Flywheel replacement

1980-1986 Datsun 720 forums. All 720-specific topics and discussion can be found here.
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Nails
Posts: 2
Joined: Wed Jul 07, 2010 4:28 pm
Car: 1985 Nissan 720 King cab
Location: Vancouver Island

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Hello, and am I ever happy to find this site!

I own a 1985 Nissan Z24 with 455K+ kilometers on her. Still has a lot of poop and I've grown accustomed to the old gal. We've been through a lot together.

A few months ago the starter started acting up. Made the sound of the Bendix not engaging.
Being a 5sp manual transmission, I Just just put my foot out and wiggled her back and forth a few times and she'd fire up.
This worked up until a few days ago and then it made an awful grinding noise after it started.
After I made it home that night, I pulled the starter and looked at the flywheel and the teeth had been badly damaged.

Being a bit of a DIY type guy, I decided to tackle the task of replacing the flywheel in my garage.
I've sent quite a few hours searching online for step by step instructions and I've done pretty well.....so far :crazy:

I dropped the drive shaft behind the flexible "yoke" (not sure if that's the right name for it). There is still a short drive shaft that goes through the "yoke" and into the gearbox.
I have wound out all mounting bolts, disconnected speedo, clutch linkage, wiring, and all else that looks as if it needs to be undone.

Now, the transmission is up on jacks underneath the truck and I'm wondering how I'm going to get the short part of the drive shaft that comes out of the gearbox out of that "yoke".
There are mounting bolts that hold that "yoke" on but I'm not sure if I have to take that off.
I tend to be a guy that takes more apart than needs to be so, I figured I'd ask a few of you guys that may have had experience of this sort.

To be honest, I'm a journeyman carpenter by trade so auto mechanics is not my expertise. Mind you, I have turned many a wrench in my 51 years of being on this planet so I'm not a complete dunce in this sort of thing. When it comes to building, I have that beat. When it come to fixing vehicles, I'm never ashamed to ask for help. :)


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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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Aww wtf?! I typed a response and clicked submit and it opened the full editor blank and it didn't submit.

Anywhooo.

Is your truck 2WD or 4x4?

4x4= Leave trans there and remove motor to replace clutch/flywheel

2WD= Leave motor drop trans to replace clutch/flywheel

User avatar
Nails
Posts: 2
Joined: Wed Jul 07, 2010 4:28 pm
Car: 1985 Nissan 720 King cab
Location: Vancouver Island

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It's 2WD and I'm glad you suggested to drop the trans and not pull the motor.

I'm 99% of the way there already...

User avatar
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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Its easy if you have and extra set of hands around to help pull the motor and get it back.

noface
Posts: 99
Joined: Thu Mar 11, 2010 2:25 pm
Car: 1985 Nissan 720 4x4 King Cab

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my truck is 4x4, and I've nevere worked on one of these that's 2wd, but what you are describing is called a carrier bearing. Sounds to me like you have a two piece drive shaft. One short shaft coming out of the transmission, where it connects to a second, longer shaft that then connects the differential.

The carrier bearing should be removable from the frame. Undo the bolts/mount that connect it to the frame, and then slide out the short shaft from the transmission as one "unit". Then you drop the transmission and replace clutch/pressure plate/flywheel...


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