SantaCruz510

After being busy with some home repairs, I'm getting back to taking a look at my 510. I took the diff cover off and confirmed there is indeed a lot of backlash. I also confirmed the diff is a 3.54:1 gear ratio based on the interior markings: H39X11 N7-12 https://i.imgur.com/5pXllmL.mp4 Is this something that can be reshimmed? If so, I may need to send it out to a drivetrain rebuilder.

Hi Mike! RE flywheel: there was definitely no ridges, it was relatively smooth. Unfortunately I didn't take pictures nor remember if there was any glazing or hot spots. I did replace all u-joints on the propeller shaft and output shafts and checked bearings and replaced bad ones on the rear passenger side. I did have one u-joint go in too easy into one of the "ears" of the propeller shaft, I'll double check if there is any slop. Yup, lug bolts are def tight, which it would have been something as simple as this. The diff had actually not been firmly bolted at one point, but thats been taken care off a few months back. You can see the gap there was before: Good point on the shocks, I'll check them out now that the weather is getting better here in the bay area. The coil over springs are def still good. I'll also try and open the diff while its still bolted to the car and see if I can measure the backlash, something similar to this video: It seems that the more the backlash, the worse the clutch chatter. Thanks for the tips!

Hi all, I'm wondering if the amount of slop in the differential propeller shaft input is too much on my 510. https://i.imgur.com/aUJ3A5B.mp4 I have some clutch chatter that I also need to fix - I had replaced the clutch but the chatter remains. I had not resurfaced the flywheel, and maybe there is also grease on the surface as per this thread: The clutch chatter is very audible when partially disengaging the clutch (partially pressing on the clutch pedal) and the engine speed is low - noticeable in any gear. Most of the noise seems to come from the propeller shaft rotational "bounce" due to the slop. https://i.imgur.com/qx2g4Sc.mp4 So I wonder if I have 2 problems, the diff slop and the clutch chatter or if the only problem here is the chatter. Thanks for the help.

Thanks for the tip, I'll confirm the gear ratio this weekend. Hmm, that makes sense, likely what might have caused it then if those half-shafts were never in a high HP machine. I managed to take a few pictures of the diff side, happy to report that end looks fine. I'm only going to have to source those yokes. Thanks for the help.

Also another good point, I'll check if somehow the yokes are being forced into the diff causing part of the wear. As for the wear due to the rotational loading, as you pointed out, must have been due to the previous vehicle they were on. Not sure what vehicle the diff came out of, I have notes saying its an R180 3.545 from a 280z, I'll have to take another look.

Good point, will jack the car up this weekend and check the diff end. Hopefully the diff is in better shape. Its got an L20b hooked up to it with a 5 speed transmission. No idea from where the previous owner got those components. Not much mods are on the car, guessing the HP are still in the low 100HP.

Was changing out the u-joints on the half shafts on my 510 and noticed the wear on the splines that go into the diff. What are your thoughts on the amount of wear? Does it seems excessive and in need of changing out? Also, any ideas from which vehicle these half shafts came from? Thought they were from a 260z, however the sleeve yoke plugs are pressed in place rather than retained with some snap rings as the diagram of the 260z FSM shows. Thank you all!

O'Reilly has them usually in stock at their stores. They keep them behind the counter. Try to get a thicker one although the one on mine was probably bent because the previous owner over tightened it. Also summit racing has them.

That was a good write up! I used it to change out the leaking filler neck on my car and worked out great. I used Spectra Premium FN724 for the filler neck. Had to make some cuts on it so that screws could pass through and bolt up. Before cutting it: After cutting it: Modified the original piece by removing the locking mechanism for the lid: Not sure why I added this gasket, don't think it was needed: Fully Assembled: Later on I added a viton flag so that any drips of gas dont fall directly on the paint, works great

Hi All, was doing a head gasket chain on my 510's L20B and failed to properly retain the chain tensioner and came to find I could not reinstall the camshaft sprocket and to my horror realized the chain tensiner had come out. My mistake was not having inserted the piece of water hose all the way down. Anyhow, after looking at some images and videos online to get an idea of what was going on in there, we were able to get the tensioner reintalled w/o having to take the front cover off. to start off, here is a view of what you are up against To get the tensioner back in you will need a crowbar and a long rod such as the one we fabricated like this: Note that the long rod has a curvature that follows the chain guide, its just not visible here due to the angle of the photo. The shape of the rod helps grab the shaft of the tensioner to allow downward and side to side alignment. The rod should curve to follow the chain guide curvature: In order to get the tensioner back in, you need to push it downwards both on the chain side of the tensior and the spring side of the tensioner. Start of by using a long screwdriver or crowbar - a crowbar works best due to the bend it has. With the crowbar, push the tensioner down and then using the rod push the shaft of the tensioner downwards - you have to be careful here that the rod is grabbing onto the shaft of the tensioner and not on the spring itself. Crowbar inserted: Note the crowbar points towards the tensioner. Rod in position: Without the rod I struggled for a good 45 minutes trying to get it in but with the rod it was an easy 5 minute job. Hopefully this is helpful to others and saves them from having to pull the front cover off.

Thanks Mike I've got a new seal there - will put some grease before installation. Would any of the grooving or pitting on the surface cause oil to leak out? I did have a transmission leak towards the back at the tail end but I don't know if it was from a worn seal, pitted/grooved yoke surface or loose cap on the yoke.

Hi All, Recently got the 5-speed transmission on my 71 510 rebuilt and working on putting it all back together. I noticed a few issues with the slip yoke. When taking the propeller off I noticed a small plate fell off from the slip yoke and later found out its the cover plate for the "vent hole" on the yoke. Is there any venting through the plate or I can I reinstall the plate and seal it shut? I'd prefer not having gear oil leaking through that area. The slip yoke surface that mates with the transmission output seal is worn and pitted, I'm debating if I should replace the slip yoke or put a repair sleeve on there. Napa has NOS 99138 which should be a fit. But at that price it might be better to buy a new slip yoke, zcardepot has part 800-656 however it does not have the dust cover. Thoughts on using this slip yoke w/o the dust cover?