got a new 720, 4x4. clutch problems

1980-1986 Datsun 720 forums. All 720-specific topics and discussion can be found here.
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CT720RAT
Posts: 15
Joined: Fri Dec 10, 2010 7:24 pm
Car: 1983 Nissan 720 2wd King Cab
Location: CT
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Hey guys, i just picked up my second 720, an 85 4x4 longbed. 5 speed for $400!!! shes in GREAt shape and runs like a top, however the clutch feels like its slipping bad, i bought it thinking im gonna install a new clutch. then i noticed the fork has no freeplay and is slamming the slave ALL the way forward (keeping the clutch partially disengaged), i unbolted one bolt on the slave and let it swing crooked a little to allow for a little more forward movement of the clutch fork, and it still feels like its slipping a little, but it definately grabs enough to spin the tires on dry pavement, i think the fork is just not in right. in there anything i can do to verify this without pulling the trans? if i can fix this thing without pulling the transmission it would be great, because if im pulling the transmission, im installing a new clutch no matter what... id like to save myself some money if i can. any ideas?


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breadbox
Posts: 8549
Joined: Tue Oct 17, 2006 4:09 pm
Car: 89 Nissan 240SX
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84 720 4x4KC
Location: Va Bch

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um some say you can adjust the fork if you take out the rubber boot. and just fiddle around. I have not found this to be the case with any of my vehicles.

But It takes me like 3 hours to take out the motor out of my 4x4 alone. and about the same going back. you just need a socket set and a few wrenches and a engine hoist. but to take out the trans sucks because of the transfer case etc.

I know in the case of one of my 240's I forgot to include the clutch fork retaining clip, which when missing allows the fork to move around and possible get stuck or blow out a slave.

I'd personally take out the motor and set the trans and clutch up right. but feel free to try to remove the boot and shift things around. Also I'm not sure if installing a throwout bearing backwards would cause anything like that.

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CT720RAT
Posts: 15
Joined: Fri Dec 10, 2010 7:24 pm
Car: 1983 Nissan 720 2wd King Cab
Location: CT
Contact:

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Ill see if i can wiggle i around, but im not sure how well that will work out. you really think its easier to remove the engine than the trans? in my 2wd it only took about 4 hours total to change the clutch by removing the trans. the 4wd doesnt look too much more difficult is it?

rocky1234
Posts: 17
Joined: Sun Oct 16, 2011 7:22 am

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sounds like inside the firewall ...at the clutch master cylinder ...the adjustment nut does not have free play / or a hydrulic lock plus it maybe to late now (cl disc worn down) ?

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breadbox
Posts: 8549
Joined: Tue Oct 17, 2006 4:09 pm
Car: 89 Nissan 240SX
89 Koop
84 720 4x4KC
Location: Va Bch

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in the case of 4x4, yes easier and less time consuming to take out the motor. weird I know, in 2wd its easier to remove trans just for clutch or replacement or in case of motor work take them out together.

Tips are, remove hood and remove battery first, disconnect main negative grounds from motor or from the truck, drain rad and remove rad, disconnect throttle cable, and unbolt the four small bolts to get the lower motor mounts ( you can do just the single nuts, but putting it back is a b****),unbolt trans, jack up motor lift it slightly pull it forward and keep doing this until its out.


remove the pressure plate and check out the clutch and flywheel for uneven wear, check your clutch fork,slave, and all that works and that the fork is clipped on the pivot and not shifted over, check that the pivot isn't bent. inspect the throwout bearing and spin it and make sure it doesn't bind. This might be a great time to replace your rear main seal... and if you aren't sure how your timing set looks you may want to just check some other things.


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