Jump to content

L20 flywheel


Recommended Posts

I believe that I've got a flat-spot on my 6-bolt flywheel; I've swapped out the starter, thinking that it might have been free-spinning because the shaft didn't kick out, but after swapping it out, I'm pretty sure that the flywheel is the problem.


Has anybody re-rung their flywheel, or do they just grab another one? Are all 6-bolt flywheels the same for Datsuns? 280z flywheel work?

Link to comment
  • Replies 34
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Sorry, they will all interchange and physically bolt up to any L/Z motor. As for clutches, only cars with the matching 200mm clutch/flywheel are the '80-'81 200sx with the Z20E motor (possibly the '82-'83 with the Z22E) and any other L20B powered car. All 620/720 trucks are either 225mm or 240mm.

Link to comment

In the event that I can't find another good flywheel any time soon, is this a reasonable option? Has anybody ever re-rung a flywheel before?




It's the roadster flywheel ring-gear. It seems that it's the minimal approach to getting what I need done. Any clues on what it costs to get a flywheel re-rung?

Link to comment

I have my doubts as to weather the roadster flywheel or starter ring will fit an L or Z flywheel. As far as I know the only thing in common is the 200mm pressure plate and clutch assy.


The old ring can be cut with a saw and removed. To put the new one on, cool the flywheel in the freezer while heating the ring in a 400 degree oven. Quickly place the hot ring over the cold flywheel and tap quickly into place.

Link to comment
  • 3 weeks later...

YOu have a 200 mm 6 bolt from a car. like a 77-79 200sx and any maybe 610s and 710 that had L20 in there.Truck L20s use the bigger 225mm or maybe a 240mm


I believe Napa, Rockauto or maybe others might have new ring gears if you think its bad and a machine shop will put it on. So you can sgtill use you roadster set up or maybe Ted has one in Yelm.

Fidanza has aluminum ones for about 380$

Link to comment

You can replace the ring gear at home. Place the flywheel in the freezer and heat the ring gear in the oven (with your wife's permission) at 350-425 degrees. Quickly slip the hot gear over the cold flywheel and tap into place... easy.


To remove the old damaged one just grind away metal until it splits.

Link to comment

My FSMs all say when working with the flywheel never to drop it. I always thought... Duh. But they never say this about equally heavy parts like the crank or head. Dropping could cause the flywheel to flex like a rubber ball and the ring could pop off.

Link to comment

Based on the way the ring gear sits against the flywheel, there will be no hack-sawing of the old ring gear -- there's no way for the hacksaw to go across the ring gear without cutting into the flywheel itself.


I've read that using a torch and a metal chisel is an alternative solution. I've got a torch. I've got a chisel...



As for a new starter, any thoughts to the value of a reduction gear starter? The stock compression ratio on the L16 is something like 8.6:1. Mine is upwards of 9.58:1. Is that so high that a reduction gear starter is a good option? Or will the stock starter suffice?

Link to comment
All 6 bolt L and Z will interchange but some are different weights. I have seen a 29 and a 21 lb 225mm wheel. Identical otherwise.


sorry to hijack, but thats absolutely true? i can put an Z24 flywheel on an L20? if so then i dont have to worry about gettin the last L series flywheel at the yard.

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

By using this site, you agree to our Terms of Use.