Case 440 Idle and carb adjustment

What is the idle supposed to be on a Case 440? 650 RPM?

I’m having a tough time adjusting my carb. Seems like the only time I can get it to run “rough” is when I seat the mixture screw. Instructions say to seat and back out 1 turn. Seems to be ineffective once not seated.

What about the power screw? I did the same thing and it seems like it’s useless.

The tractor seems to run very rich. I set the float to 1/4” off of gasket surface.

It seems like it hunts for idle when throttling back to idle from working 1,000 RPM or PTO RPM. At PTO RPM it seemed to hunt for that too.

And gas is puking out of the throttle shaft on the throttle side at a pretty good clip when not running.

So, it makes a HUGE difference when you put the Venturi back in the carb. Just sayin’.

(quoted from post at 12:07:00 05/05/18)
So, it makes a HUGE difference when you put the Venturi back in the carb. Just sayin’.

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es, and it makes a difference if you put it in upside-down, too. Did it quit puking gas? It sounds like the float valve is not shutting off. Another word of warning: make sure you set the float drop, so the float does not rub against the bowl when it's empty. Want to guess how I know about that one?

(quoted from post at 14:28:07 05/05/18)

(quoted from post at 12:07:00 05/05/18)
So, it makes a HUGE difference when you put the Venturi back in the carb. Just sayin’.

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es, and it makes a difference if you put it in upside-down, too. Did it quit puking gas? It sounds like the float valve is not shutting off. Another word of warning: make sure you set the float drop, so the float does not rub against the bowl when it's empty. Want to guess how I know about that one?

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I reinstalled it how it came out originally. I believe it’s right.

I had it purring smooth, but now it is more rough again. It takes a lot of cranking to start it now too. I gapped its plugs to .025 and cleaned them all up. Smells rich.

I set the float level to 1/4” above gasket per the instructions.

What about idle speed? 650 RPM?

I don't have a manual for your 440. My 611B calls for 500. If your carb is a large-bowl M/S I think my manual will cover it, I could scan it and post it here if you want. It says nothing about float drop, though, but you do need to make sure it stops on the stop, not by hitting the bowl, it [u:793399bf05]will[/u:793399bf05] wear a hole in it otherwise.

The float stops by the plunger, not the bowl.

I have a small body Marvel Schebler, TSX936. I appreciate the offer.

There isn't a tang on the back side of the float, that is, on the side of the hinge away from the two float chambers, that keeps it from dropping too far? The large-bowl ones do have.

This is the float I got:
http://www.yesterdaystractors.com/9...mzU-dx9P1KOstaUcBtbPiQJF-hKYyvuIaAqxIEALw_wcB

Just got home. This thing is still leaking gas. It appears to be leaking from every orifice on the top end of the carb. Idle screw, power screw, throttle shaft. Gas in the intake.

I?d replace the carb with a good rebuilt or new carb and be done with it. I hate messing with something that I?m having problems with and
unsure of how to repair. I replaced the carb on my SC after fooling with problems I had with it, best decision I made.
Jim

I pulled it off the tractor again, separated the carb halves and then reinstalled the old float and needle. Slapped it back together and reinstalled it on the tractor. Turned the fuel on and it started to pour out of the intake. I installed the intake tube and it filled up, then started to weep out of the idle adjustment screw.

I set the new float to 1/4" off of the gasket on the top end of the carb and made sure the arms and floats remain parallel with the gasket surface, per spec. The tab comes set to perpendicular to the pivot of the float, such that it doesn't permit the float to go down and hit the inside of the carb. So I don't know why this per spec setting wouldn't work.

Every single time, I checked to ensure the needle seats by blowing through the fuel input.

The only thing I can think of that I did that could be causing an issue... I did adjust the petcock on the fuel strainer under the fuel tank at the beginning of this debacle, when I realized I couldn't shut off the fuel. Could I have increased the volume of fuel such that it overcomes the needle/seat/float action? I still can't turn the fuel off with the petcock, so I'm going to replace the setup.

http://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=ferg&th=74901

How full does the carb get with fuel? I wouldn't expect it to go above the bottom portion of the carb.

Somewhere around half full. Certainly not above the venturi. Either both your floats have holes and are full of gas, unlikely, or something is holding the valve open. Could be a piece of crud, could be the seat isn't tight in its threads, the point got knocked off the needle, don't know, can't see it from here. That valve should shut off the fuel when the bowl is full to the correct level, and it isn't. It works just like a toilet, only there's no handle to jiggle. When you put it together next, make sure you can blow in the inlet when it's right-side-up and not when it's inverted. Not even a little bit. Good idea to replace the fuel shutoff, it's there for a reason. I routinely leave my tractor running and shut off the fuel to drain the bowl, less problems with fuel drying in the bowl and if there's a tiny piece of crud in the needle and seat it'll flush it out when I turn the gas back on.

Just buttoned it back up after a trip to NAPA...

New spark plugs - AC Delco gapped to .025"
New 1/4-turn fuel shutoff valve installed at end of fuel globe
New 5/16" fuel line
New fuel filter

Carb... Not overly impressed with the Marvel Schebler rebuild for the following reasons:

1.) New seat has a hole in the bottom ~2X the original seat (I put the original seat back in)
2.) Power needle doesn't have a gasket and seal that fits. The seal fits, so I fabricated a washer out of brass to act as a gasket so it pushes the seal against the carb body.
3.) Doesn't have a seal for the choke arm.
4.) Main nozzle gasket was slightly too small, such that it didn't fit over the nozzle shoulder it was designed for.
5.) Bunch of gaskets that won't work - probably a universal kit for other carbs.

I carefully put the carb back together using a combination of new and old - old seat, new needle, new float. I tested the float and it doesn't leak. I loose fit the carb halves with everything installed and confirmed there isn't any float rubbing, the needle seats properly and permits fuel passage properly. Turned the fuel on... NO LEAKS!

Now it won't start. I can smell the fuel, so I know it's getting there. I checked the oil and sure enough, gas is definitely in the oil. Now what?[/list]

I forgot to mention, the rear most spark plug was definitely wet with gas.

Shut the fuel off, pull all spark plugs, open throttle and open choke, crank engine until it blows clear air from plug holes. I'm sure it's flooded. reassemble and hope it starts. Did you go to church this morning?

Change oil first?

(quoted from post at 15:21:19 05/06/18)
Change oil first?

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nly if it's really, really diluted or very overfilled. Make sure you've fixed the problem first, so you don't have to do it twice. Just don't work the tractor until you do. You'll want to make final adjustments after the oil change, too.

(quoted from post at 15:36:16 05/06/18)Only if it's really, really diluted or very overfilled. Make sure you've fixed the problem first, so you don't have to do it twice. Just don't work the tractor until you do. You'll want to make final adjustments after the oil change, too.

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The oil is very diluted and the level is reading 3"+ higher than the "FULL" mark on the dipstick.

I pulled the cover and battery. I have the battery on a Battery Minder to bring it back to life. I'm going to grab a new oil filter and change the oil. I don't want to risk damaging the motor.

When I first tried starting it after replacing everything previously listed except the spark plugs today, I got a putt-putt with some grey smoke and that was it for firing. I replaced the plugs, then cleaned the inside of the distributor. Then checked the oil.

You can probably get away with a drain-and-fill, no need for a new filter. Do you have spark? Possible you got something in between the points, a piece of fine sand is plenty to do it.

I haven't checked spark yet because I was concerned that if I spark anything outside of this thing right now, it'll combust. I'm not sure how many gallons of gas I dumped out of the carb and intake this weekend. At least 1 gallon. I'll check it when my battery gets a stronger charge and this airs out a bit.

mechelement, on a project several years ago I had a 300 that had carburetor problems. I rebuilt the original unit, and still couldn't get the tractor to run correctly. So, I exchanged it for a "professionally rebuilt" unit. Same problems. I called the rebuilder, and was told the TSX-635 Marvel Schebler carburetor (which is the same as used on your 440), was a good carburetor, but it hasn't been made for many years, and those still in service have been rebuilt many times. Bottom line he said he had a hard time finding good, serviceable units that functioned well.

In spite of what he told me, I was convinced I could make the unit work if I just kept working with it to get it set right. In total, I tried 3 different rebuilt TSX-635s. All were junk.

Out of frustration about 6 months later I bought a new Zenith 14544 replacement carburetor. Frankly, I wish I wouldn't have waited so long. The new carburetor made the tractor start and run perfectly.

Joe, I've already declared buying one of those Zenith carbs if this doesn't work. I didn't expect to have fuel pouring back into the engine from a carb rebuild. I believe I have the float/needle/seat sorted out now. If this thing won't run right with this rebuild, I'll probably wind up with a Zenith replace-all.

Jason

Does anyone know what the idle RPMs should be on a 1964 Case 440? The only thing I can find is 600 RPMs for the diesel.

(quoted from post at 11:07:56 05/07/18) Does anyone know what the idle RPMs should be on a 1964 Case 440? The only thing I can find is 600 RPMs for the diesel.

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The service manual calls for an idle speed of 600-650 rpm.

(quoted from post at 15:51:50 05/07/18)

(quoted from post at 11:07:56 05/07/18) Does anyone know what the idle RPMs should be on a 1964 Case 440? The only thing I can find is 600 RPMs for the diesel.

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The service manual calls for an idle speed of 600-650 rpm.

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Thanks, Joe. I should probably pick up a service manual for this thing.

No problem.... I just looked at an early 430 Operators Manuel. It calls for the 148 spark ignition engine idle speed to be set at 500 rpm. The service manual I have is a later OEM publication that covers the late 30 series an 70 series tractors. Bottom line is I would set it somewhere between 500 and 650 rpm, where it runs smoothly.

I got it running this morning. The wire that goes into the coil was loose, got it handled and it fired right up. I did change the oil as well.

I can get it running smooth at idle, but when I throttle up, it’s inconsistent. I adjusted the power screw to smooth it out at PTO RPMs. It seems a bit off between PTO and idle though. It hunts.

When they surge that can be a few problems. Running lean can cause that. Or a weak or missing surge spring if it has one. If you can not open up the main jet to the point you get black smoke you may have a clogged carb. No sure what type carb it has so not sure how the main jet it set up

(quoted from post at 12:55:29 05/13/18) When they surge that can be a few problems. Running lean can cause that. Or a weak or missing surge spring if it has one. If you can not open up the main jet to the point you get black smoke you may have a clogged carb. No sure what type carb it has so not sure how the main jet it set up

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Marvel Schebler TSX 936. I’ve greased the entire throttle assembly down really well. In sure which spring is the surge spring.

I’ve found the TSX manual and will attempt to dial this in pursuant to its instructions, which differ from the Steiner rebuild kit’s instructions.

If it has the down pointing main jet adjustment screw that sort of sits at a 45 degree angle if you can unscrew it to the point you can pull it out and have it still run then you have a clogged up bowl vent which can and will cause odd problems. As for the surge spring if it has one it will be on the carb to gov linkage. I do not know that tractor as such but if I could touch it I would probably know what is going on. Sort of hard to trouble shoot things with out being able to touch them LOL

It has an idle adjustment screw and a power adjustment screw. Backing the idle adjustment screw out, it leans it out to the point of stalling. The power screw can be backed all the way out and removed. It just runs very rich like that. The power screw points down into the carb at the back of it.

Just double-checked, but as expected, my manuals are too old, won't cover your carb. Try running the idle screw on the rich side, too lean can cause surging. If it blows black smoke under load, even a little, lean out the main (power) screw. Does your carb have the "economizer" jet in it? It's a small jet that applies manifold vacuum to the float bowl to lean out the mixture at high vacuum (which only occurs at low or no load, when you don't need a rich mix).

You may have to acquire a service manual, not just for this carb but for whatever the next problem is. I recommend it anyway, in fact if you can find all 3 (owner's, parts, service) do it. I was lucky that way, mine came with all 3.

Yep, I made it a little on the rich side and almost all of it went away. It’s idling smooth between 550 and 600 RPM. I saw it needs to be adjusted again after working it, but lightning just struck, so I’m done today.

Thanks for the tips on this!

After replacing the points, distributor cap and rotor, coil, wires and plugs, retuning has been somewhat ongoing. I brush hogged a pasture Saturday and noticed it surging between 600 and 1,100 RPM. I couldn’t get it to stop with normal adjustment, so I reset the power screw to 2 turns out, then bumped the throttle to sit at 1,000 RPM. It smoothed out when I made it richer. It’s smooth at all RPMs now, but it definitely smells a little rich. I believe it’s around 1 flat leaner from stalling out fully rich. It is running so well, I didn’t want to touch it to count flats and jinx myself.

Is it fairly typical to run these this rich?

I don't have to on mine, but it's older and very dialled-in. Did you set the dwell and timing?

(quoted from post at 20:48:08 08/05/18) After replacing the points, distributor cap and rotor, coil, wires and plugs, retuning has been somewhat ongoing. I brush hogged a pasture Saturday and noticed it surging between 600 and 1,100 RPM. I couldn’t get it to stop with normal adjustment, so I reset the power screw to 2 turns out, then bumped the throttle to sit at 1,000 RPM. It smoothed out when I made it richer. It’s smooth at all RPMs now, but it definitely smells a little rich. I believe it’s around 1 flat leaner from stalling out fully rich. It is running so well, I didn’t want to touch it to count flats and jinx myself.

Is it fairly typical to run these this rich?

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Make sure you are using copper core plug wires and not the resistor wires that come in many of the kits.

(quoted from post at 06:01:36 08/06/18) I don't have to on mine, but it's older and very dialled-in. Did you set the dwell and timing?

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I did gap the points to .020" when the lobe pushed the points open to its widest point (45° out). I need to do it again as I believe when I tightened down the points, it pushed the spring arm tighter against the shim a bit. I received my service manual last Friday afternoon, so I haven't had the time to check the timing. I know if I adjust the timing at all, I'll need to adjust the carb again.

Do folks usually put tall stacks on their exhaust on these? It seems like no matter which direction I face the flap, I'm huffing exhaust the entire time I'm on the tractor.

Make sure you are using copper core plug wires and not the resistor wires that come in many of the kits.

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Copper core confirmed... I bought them from Brillman and received confirmation as such prior to placing the order.

(quoted from post at 06:42:03 08/06/18)

(quoted from post at 06:01:36 08/06/18) I don't have to on mine, but it's older and very dialled-in. Did you set the dwell and timing?

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I did gap the points to .020" when the lobe pushed the points open to its widest point (45° out). I need to do it again as I believe when I tightened down the points, it pushed the spring arm tighter against the shim a bit. I received my service manual last Friday afternoon, so I haven't had the time to check the timing. I know if I adjust the timing at all, I'll need to adjust the carb again.

Do folks usually put tall stacks on their exhaust on these? It seems like no matter which direction I face the flap, I'm huffing exhaust the entire time I'm on the tractor.

Make sure you are using copper core plug wires and not the resistor wires that come in many of the kits.

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Copper core confirmed... I bought them from Brillman and received confirmation as such prior to placing the order.

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I would say that the flapper is about eye level on my 611B. No smell

I'd think you'd get more air from the radiator fan, that should way overwhelm the exhaust. Unless you have an exhaust leak in the manifold area, then it'll just pick it up and blow it at you. Flapper valves (raincaps) are usually pointed away from you in hopes of keeping the noise down.

After reading some of the service manual last night, I see multiple issues going on here...

[u:cb521069a9]Carburetor:[/u:cb521069a9]
The service manual differs from the rebuild kit and Marvel Schebler document I found online with regard to setting the power adjustment and air mixture screws. Which is correct?

[u:cb521069a9]Engine Idle Speed:[/u:cb521069a9]
Service manual states between 600 and 650 RPM. Before I was advised to set it etween 500 and 600 RPM. I’m at the low end, I think, as I only used the jumping around needle on the gauge cluster. This needs to be addressed first with a tach meter, I assume?

[u:cb521069a9]Throttle Linkage:[/u:cb521069a9]
Service manual only pertains to the Diesel engine. Is this not pertinent for the gas 148 engine?

[u:cb521069a9]Ignition Timing:[/u:cb521069a9]
Static and Running timing chart within the service manual spicifies two different engine rated speeds, 1750 and 2000, of which the static timing is 5* ATDC and 6* BTC respectively and the running timing is 25* BTDC and 40* BTDC respectively. For some reason, I thought the timing was set at idles speed and 4* BTDC. What is the difference between BTC and BTDC?

So figure out engine speed rating, check static timing first, then running timing? Will an all in one timing light with RPM/dwell/etc. work sufficiently for this or do I need a separate tach meter?

Recheck gap at 0.020”. I don’t have the spring tension tool. How pertinent is this for the points?[/list]

Forgot to mention and this forum never allows post edits... I’m at 4,900 Detroit above sea level. Do I need a smaller jet for my carb?

(quoted from post at 05:54:26 08/07/18) Forgot to mention and this forum never allows post edits... I’m at 4,900 feet above sea level. Do I need a smaller jet for my carb?

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Fixed... was mobile.

(quoted from post at 05:47:57 08/07/18) After reading some of the service manual last night, I see multiple issues going on here...

[u:922eef8518]Carburetor:[/u:922eef8518]
The service manual differs from the rebuild kit and Marvel Schebler document I found online with regard to setting the power adjustment and air mixture screws. Which is correct?

[u:922eef8518]Engine Idle Speed:[/u:922eef8518]
Service manual states between 600 and 650 RPM. Before I was advised to set it etween 500 and 600 RPM. I’m at the low end, I think, as I only used the jumping around needle on the gauge cluster. This needs to be addressed first with a tach meter, I assume?

[u:922eef8518]Throttle Linkage:[/u:922eef8518]
Service manual only pertains to the Diesel engine. Is this not pertinent for the gas 148 engine?

[u:922eef8518]Ignition Timing:[/u:922eef8518]
Static and Running timing chart within the service manual spicifies two different engine rated speeds, 1750 and 2000, of which the static timing is 5* ATDC and 6* BTC respectively and the running timing is 25* BTDC and 40* BTDC respectively. For some reason, I thought the timing was set at idles speed and 4* BTDC. What is the difference between BTC and BTDC?

So figure out engine speed rating, check static timing first, then running timing? Will an all in one timing light with RPM/dwell/etc. work sufficiently for this or do I need a separate tach meter?

Recheck gap at 0.020”. I don’t have the spring tension tool. How pertinent is this for the points?[/list]

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Carb may have been changed. Find your carb model # and go with instructions for that.

Idle speed is not mission-critical. Set as low as you can without roughness or stalling.

Dunno about throttle linkages, maybe one of the Case gurus might? How did you get a manual that doesn't cover your gas engine? But does cover the carb?

I don't understand your timing talk. Are you looking at a chart? Maybe you could scan it and post the pic? No difference between TopCenter and TopDeadCenter. A weak spring on the points may cause a misfire at high rpm, probably not a problem on a motor designed to redline at 2400 or so. But make sure your dwell is spot-on before setting the timing (50 degrees +/- 2 for a 4-cylinder, or read 25 on the 8-cylinder scale). Static timing is fine as long as you check your advance mechanism, turn the rotor by hand and you should feel a light spring at first then a heavier one and it should return smoothly to static rest. If that happens just set the timing static and rest assured it will advance as the rpm rises. There should be a little felt dot under the rotor, put a couple drops of oil on it. May be an oil cup on the side of the distributor also. You can buy a combo timing light/dwell tach if you want or just a cheapie dwell-tach, up to you, either will work. If you set timing with a light, use the static spec at the lowest idle you can manage, then check advance at the given rpm.

Carb may have been changed. Find your carb model # and go with instructions for that.

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Carb is OEM for sure, but I'm not sure about the jet. I verified the OEM carb # with the carb folks out of GA.

Idle speed is not mission-critical. Set as low as you can without roughness or stalling.

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It idles at 500 RPM per the gauge cluster tach. I don't know how accurate it is. Does air/fuel come into play here? I would think it would and if I have the idle set too low and use air/fuel mixture to smooth it out, then it could be running too rich.

Dunno about throttle linkages, maybe one of the Case gurus might? How did you get a manual that doesn't cover your gas engine? But does cover the carb?

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My service manual covers the gas and diesel engines in the 430/470 and 530/570 series tractors. There is one section within the manual that pertains exclusively to the throttle linkages, but only for the diesel engines. IIRC, the linkage that runs along the side of the tractor and hooks to the IP is 7-5/8" long. I was wondering if there's a dimension spec like that on the gas engines, but it would obviously hook to the throttle linkage on the carb and not an IP.

I don't understand your timing talk. Are you looking at a chart? Maybe you could scan it and post the pic? No difference between TopCenter and TopDeadCenter.

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Yes, it's a chart in the service manual and it covers all engines found within the 430/470 and 530/570 series tractors. The Rated Engine Speed RPMs I mentioned are for the 148 cubic inch spark ignition (gas) engine, which is the engine I have in my '64 Case 440. Evidently there are two speed ratings for this engine. The correct (one or the other) speed rating can be found on a data plate on the tractor's engine. I have no clue as I literally found out about this drinking coffee yesterday morning before heading to a meeting. I've never timed a vehicle's engine at a speed rating before. In fact, I've never even heard of this before. I've never used static timing before. I've always timed a vehicle at a specified idle and from what I recall, it's Engine Idle Timing. I've always set the idle to the vehicle specific idle via carburetor adjustment per the idle on an idle meter, timed the engine with a timing light via rotation of the distributor, then check the idle again and the timing again. I've only timed two engines in my life - a 1962 Ford Falcon (learned how to do this when I was 15) and a 1989 Jeep Wrangler (did this when I was 19). I'm 37 now.

A weak spring on the points may cause a misfire at high rpm, probably not a problem on a motor designed to redline at 2400 or so.

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OK, will disregard the spring tension bit.

But make sure your dwell is spot-on before setting the timing (50 degrees +/- 2 for a 4-cylinder, or read 25 on the 8-cylinder scale). Static timing is fine as long as you check your advance mechanism, turn the rotor by hand and you should feel a light spring at first then a heavier one and it should return smoothly to static rest. If that happens just set the timing static and rest assured it will advance as the rpm rises. There should be a little felt dot under the rotor, put a couple drops of oil on it. May be an oil cup on the side of the distributor also. You can buy a combo timing light/dwell tach if you want or just a cheapie dwell-tach, up to you, either will work. If you set timing with a light, use the static spec at the lowest idle you can manage, then check advance at the given rpm.

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I'm lost with: (50 degrees +/- 2 for a 4-cylinder, or read 25 on the 8-cylinder scale). If you're referring to the angle at which the distributor rotates and the points are at its max open point, I would think a 4 cylinder engine would be 45°, a 6 cylinder engine 30° and an 8 cylinder engine 22.5° because it's 360° rotation divided by the number of cylinders. That's strictly at the midpoint of the lobe on the distributor. That's before taking into account the timing advanced or retarded, but that's application specific. ???

I have the side oil cup w/ cap on my distributor.

[u:f27a2fe483]Does this sound right?:[/u:f27a2fe483]
1.) Discover which engine speed rating I have on my engine, either 1,700 RPM or 2,000 RPM, per service manual chart. Remember static timing spec per discovered engine speed rating.
2.) Rotate the crank until it's in the middle of the D|C mark and see where I'm at on the lobe. I believe it should be at the very beginning of the lobe that would fire Cylinder #1.
3.) Rotate the crank until the points are wide open (center of lobe) and reset my gap to 0.020".
4.) Start the engine and let it warm up.
5.) Set the idle, which is either as low as I can set it and have it run or between 600 and 650 RPM per the service manual.
6.) Check the timing with a timing light at the aforementioned idle and adjust it via distributor rotation to the static timing spec which pertains to the engine speed rating on my engine.
7.) Reset idle to previously mentioned idle speed.
8.) Recheck timing.