Farmall Cub

Okay, I'm loving the "mechanics" part of implements, but not the "mechanics" part of engines, though I know I did sign up for that also when I bought a Cub.

My Cub runs great, sounds great, no trouble, some smoke on a cold start but it goes away no problem. I've been starting it up to do minor things and check adjustments over the past couple weeks, all normal, but today there was more smoke (light color) and it didn't go away. Hydraulics have been great (Boss Hog rebuilt my pump), and seemed fine when I started it up today, but later I tried to lift something basic with my newly-finished 3-pt hitch, and it couldn't do it. I've got a scale between the hydraulic cylinder and rear rockshaft, and it only registered 300lbs, so no overload on the hydraulic system. The engine still sounds like it's running fine, as it always does.

Checked the dipstick -- oil is too thin, frothy white junk on the stick and inside the filler tube. A worrisome culprit is a bad hydraulic pump, leading to low hydraulic fluid, thin crankcase oil, and smoke, but I'm not convinced. All has been fine until now, recent rebuild, no hydraulic overload, and no major rise in crankcase oil. Maybe some increase, hard to tell.

Radiator is still as full as it was when I topped it off at the beginning of the winter, and no bubbles when running.

Here's my guess: Oil is thinned with condensation, making the white froth, and getting past the rings to burn up and smoke. The reason it happened today (all was fine a few days ago) is that it's been in the thirties for a while, wet, and today it's in the fifties, sunny, tractor was in an open barn, which is cooler because it's shaded. This is the first day there's been a big and long-lasting temperature difference between air and tractor.

EXCEPT, what about the hydraulic power, is this consistent with condensation? If thin oil is leading to blowby and smoke, and less power (though I didn't notice less power while driving around), maybe there's no enough power to operate the hydraulics. But trying to raise a load doesn't stall the tractor, the load just doesn't raise.

Thanks everyone for your opinions here.

Sounds like you have a whole bunch of variables here. With the 3pt lift you made, it could be that the lift point where it is built is actually putting way over the rated weight for the system. Everything works on leverage and your system you built may have that 300 pound piece of equipment actually acting like a 500 or more pound piece of equipment.

In reference to the engine and smoke, still could be a number of things. It may need sea foam run in it for awhile. Has the oil level dropped in the T/C? If so that would be a sign that it's going in the engine and could be why it won't lift. If the oil level is normal in the T/C and engine, then the pump would most likely not be the issue.

Condensation can form in the oil and climate changes will make it happen. Just check a transmission on a cub that hasn't been serviced in a few years. Lots of water.

On the frothy engine oil. Probably condensation. I'm having the same problem. Month or so ago the interior of both the shop and storage buildings looked like it had been rained on along with all the equipment.

When it gets a bit warmer, closer to mowing season I'll change the engine oil, filter, and transmission/differential fluid. No need to do the fluid change because of the high humidity, warm days and cold/freezing night temperatures.

A lot of times, running the tractor for a good hour or two (working) will get rid of the condensation and the white froth. Most of us only run our Cubs for short periods, not long enough to remove all the moisture from inside the engine block.

Condensation won't "thin" the oil. Oil and water don't mix. Water will collect at the bottom of the oil pan form condensation on the inside of the engine block. Condensation won't cause blow-by, that is caused by mechanical issues like worn cylinder walls or rings.

Hm, okay, I was imagining that when oil is circulating and being pumped, it would stir up the water from the bottom of the pan into an emulsion, which would circulate with the oil and make the oil work less well, slips by the rings, water evaporates and heads out the exhaust, etc. It did seem that there was minimal smoke upon startup, but as oil started circulating, smoke increased. I just ran it for about half an hour HOT, and smoke seemed to lessen, but didn't go away and hydraulics didn't improve.

The scale is between the hydraulic cylinder and the rear rockshaft. With the factory rockshaft, 600lbs is the max dead lift at the rear arm, and that lifting arm out the rear is more than 2x the length of the arm where the rockshaft rod connects, which means that there's an effective max weight of more than 1200lbs on the rockshaft rod. My scale read 250lbs at the rod, so I don't think I overloaded anything.

-David

Is this the first time you used your 3pt hitch, or has it worked before? I modified an old brinly tandem disc into a lift disc and couldn't lift it, I changed the hinge points and lift point a couple of inches and it came up easily. There's a fine line between the implement lifting and the back of the tractor squating down. Dale.

My opinion is to ignore the froth and smoke for the moment since they are minor issues that won't cause a drastic performance problem and can be addressed later. I think the major issue is the hydraulics won't lift squat. You mention checking the engine oil level and the radiator, but I don't see any mention of checking the hydraulic fluid level other than the engine oil level hasn't raised.

So step one for me would be to make sure the piston is in the proper position and check the hydraulic fluid level.
Yes that sentence would be shorter if I had just said what that position is, but for the benefit of those who didn't know it mattered or what the position is it will be remembered better if you have to do a little investigation.

Then, since you mention a rebuild on the hydraulic pump, if it hasn't been used a whole lot since then maybe a little air somewhere in the system, I'd make sure that wasn't an issue and then recheck the hydraulic fluid level.
Yeah, more research but I bet you remember where the piston is supposed to be .

Then I'd try lifting the three point again. If it works, great! If not unhook the rear rockshaft at the front rockshaft and put something heavy (a couple rear wheel weights, a mower deck piled up with whatever heavy you have available) under the belly of the tractor and try to lift it with just the front rocksaft. That'll tell you if it's the touch control or how you have the three point rigged.

Scrivet, thanks, yes that's my thought too -- the engine oil/smoke will clear itself up, and if it doesn't, a spring oil change will fix that.

Yes, this morning I checked the hydraulic fluid level by sticking a pinky finger in the filler hole, somebody suggested that somewhere, and came up with oil. Enough that it seemed I was reaching the reservoir oil level not just scraping some from the walls. So I think I've got enough. Also I've cycled the hydraulics plenty, even though it's seen little work, so I think there's no air in the system. Tomorrow I may try to add more oil anyway and see if it will take it -- with the piston retracted to take up its space in the block, that is!

The interesting thing here is that the hydraulics can lift more weight just after starting up the engine, and are less powerful after it's been running for a bit. There's less smoke upon startup too, so I thought that smoke (engine oil) and hydraulic power might be related.

I know too well that my 3-pt setup can drastically change the amount of effective weight to the hydraulics, and although I've thought about the relative lengths and attachment points and angles a lot, I'm not sure I've got the best setup yet. But anyway, the scale is measuring the force applied to the hydraulic rockshaft, after the hitch geometry does whatever it does. The scale should still get to reading more than 300lbs, regardless of how much heavier my hitch geometry makes the load. Maybe it can lift it and maybe it can't, but the system should still be *trying* with more than 300lbs of force.

How much should a Cub be able to dead lift with the factory rockshaft? Manual says 300 pounds is a good test weight, and that 600lbs is the max "permissible load." Does that mean it should be able to lift 600lbs on a chain hanging from the rear rockshaft? Or just that if you lift 300lbs, and then add 300 additional pounds to it by hand, that's okay but the check valves can't hold up more than 600lbs? How much weight is normal these days to be able to lift off the ground on a chain to the rear rockshaft, with a tractor that isn't new anymore?

Thanks everyone.
-David

I didn't say the engine oil/smoke would clear up by itself, just to ignore it for now since it's not the most serious problem.

You shouldn't have to stick your pinky in the touch control and go fishing for oil. It should be full to the level of the hole. If it's not trying to run out the hole when you take out the plug it's low!

Dead lifting 300lbs hanging from the factory rear rockshaft OR 600lbs from the front rockshaft is the same 600 lbs lift for the touch control. Whatever is on the rear rockshaft weighs double to the touch control. Put 10lbs HANGING from the rear rockshaft and the touch control is LIFTING 20lbs.

David:

Would suggest you pay attention to what Scrivet has said to you.

Sticking your pinky in the port to search for Hy-Tran is a CLEAR indication that you are low. Fill it up.

This is the original extension I made for Elllie - TC Fluid was right up to the threads in the elbow.

Okay, point taken
The pinky idea came from Eugene's post here, viewtopic.php?f=1&t=66559&p=543132&hilit=pinky+hydraulic#p543132 and also the touch control manual which says to fill to within 1/2 inch of the filler hole. It did meet that spec, but, I get it, I'll try to add more! I just went and worked the hydraulics, and then was going to try again with a bit more hy-tran, but the fluid had warmed up so that it expanded and DID come out the filler hole when I opened the plug. I'll try again to add more when it's cooled down...

I'm 99% certain this is where I filled the reservoir to when I filled it up, and so I don't think I'm losing any Hy-tran into the crankcase.

So I'm not entirely out of the woods yet, but I a large portion of my issue came from my not quite understanding how the system worked. I did not realize that hydraulic power increases with engine RPM. I figured that as long as the rockshaft load didn't stall the tractor, the pump was turning and trying to lift it, and any further RPM increase wouldn't change anything. I just overlooked trying to increase the throttle, oops.

I took off my 3-pt and put back the factory lift, and hooked up my scale -- one end to the inner hole in the implement rockshaft, and the other end to something heavy. At full throttle the tractor could lift about 400lbs dead lift. That was the only thing attached to the hydraulics -- I disconnected the universal mounting frame.

This is much less worrisome! But still it seems 400lbs isn't great. My thought is that since it seems hydraulic power increases with engine power, and since I assume my watery oil is allowing some power loss inside the engine, it's completely possible that hydraulics will be back up to a normal range once I change the engine oil. That also makes sense with why hydraulic power decreases slightly after the tractor has been running -- engine oil warms up, thins out, and mixes more with condensation, leading to slightly lower engine power.

Sound reasonable, or anything else I should look at? Are there even any TC issues that can cause hydraulics to work moderately well (other than low fluid)? It seems most troubleshooting has to do with things either working, or not working -- I mean, I could pass the TC troubleshooting test, since that only uses 300lbs.

-David

David:

I would suggest browsing the GSS-1024 Touch Control, pay attention to page 5:



I am one of these that use my hydraulics for a lot of unconventional uses not commonly shared by others so I have been learning about the system and it's limitations. One really has to understand them to successfully use implements etc., not specifically designed for a Cub. One must understand the safe operating envelope for the Cub and NOT exceed it or something will break or even worse somebody could get hurt. Safety must be paramount.

I know that a number of folks use a 3 point hitch aftermarket designs on their Cubs. Our own Rick Prentice designed a 3 point hit setup for the Cub but he also stresses pay attention to the weight load and stay within the safe operating envelope of a Cob - and this is from a guy who has not only a 1000 loader on his Cub but a backhoe to boot Have a look at some of the threads in this 3 Point Hitches search.

I would probably counsel a complete oil change including filter element. Probably a good tune up as well to ensure that the C-60 is operating at it's best. Then rerun the test procedures outlined in the 1024.

A maximum load on the Cub's hydraulic system consumes/takes just over two horse power. HP = PSI X GPM divided by (1714 x 0.85). If engine is in good condition, warmed up and the tractor not other wise working/moving you might notice a slight change in engine performance. Engine horsepower is RPM related. Within a range, the faster an engine turns the more horsepower it produces.

Typically an engine will have a bit more power and run better once warmed up. The small minor amount of moisture/condensation emulsified in the engine oil will have no effect on engine performance. Engine performance is primarily dependent on combustion chamber component condition and not engine oil weight.