Fx24D weigh-in

Mickey_Fx · Nov 14, 2006

Being a old M.E. with **** tendencies I had to find out what my tractor weighed. There were several BIG surprises after the weigh-in and some caclulations made.

Weigh-in conditions = Me sitting in the seat, quick mount hitch installed but no implement and empty FEL. Ernie told me when I purchased the tractor the tires were filled with calcium solution. Digital scale with 10-20 lb resolution.

Front = 2140#
Rear = 1760#
Total = 3900# (this is the sum of front and rear axles and separate reading of complete tractor)

The calculations:
Center of gravity with no additional weight is 13" in front of the front axle. Not good IMO. The front axle is exactly mid-way between the center of the bucket and the rear axle. Due to FEL dims and weight transfer, for every pound placed in the bucket, the front axle see's 2 additional pounds.

With tires rated for ~900# each, the weigh-in alone show they are overloaded without anything in the bucket. The calculations and the actual weigh-in is saying quite clearly to me, "the tractor is unstable" due to fwd positon of the CoG.

Suggest others with FEL's on their tractor, get them weighed, do some calculations and see what the situation is for your tractor. You may be as surprised and I was.

roxynoodle · Nov 14, 2006

I'm pretty sure my tractor is similar to yours and that's why my front tires are garbage. I've been waiting 5 weeks now for new front tires that were supposed to take 10 days to come in. Your calculations don't surprise me in the least.

scrinch · Nov 14, 2006

Your CG is NOT in front of your front axle. If it was, your tractor would tip up on its front two wheels until the bucket stopped it! And you would have a negative rear axle load. If your axles are about 80" apart, then your CG is about 44" in front of your rear axle...or about 5% in front of midway between the axles. And I don't believe that any weight inside your tires counts toward the their weight-bearing rating. I think their weight rating is for weight transferred from the rim to the tire, not weight inside the tire which only really loads the tread. But that doesn't really matter if your front tires aren't filled with calcium solution.

tallyho8 · Nov 14, 2006

Mickey_Fx said:
Front = 2140#
Rear = 1760#
Total = 3900# (this is the sum of front and rear axles and separate reading of complete tractor)
The calculations:
Center of gravity with no additional weight is 13" in front of the front axle. Not good IMO.

I am sorry but I do not agree with your figures. If your figures were correct, to jack up the tractor. evenly, off the ground, then you would have to place the jack 13" IN FRONT OF THE FRONT AXLE. This could not possibly be the center of gravity. I will check on the wheelbase of the tractor and brush up on my math and figure where the true center of gravity is for you. If I am wrong, I know that the experts on this forum will correct me quickly.

Click to expand...

tallyho8 · Nov 14, 2006

Scrinch was able to figure it out faster than I was. I agree that the center of gravity is about 5% in front of the midpoint between your rear axle and front axle.

roxynoodle · Nov 15, 2006

Not to hijack this thread, but since I'm getting new tires anyway, should I have those foam filled? I thought the foam might cause them to wear sooner. I don't know that I want calcium chloride. It is in the rear tires of my H and I have been told to move the tractor daily if it is below freezing or it will get tire hop. It is also difficult to park it in a spot it barely fits in and get both valve stems at the tops of the tires.

My loader has curved arms and sticks out farther in front of the tractor than the traditional design loaders do. My front tires weren't very good to begin with but now they are ready to fall off the rims at any moment.

normde2001 · Nov 15, 2006

tallyho8 said:
Scrinch was able to figure it out faster than I was. I agree that the center of gravity is about 5% in front of the midpoint between your rear axle and front axle.

But guys, assuming M.E. stands for mechanical engineer, how can this be?

buppy69 · Nov 15, 2006

HUH?

Eugene

tallyho8 · Nov 15, 2006

normde2001 said:
But guys, assuming M.E. stands for mechanical engineer, how can this be?

Even an engineer can make a casual mistake now and then. Look at the engineers down in the New Orleans area who designed our levees!!!

Mickey_Fx · Nov 15, 2006

scrinch said:
Your CG is NOT in front of your front axle. If it was, your tractor would tip up on its front two wheels until the bucket stopped it! And you would have a negative rear axle load. ...

Boy, was I having a senior moment. Underlaying problem was with the spreadsheet I started last month with focus on front axle loading and identified the CoG as being from the front axle when infact the calc was based on mid-point of wheel base. The 13" figure is correct but referenced from wrong place. Due to the short 60" WB the CoG is 17" aft of the front axle. Must have been brain dead not to instantly see and know the CoG couldn't be in front of front axle. Rest of calculations for front axle loading looks to be good. Oh, on this setup, the center of the bucket to front axle is also 60".

Thanks for thumping me up side the head. I hate it when obvious things like this gets past me. Getting old isn't for the faint of heart.

scrinch · Nov 15, 2006

Boy, was I having a senior moment.

Have 'em all the time. Even had them when I was young!

mark777 · Nov 15, 2006

LOL.......interesting. I thought immediately of a front 3PH......and a Rear End Loader. It's OK Mickey, we all make mistrakes.

Ductape · Nov 15, 2006

OK...... so the front tires are NOT overloaded when the bucket is empty? Will the rating on the front tires now hold the weight the FEL is rated for?

Mickey_Fx · Nov 15, 2006

Ductape said:
OK...... so the front tires are NOT overloaded when the bucket is empty? Will the rating on the front tires now hold the weight the FEL is rated for?

No, the tires are overloaded. The scale reading given in the initial post shows this. Has nothing to do with the error I made on reference point for the CoG.

Tire rating ~900#/ea and "curb" weight, no added load shows front end at 2140#. Due to distance of the bucket to the front axle, for every pound placed in the bucket the front axle see's an additional 2# load. The tire capacity came from several tire Co's for current offerings for tires of same size and ply rating.

This was my initial intention to show one needs to be concerned with tire, wheel and axle ratings and not be focused on rated FEL capacity. On another tractor forum I frequent there have been several discussions on load capacity of FEL's on small tractors. By actually weighing my tractor and running the calculations I tried to show load rating of FEL could be the wrong target.

Jagmandave · Nov 16, 2006

But, you're gonna keep on using it anyway, cause it works just fine, right?

greatrandini · Nov 16, 2006

HEH, HEH DAVE!

Mickey_Fx · Nov 16, 2006

Jagmandave said:
But, you're gonna keep on using it anyway, cause it works just fine, right?

Yes, Normally don't pick up that much weight with the bucket. Did have the need last spring in removing a large fir that had been blown over. Was able to pick up the stump that had been trimmed down considerable. Suspect the stump was still >500#. Front tires looked almost flat and rear was very light. I crawled over to the burn pile. I would have not been surprise if one or both tires had let go. Didn't know the real facts then, only knew the load was too much and it was not a safe situation.

Do wish I could find some date on front axle capacity.

Jagmandave · Nov 16, 2006

Well, I hear you..............

My 1602D has a Koyker that I've been told by some on here is way too big for my tractor. The front tires on my Yanny are tiny to my eyes, so I'm just real careful not to put too much in the bucket, and I don't have to drive it too far with any load as my property is only about 3 acres. If I've got a bunch of weight in the bucket, I practically have it dragging on the ground...............

So I use it, carefully....................sorry for being a smart "asp".........

I always have something hanging on the 3ph, and I have weights on my back tires, but I always feel better when the much heavier brush hog is hanging on the back, it just feels more balanced...........

YanmarFever · Nov 16, 2006

Mickey, your mower weighs almost 400 lbs. and I picked it up with your tractor and the tires did not go down much. So I think your stump weighed a lot more than 500#
Ernie

Mickey_Fx · Nov 17, 2006

tractorErnie said:
Mickey, your mower weighs almost 400 lbs. and I picked it up with your tractor and the tires did not go down much. So I think your stump weighed a lot more than 500#
Ernie

I'm sure you are right Ernie. I'm thinking the stump was closer to 800# but what ever it was it was, just a guess and that why I said ">" (more than) 500#. Don't have this kind of load often but when I do, I wish there were more substantial tires on the front and a longer wheel base.