JD A Vibration

[Super 77 puller]

I bought a JD A with a spun rod bearing, so i never ran it much i ran it from my trailer to my shed. So i found another tractor that was in pretty sad shape, pulled the crank out of it, had it turned on the rods, put new bearings in it. and put it all back together. well it runs ok, its hard to start, and has a bad vibration. Im not sure if its what i did or if its something that im overlooking. If you turn the fan back and forth it seems to have alot of "play" like real bad gear lash in that unit on top. Has anyone ran into this before? and what could be causing the vibration?

 

[Mike M]

The fylwheel and/or clutch driver on in the wrong spot usually causes them to vibrate.

 

[Christopher S.]

On the Clutch Driver there will be two little arrows stamped into the metal. Line these up, other wise there will be a lot of vibration.

 

[johndeereman]

fanshaft wont cause vibration but get it fixed i let the ones go in my b come to find out that the gov.bearings were shot too ended up puttin the fan right through the radiator while i was tryin to pull start a 4020 with a tmr mixer hooked to it got it started but was costly for me

 

[Anonymous-0]

i bought a jd b and it shook like a harley. i unbolted the clutch driver bolt to see it was not inline. lined it up and smooth as a sewing machine. LH

 

[Anonymous-0]

I've got a JD-B that vibrates also after we had it worked on. I'm not a mechanic, so please explain where the clutch drive bolt is located and how do you set it. A pic would really be helpful.

 

[Mike M]

Pop off the clutch pulley tin cover and in the center of the clutch you will see the clutch driver bolt that holds it to the crankshaft it has a large washer on it too. Take this bolt out and then you can see the splines and you should be able to see a V mark on the crank and one on the driver hub. Make sure they are lined up next to each other.Like this >< When you go to tighten that bolt if you don't have someone holding the fylwheel still take a mallet and beat on the outer end of your wrench in the tightening direction this acts like an impact so you can get the bolt tight as the crank wants to turn on you.

 

[F-I-T]

The previous posters already told you that both the flywheel wheel and the clutch driver have off-center weights to counteract the crank throws. There should be "V" marks on both, but I think, if memory serves, that the flywheel weights side sits opposite of the crank throw on #1, so that when #1 is at top dead center, the flywheel weight will be directly aft, 180*. The clutch driver weighted side should sit opposite of the flywheel weight. Others can jump in here if that is not correct, and it is certainly easier to discern if you are looking at the tractor when describing it.

On the fan shaft, you can search the archives and get a lot of useful information on the diagnosis and setting of that twin bevel gear set. I know that I have posted on several threads that covered this repair/adjustment. It is best attempted with the governor case and fanshaft off the tractor, holding the case in a large vise, and then setting by shims, the gear heel and lash. Read about it before you dive in. It's a decent thumbnail estimate to rattle a fan blade and try to guess at the total clearance, but you'll only ever get it "right" on the bench. Too loose is better than too tight, but a lot depends on the condition of the gears, and you cannot always go by just the play.

HTH

Frank

 

[Anonymous-0]

Mike M, That is the information I needed. Thanks

 

[Super 77 puller]

Problam solved, clutch driver was not in the right spot, thanks for all the info