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NP Super Major Clutch

Posted: Thu Nov 29, 2012 5:51 pm
by Fixersteve
Does anyone have any experience doing the Dual Clutch in NP Super Major, Do i need the special alignment tool??

Thanks

Steve

Re: NP Super Major Clutch

Posted: Thu Nov 29, 2012 5:57 pm
by AdrianNPMajor
Sorry can't help with this, Steve. But I have always wanted to know how the dual stage clutch is set up, so I will be learning alongside you! :buddies:

Re: NP Super Major Clutch

Posted: Thu Nov 29, 2012 6:10 pm
by fnoller
Can't help either, but a tool for alignment will properly be a must :D

Throw pictures, they say more than thousand cheers :beer:

Re: NP Super Major Clutch

Posted: Thu Nov 29, 2012 8:18 pm
by liam
To do it properly you do need the jig so that it is set properly . I only fitted a reconditioned unit to my np super a few weeks back .I got it from dunlop tractor parts .I have been told they can no longer be got new. Tractorclutch uk can rebuild them for about 350 pound provided the cover is not cracked and the levers are ok .Hope this helps ,Liam.

Re: NP Super Major Clutch

Posted: Thu Nov 29, 2012 8:48 pm
by janus
http://www.fordsontractorpages.nl/phpbb ... f=9&t=1612

in this topic , you can see self made alignment tool of arno

Re: NP Super Major Clutch

Posted: Thu Nov 29, 2012 9:18 pm
by Fixersteve
Cheers Janus! that link is spot on! Will have an attempt at taking mine apart over the next couple days.

Re: NP Super Major Clutch

Posted: Fri Nov 30, 2012 1:20 am
by halloween
If its any use, my local spannerman managed to get a live drive clutch into my PM and set it up with no special tools :D

Re: NP Super Major Clutch

Posted: Fri Nov 30, 2012 5:57 am
by super6954
halloween wrote:If its any use, my local spannerman managed to get a live drive clutch into my PM and set it up with no special tools :D
Hi I've done some too with out the tools and it's a royal pain in the A#$ :cry: . My new to me at the time Girlfriend when I did the last one. is now an experienced Hand at pushing a Major apart and telling me the heights and trueness of the flywheel and bell housing when pushing the two back together :lol: . I split it 4 times before the pto disengaged properly on dry runs pushing the clutch and turning the Pto shaft by hand :cry: .
Regards Robert

Re: NP Super Major Clutch

Posted: Tue Dec 04, 2012 7:31 pm
by Timeee
Good day Steve

A few years ago, (on looking at my notes, in 2005!) when I rebuilt my NP Super Major, I found a man called Barry Rosewell, who had been Fordson trained and had the Fordson special tools to rebuild and set up the dual clutches. He was also trained in the hydraulic system. He was located near the Yeovilton Fleet Air Arm base at a place called Bridghampton. I don't know if he is still going, but it may be worth a tel call to 01935 840838. If he has long retired, sorry, but he may well know a man who can.... Tootlepip Tim

Re: NP Super Major Clutch

Posted: Fri Dec 14, 2012 9:22 am
by Steven B
I have replaced the plates in three tractors without any issues. I do not have the special tools but I did get, and you will need as a minimum, the transmission input shafts from a scrap tractor. I also had to remove the flywheel as I use it in the setup of the clutch. Here is the procedure I use after splitting the tractor.

Remove the clutch assy and place on bench

Remove the flywheel and lay on bench.

Take photo's and make notes to aid re assembly.

Using a sharp screw driver remove the special cir clips and pins that hold on the release forks. There are six to remove in total. You should be able to work out the six to remove. DO NOT LOSE THESE CLIPS AS YOU CANNOT BUY THEM. Also check for any badly worn pins and order new ones. These are not cheap.

Remove the alloy cover

Use a good valve spring tool to remove the springs.

Separate the drive and clutch plates.

Check all cast iron and alloy parts for cracks. If any are cracked open a bottle of scotch and don't stop drinking until you black out.

Place drive plates and new clutch plates together and install two diagonally opposite springs.

Bolt the partial assembled clutch into the fly wheel and using the input shafts line up the new plates. You will be able to jiggle them into alignment with only two springs.

Remove from flywheel and install the rest of the springs.

Replace the alloy cover and release pins. You will have to crush the cir clips.

Now, bolt the assy back into the fly wheel and re-check the alignment with the input shafts.

Using a vernier calliper, measure the release button hights. There should be 550 to 600 thousands of an inch between the PTO and Main release buttons. You will most likely only have to tweek one or two to get them all level.

Now replace back into tractor. Adjust the clutch pedal. To can test the clutch without starting the tractor as follows. I do this before I finnish the rest of the tractor assembly.

Place the tractor in neutral and high range. Engage the pulley. You will need a helper. Get helper to try and spin the pulley. Depress clutch until pulley spins. Helper now tries to spin the PTO. depress clutch fully and PTO should release.

Assemble the tractor and then start and test.

Good luck.

Re: NP Super Major Clutch

Posted: Fri Dec 14, 2012 1:50 pm
by Dandy Dave
For us old guys that can't see the little numbers on a vernier caliper, the digital readout ones are the cat's tail. This is a little newer than the model that I have. I'm not sure how I lived without one before. You can buy cheeper ones also, but I cannot tell you how accurate the cheep ones are? Dandy Dave!

http://youtu.be/XE_aU1cNJYg

Re: NP Super Major Clutch

Posted: Fri Dec 14, 2012 3:50 pm
by Pavel
Know what you mean, DD -- best thing since sliced bread. Allowed me to get rid of all my micrometers, both imperial and metric.
Here in the bush input shafts are a bit like hens teeth -- especially when you need one like yesterday. I've used a close fit socket on the end of an extension bar to fit into the crankshaft bush and wound insulating tape around the bar to centralise the clutch disc. Needs must when the devil rides!
Pavel

Re: NP Super Major Clutch

Posted: Fri Dec 14, 2012 10:22 pm
by super6954
Hi steven B
I have re built the clutches using a similar method to what you did as regards flywheel and taking it apart and putting it together that's not a problem when you know how, I keep a spare flywheel now to do this so i don't have to take the other one off if not needed too :) .
It can be getting the fingers right. the last clutch I had came from another tractor as good used from under my bench :wink: . I know it was working before I put it in . when it was in the second tractor it would not disengage pto. with the fingers set the same as removal from last tractor. I set them to the removed clutch heights still no go in the end I had them way out compared to the old and new settings for some reason :? . Then it worked perfect and still is :) .
Regards Robert

Re: NP Super Major Clutch

Posted: Sun Dec 16, 2012 1:20 am
by halloween
Steven B wrote:
Check all cast iron and alloy parts for cracks. If any are cracked open a bottle of scotch and don't stop drinking until you black out.
I know that feeling!

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