How do i adjust free play on clutch 0n a 450 john deere dozer

The clutch is not adjustable it is fully hydraulic. That means it is self adjusting, if the clutch pedal engages high on the pedal and the clutch is hard to push you need a new clutch plate and pressure plate.

What do you mean when you say you fixed the cable. It sounds like the cable broke and you replaced it. Is that correct. If so, did you adjust the free play in the clutch pedal to the manufacturers specification. If you have not done this correctly the clutch will either not disengage, or no engage properly. From your description it appears as though there is n free play and hence the clutch is staying disengaged even when you release the clutch pedal. If this is the case, then try lengthening the cable until the clutch pedal moves with say 25 mm of free movement before anything happens, and try again.

Hi Tim:
Sounds like a fun project.
I'd double check:
- the position of the forks in the throwout bearing,
- confirm that the throwout bearing is installed facing the right way,
- confirm that the clutch plate is facing the right way
- check the pivot on the throwout lever, and
- check the clutch pedal linkages.
- Finally, (or first if all the preceding is too basic, Check the adjustment in the linkage to achieve about 1 inch free pedal travel.
My apologies for including what may seem exceedingly obvious items.
Here is a link to a bunch of youtube video clips that may assist you.
https://www.google.ca/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=John+deere+4230+youtube+replace+clutch

Hope this helps.

Bad pressure plate, clutch in backwards, Think of what could go wrong at the time you installed it...

engaging?
you meant dis-engage im sure.
pedal up is engaged,
pedal at floor dis-engages it.
my guess, is the clutch drags unless i push the clutch pedal 100%
to the floor.
1: bad cable is 90% cause. non last this long.
2: no free play is way too loose.
3: broken lever on the pedal top. caused by #1

all fail modes covered here.
http://www.fixkick.com/tranny/clutch/clutch-on-kick.html

If there is no adjustment left on it ,The clutch will have to be replaced.

Adjust your clutch pedal free play (clearance). It should be around 12mm only.

Look at the transmission fluid on a level surface as the vehicle is running . Is the level correct? Now how about the color is it? Is it blackish ? Low level transmission fluid will not allow the vehicle to go in gears correctly. It will engage hard. Now the color dark is the clutch fiber the transmission is out of adjustment and will operate out of range. Now if it slip out going up a hill there is a great demand on the transmission . The band which is a clutch fiber must hold the drum in order to transfer power if it can't the transmission slips and a overhaul will be in order. Just dont overlook the probability,and the simple solution and yes you will definetly need to rebuild the transmission

Clutch adjusted wrong so not fully engaged, or clutch plate worn out.
Pedal should have 1" or so movement before pressure felt building up.
If not, adjust so there is some free play.
If free play is present the clutch itself is likely in trouble or the mechanism is damaged.