The Fordson Tractor Pages Forum

I have adjusted the clutch pedal to travel 1.5" before engaging and installed a stop pin in the clutch pedal bracket. When I push the clutch to the pin, the gearbox isn't fully disengaged (the gears crunch a bit when shifting). However, the clutch pedal must be almost completely released before the tractor starts to move. This makes it almost impossible to slowly "slip" the clutch to move the tractor. Does this sound like the clutch plate material is almost gone? When hooked on to a bush I tried to remove, the tires would spin on the concrete, so the clutch material must be sufficient for that. Any suggestions? Thanks.
Marlin

Sounds like your pilot bearing is bad, try it without the stop pin in the upper hole (the one you've had it in) and see if the problem persists, if it does the pilot bearing will need replacing, if it doesn't the clutch is out of adjustment or worn, either way you'll need to split the bell housing to sort it.
Sandy

Removing the pin & depressing pedal further solves the gear meshing issue so I'm left with replacing the clutch. I don't find any clutch fixtures available in the States. I do see some "clutch assemblies" for sale. This is significantly more money, but would that be better than trying to replace clutch disk without fixture? Thanks.
Marlin

Look at the repair manual section on the dual clutch first, then see what tools you might be able to get around and the ones you can't you can try and make to allow the repair to be done without trouble. To align the friction plates you can use the input shafts.
Manual here:
http://www.fordson.se/4A_Koppling_Suple ... 01-016.pdf
Sandy

I split the FSMD to look at the dual clutch. All springs & levers appear intact and I don't see any obvious mis-adjustment issues with the lever screws. About 8oz of oil drained from the bell housing when I pulled the bottom bolt and the clutch assembly has a light coating of oil on it. The one clutch disk that I can visualize, seems to have plenty of material on it. Will that amount of oil contaminate the disk friction material and cause excess slippage until the pressure plate is fully engaged? I haven't run any equipment on the PTO, but the transmission clutch disk doesn't gradually engage when releasing the clutch pedal as with my other tractors. I only have a very short distance at the top of pedal travel from initial engagement to full engagement (approx. 1-1/2" free travel when clutch pedal released). After full engagement, there isn't any slippage that I can detect. Any help is appreciated. Thanks.
Marlin

Hi Marlin, there should be no oil in the bell housing, and if it has contaminated the friction plates they will need replacing, it would explain why the clutch takes alot of travel before it bites. There are 2 ways for oil to get in there, rear crank seal or gearbox shaft seal. There is a hole in the bottom of the sump part of the bell housing to allow any leaking oil to drain before it can build up and get anywhere near the clutch which should have a 'jiggle' pin in it (a loose split pin) to stop it blocking. Sounds like that hole has become blocked and the oil has built up and got on to the clutch. You need to find the source of the oil leak before you rebuild anything, and sounds as though you may need a new clutch, or at least friction plates. You will need to do as Sandy says and study your options and costs before deciding which way to go
John

If you undo the ring of bolts arond the outside of the clutch the whole clutch pack will come away from the flywheel in one piece (its heavy!!) then you can remove the flywheel (also heavy) and see if the rear crank seal is leaking. But before you remove the flywheel make a note of its position on the crank, some will only fit in one place but others will go 180° out making pump timing impossible as there are timing marks on the flywheel
John

Before you remove anything see what colour the oil is, black is from the rear crank seal (a big job, you'll need to remove the crank from the engine), brown is from the gearbox, and it sounds like a gasket quite low down. If the split pin is not there regularly check the hole isn't blocked, to avoid getting a puddle, if it is there check it moves about freely for the same purpose. As for the clutch you'll need new linings and a good clean to remove all oil from it, the approximate clearances should be ok but see if the clutch works properly when you reassemble it. The pedal free play should be 1 1/2" to 2".
Sandy

The weep hole in the bottom of the sump casting was plugged. I removed the clutch assembly and the front disk was crumbling. Agriline says the new clutch assembly is out of stock. I haven't found any suppliers of clutch assembly in the USA. I can buy the disks, but cannot find a dealer or former mechanic that has setup fixture. My next step is to dis-assemble the clutch and replace disks. Any suggestions on how to center the disks in the assembly, and adjust pressure plates?

Here are the approximate measurements, remove the flywheel and use it as a base, and use the input shafts to centre the plates (you can make tools but this works well if you don't have that option). Keep the manual handy too. The special tool was rare in those days, so there will only be a handful worldwide now.

Sandy

With the introduction of the NP Super Major slightly thicker transmission and PTO plates were used, and when replacing these plates in a clutch care must be taken to ensure that the plates are a matched pair, in other words the plates must both be the earlier thinner type or they must both be the later thicker type. If they are not matched it will be impossible to set the clutch up properly.

The setting tool remained unchanged for this.
Sandy

I'm trying to disassemble the clutch and having difficulty removing the spring pins on the PTO levers. I've removed the circlips and tapped on the pin with a brass punch & small hammer but they don't budge. I've tried tapping from both ends to try & free them but they still don't move. Am I missing something or should I be more aggressive? Thanks.
Marlin

Try moving the levers a bit and seeing if you can get the pins to turn separately, then try to remove them as it should be easier. Try and avoid letting the springs ping out and get lost.
Sandy

The pin's shoulder has serrations so pressure with a pair of pipe pliers popped them out. I managed to not loose any springs (yet).
Marlin

After cleaning up the clutch surfaces, I see some fine cracks (like fish scales) in the transmission clutch pressure plate surface. Do these need to be machined out? If so, is this something a general automotive machine shop can do?
Marlin

The cracks are caused from overheating, usually a slipping clutch. It's one of those things where some will tell you it's nothing to worry about but personally i would get the plate assesed at a machine shop. It depends on how deep the cracks are, but also if the plate has been subjected to alot of heat it could have warped and will need checking for any distortion. It may well be fine, but for the time and effort of rebuilding the clutch pack it's better to be safe than sorry. Sandy may be able to give you the minimum thickness for the pressure plate so you will know whether it can be machined if it needs it
John

These will have been caused by the heat generated as the clutch slips on engagement. If the pressure plate is not scored or the surface does not look warped or twisted I would leave well alone, just clean the surface up with some very fine emery cloth or wet and dry and WD40 or similar. Apart from anything else if you continue to spend more money you may as well just go for broke and fit a complete new clutch assembly. I will have a look at the workshop manual to see if there are any guidelines on re-facing the pressure plate.

There's no suggestion on resurfacing the pressure plate in the Ford manual.
Sandy

Well if there is no detail in the manual, Sandy, that means Mr Ford says don't do it! Re-facing clutch pressure plates is not generally advisable for most applications. It can sometimes be the case that buying bits such as the driven plates, thrust bearing, toggle fingers etc separately can come to more than buying a complete clutch kit, that is something to be mindful of.

The flywheel has the bronze pilot bushing. Should I replace this with a new ball bearing pilot bearing or leave the bronze one where it is? Thanks.
Marlin

Hi,

When I was in there some years ago I was in doubt as wel. The bearing was cheap and I wanted to be sure. So I changed it.

Afterwards I thought what could have gone wrong with the old one. Not much I think. It can’t get blocked like a ball bearing can.

Can you measure the hole and compare this to the shaft size?

The bronze bearing is regarded as very good, keep it if it's a good fit. Ensure it's well lubricated.
Sandy

I made spacers according to the diagram (0.575" & 0.597") and have compressed the release levers of the transmission & PTO pressure plates but still cannot obtain the clearance required to insert the spacers. The PTO levers are completely down to the clutch cover and the clearance is not nearly 0.597". I can probably extend the adjustment screws to obtain the necessary transmission pressure plate clearance, but they would be at their maximum length. I can see daylight between the transmission clutch plate and center drive plate and it measures 0.125". I can see daylight between the PTO clutch plate and the pressure plate, but it's much less, probably in the 0.04" range. I'm using the flywheel as a base with enough spacers between it and the drive plate to allow the clutch spacer to be inserted and using a 25mm bolt through the center with a disk & nut to compress the release levers. Am I doing something wrong? Thanks.
Marlin

By the way, I'm reading the " (double quote sign) as inches since I'm in the USA. If this is incorrect, please let me know.