(quoted from post at 11:48:41 10/27/19) Looking at an 8640 pto is out on it what is the best and worst case on this job.

"pto is out" is a pretty generic/broad term!

If it's just a simple case of PTO clutch failure, that's not too bad, as the clutch pack is accessible by parking the tractor in a sharp right turn and removing the PTO shaft in the hinge area, then the bearing "quill" ahead of it, when gives access to unbolt and remove the PTO clutch pack for repairs.

First thing would be to check the PTO operating pressure at the valve, on the side of the housing, basically down below the driver's left foot.

Worse failures would be the "drop" geartrain ahead of the PTO clutch, or the PTO geartrain behind the hinge point.
 
(quoted from post at 12:11:17 10/27/19) Checked into it further it's the pto clutch..w/o a hands on check.

Well, it shouldn't take more than a couple of hours to get to the PTO clutch and see what's going on.

And then, of course, hopefully figure out why did it fail, abuse, low apply oil pressure etc., so it doesn't happen again.

Also, how much debris is down in the ("dry") sump? Can some be cleaned out? There's a suction screen down there, may need to be cleaned an extra time or two, along with several filter changes.

Good luck, if you get this tractor, it will be interesting to see what you find and what repairs are needed. I hope you post the details!

tE5diYj.jpg
 
(quoted from post at 14:19:36 10/27/19) Any idea on $ amount your
guestimate.

Obviously, price will vary widely depending upon what's tore up.

FWIW, uses 8 lined plates @ some $38 each, and 8 steel plates @ some $31.

Both are available in A&I for about $8 to $15 less each.

Add seals and seal rings, and maybe return spring washers, and it's still not a HUGE number IF nothing else has failed or is tore up.

Good luck!
 
Some times when the High Low fails and blows apart it will damage the PTO clutch hub..if the owner at the tim don't care about PTO use,,it carry's over to the next owner...
 

Which of those models in there with the 30 or 40 series Articulated tractors would twist the chassis and over stress the 619 engine block ?
 
Back in the 1980's the neighbors had a JD 8640 that they were using to run a PTO pump to drain a flooded area. Pump took 300 HP to run, so the 8640 got the task. After a while, the PTO was disengaging, and the operator could not figure out why. So dufus tied the PTO in the engaged position, causing serious damage to the PTO system. Rumor was the hydraulic filters had plugged up, and that was why the PTO was disengaging. Not sure what the bill was on that repair, definitely not cheap.
 
Pretty sure all 8430, 8630, 8440, and 8640 were subject to this issue. There were improvements in the 50 series. Had the operators' read the manual and used some common sense when driving those tractors, this would not have been near the problem some folks had. Beating the tractors across rough ground with the engine wide open pulling heavy draft load didn't help the service life on these tractors.
 
(quoted from post at 20:05:45 10/27/19)
Which of those models in there with the 30 or 40 series Articulated tractors would twist the chassis and over stress the 619 engine block ?

I'm goona call that 90% "rural myth".

Yes, it's true the engine block was used as a structural member to attach the front axle to the rest of the tractor, and there certainly WERE engine failures I don't know if the two were ever conclusively, "beyond a doubt" proven to be related.

Some engines failed at relatively low hours of decent use, and others ran and ran and ran getting the snot beat out of them on road construction, some had big front blades and banged around feedlots, etc., and held up, and so forth.
 
(quoted from post at 01:32:09 10/28/19)
(quoted from post at 20:05:45 10/27/19)
Which of those models in there with the 30 or 40 series Articulated tractors would twist the chassis and over stress the 619 engine block ?

I'm goona call that 90% "rural myth".

Yes, it's true the engine block was used as a structural member to attach the front axle to the rest of the tractor, and there certainly WERE engine failures I don't know if the two were ever conclusively, "beyond a doubt" proven to be related.

Some engines failed at relatively low hours of decent use, and others ran and ran and ran getting the snot beat out of them on road construction, some had big front blades and banged around feedlots, etc., and held up, and so forth.


I have a friend with an 8650 his dad bought new. This poor thing has had a Degelman blade on it forever. Built roads, grub rocks, push anything that gets in his way. This guy is the type that could break an anvil with a rubber hammer. Machinery goes to his place to die, there is nothing of value left when he is done with it. He has not managed to break his block,,,,yet.
 
There are several here with big dozers on that have
never broken as well I?m more inclined to believe a
bunch of Steiger salesman started the rumor so
they could sell their overgrown freightliners
 
They break when they osolate hard against the stops,,It is no Myth,,I have seen it happen many times to both 84's and 86's...the block itself does not break,,the crankshaft does...if you are in flat terrain it is not as likely to happen..
 
I?ve got a Cummins 53 block that almost everyone said never cracked either and there is about 4 around here just like it so if it can happen it usually does to me
 
(quoted from post at 09:57:51 10/27/19)
(quoted from post at 11:48:41 10/27/19) Looking at an 8640 pto is out on it what is the best and worst case on this job.

"pto is out" is a pretty generic/broad term!

If it's just a simple case of PTO clutch failure, that's not too bad, as the clutch pack is accessible by parking the tractor in a sharp right turn and removing the PTO shaft in the hinge area, then the bearing "quill" ahead of it, when gives access to unbolt and remove the PTO clutch pack for repairs.

First thing would be to check the PTO operating pressure at the valve, on the side of the housing, basically down below the driver's left foot.

Worse failures would be the "drop" geartrain ahead of the PTO clutch, or the PTO geartrain behind the hinge point.

Its not that simple One will have to remove the 2 speed planetary and the oil pumps before one could get to the PTO clutch.
Getting the clutch debris out of the bottom of the clutch housing ain't that easy either without splitting the tractor at the engine.

I have an 8640 apart in my shop right now with a failed perma clutch so I know what it takes.
 
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