charge on the flux capacitor.
riptides
Super Member
Good points.
I see this as another synthetic - real oil/lubricants issue. I'll have to jump out as my analytical skills will be taxed....