Hey guys,
Had the car up in the air over the weekend and happened to notice that the rear wheels were not turning that freely when I tried to rotate them. I checked the usual things like slack in the hand brake cable, HB lever arm isn't seized and the calipers have just been rebuilt so the pistons and rubbers are fresh. The calipers are R31 and i understand the operation of their internal screw operation which drives the piston outward, but this just doesn't seem right.

I guess my question is; How much stick are other people experiencing with these calipers? Can you turn your rear wheels freely and have them rotate under their own momentum? Mine grab as soon as I stop applying force.

Not a big deal, but just something on my mind.

Tones,
Mine kind of do the same thing. I can hear them grabbing slightly when I rotate the back wheels, and they wont turn on their own. It's not much though.

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1972 Datsun 1600, S14 SR20DET Engineered (204rwkW @ 17psi.)
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#SR20Datsun @SR20Datsun

Interesting. Thanks for the reply Nik. Mine just seems excessive.

The R31 ones are a pain in the ass. I had the same issues on my old r31 wagon.

I haven't gotten around to adjusting the R31 rear rachet system for the handbrake component yet on my 180b, but long term goal is get rid of them in place of a separate handbrake mechanism setup out of the calipers.

Remember that you'd be turning the drive line assembly also.
R31's are a PIG of a calliper. I'm going to go with one of the worst. Its most probably the ratchet for your handbrake.
I had same problem on one side of mine after I had rebuilt it where it was biting and ended up being clamped on to the disk. So much so that a 1km drive resulted in smoke pouring off the disk it was so hot. Not fun. I got the mechanics to do it because it was going there that day anyway.
Unbolt the handbrake. Take the leaver arm off. Use your 10mm spanner or which one it is and unwind the handbrake screw. Then re-install. Slackens off the handbrake itself so that when its dis-engaged the piston rotates back off the disk.

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Ongoing Project: 1972 Datsun 510 S13 SR20Det. http://ozdat.com/forum/viewtopic.php?f=33&t=17898
New Daily: D22 Navara (The new workhorse)
Retired 12/2016: MY98 Subaru Impreza RX
Previous Car: Restored Green 1972 Datsun 510, Hot L18

Have you removed the residual pressure valve from your Brake Master Cylinder for the rear circuit?
The OEM rear drum Master will cause the hydraulic pressure to remain in the line unless it has the valve removed.
And I disagree, the R31 rear calipers are a great unit with the integral E Brake system.
In my opinion anyway

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Regards, Graeme
Just trying to help...
http://nissanman.shutterfly.com/
graemes@internode.on.net

The RP valve was my next thought. I replaced the master a while ago with, what I was told was, a disc/disc master. I inspected the valves and both seemed identical. If in doubt can I just remove the valve from the rear line and elimitate that as a cause.
Can anyone elaborate on the procedure to adjust the caliper?

Yes, I have the Nissan procedure to recondition and adjust the rear caliper.
IMO, the trick is to use lots of rubber grease when assembling the E Brake mechanism.
Send me an email and I'll send you the relevant info.

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Regards, Graeme
Just trying to help...
http://nissanman.shutterfly.com/
graemes@internode.on.net

I have scanned the procedure to my MediaFire site, use this link to download it: -
http://www.mediafire.com/?x1cut1buu1t31

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Regards, Graeme
Just trying to help...
http://nissanman.shutterfly.com/
graemes@internode.on.net

How and where is the residual pressure valve?
I just put an r21 in the rear of my 200b and noticed the calipers sticking on and heating the disc up.Thought the calipers just needed rebuilding but id say I still have the valve in?

What Graham said.^^^^^

The litle one way valve in the base of the M/C meeds to have a small hole, same as the front circuit.