Jump to content


  • Content Count

  • Joined

  • Last visited

Community Reputation

21 Excellent

About Trnelson

  • Rank
    Active Member


  • Map Location
    Highlands, NC

My Cars

  • Zcars Owned
  • About my Cars
    1971 240z October 1970 build date. It has been slightly modified by PO

Zcar VIN Registry

  • Zcar 1 VIN

Recent Profile Visitors

249 profile views
  1. I know next to nothing about distributors so I can’t fully answer your question. I can tell that the points have been deleted but I honestly have no idea what they were replaced with. Do you think this is something I should try to work with or think about upgrading/replacing all of the components? Maybe cap and rotor for now and run her till she lays down? Thanks for the links, I’ll check them out.
  2. I didn’t readily see any identifying numbers on the coil.
  3. I’ve inherited this electronic ignition system, it was working fine before I tore the engine down and assume it will be ok when I fire it back up. I’d like to find the appropriate cap and rotor for the short term AND know exactly what I have. To this uneducated shade tree mechanic ignition systems are the ultimate form of black voodoo magic. If anyone recognizes these parts please chime in. I’d like to upgrade to the 123 but I think some ZTherapy carbs may predicate the dizzy... short term Please let me know if pics of other parts would be helpful. thanks Tom
  4. The timing set is "Engine Pro" brand. I think it will be fine and I'll chalk it up as a learning experience of what to ask about next time before ordering. I HATE the thought of a master link in the timing chain! While the cam gear didn't have the notches it did have the indents labeled 1,2,3 so I do feel confident that it is properly timed. Just got the Z last summer, I've always liked to tinker with stuff but never really got much past basic maintenance items and bolt on accessories. I finally am in a place in life where I have the means and garage to really tear into an engine. When I was younger the problem was that whatever I was working on I typically had to be able to drive it to work the next day! I'm not a mechanic by trade but I have spent the last 26 years around golf course maintenance equipment, maintaining reel mowers to cut perfectly at .100" is a pretty delicate undertaking. During my first job after college I worked with a great mechanic on taking 8 old Toro mowers and combining them to get 5 of them to operate and function properly. He taught me a lot about laying things out, cleaning up all the parts and how to assemble things. In a nutshell I know just enough to be dangerous but thanks to some great books, this forum and no real deadline for completion I have been able to deal with the challenges that pop up on a project like this. Thanks again for your assistance, I'd like to buy you a beer someday.
  5. It is satisfying to get to the root of an issue, one of the reasons I love this new to me hobby. The only thing more satisfying than having the cam turn freely is having to use a wrench due to all the pressure from the springs and rockers! Had a rain day today and was able to get the top end done, mounted to the block and the timing chain installed. Question, the new timing kit I received, from an unnamed vendor, seems to be of low quality. The chain has a master link, no bright links which makes sense since it is seemingly made to be cut to fit and cam sprocket doesn’t have the “v” notches to set the timing. I had my old chain and was able to lay them out side by side and they are the same length. I counted links between bright links on the old chain and replicated that on the new one. I installed it and it does match up so I feel like it will be fine, I’m just disappointed in that they feel like generic parts. I’m not sure if this is normal due to the age of these cars or if I just don’t know where to shop. Take a look at this pic and see what you think. The top “homemade” bright link is the master link, notice the lack of notches in the sprocket, yes I did check both sides to be sure...
  6. Correct, I was putting the lube on the journals and bearings but when I slid the cam back in I had the same issue with it not wanting to slide all the way in with the tower bolts at full torque. So I loosened everything back up, lubed the journals/bearings, slid it in and when I was torquing everything down the second time is when the Heli-coil broke loose. I finally found a Heli-coil set after 3 stops and decided to check all threads, glad I did because there were two more that appeared sketchy. I’ve replaced them and now have the towers and cam installed. I can easily turn it with my fingers so I’m calling it a success! I’m now beginning to think that the worn out Heli-coil may have been the or at least another issue with the cam fitment. Oh well, either way it’s in and I can finish the top end today. Thanks for the help Captain
  7. Update, I studied the towers more closely and sure enough there was a large burr on the rear most tower. I carefully filed it down flush and checked all the others. You were correct, obviously someone had prayed it off with a screwdriver! I oiled the cam and towers with the bolts torqued to 7 lbs. It still stopped at the fifth tower. I removed the fifth tower and tried to push it into position but it wouldn’t go any farther. It seems the issue was with the front cam journal entering the tower. I loosened all the bolts back up, reinstalled the fifth tower and when it stopped I lightly tapped the top of the first tower and viola, it slipped right in and turned with ease. I incrementally torqued all the bolts down and it spun just as freely as with no torque! I did the happy dance and started laying out the valves for installation. Here’s where it becomes my typical Datsun story... I realized in all my happy dancing that I had forgotten to put assembly lube on the towers, once again I had to repeat the procedure of loosening torquing etc. on the LAST bolt to torque to 25 lbs with about 1/8 of a turn to go it gets real easy and just spins with little to no resistance. WTHis going on. As it turns out those threads had been Heli-coiled. How they didn’t come apart when I chased the threads is beyond me. Oh well, looks like I’ll be making the 1.5 hour round trip to the closest parts house, damnit! Better to find it now than at break-in I suppose.
  8. Thanks for the advice. No screwdrivers were used by me during disassembly but I suppose the PO may have. I’ll check and those items before I make another attempt. I failed to mention that it do I’d spin freely when the cam was in the first 4 towers, it was when I got to the fifth one that things got janky. I’ll start there to see if I’ve overlooked something obvious.
  9. The towers are marked and only finger tightened for the mock up. The wipe marks all looked good but I didn’t check how freely the cam rotated. As far as flatness goes all I have is a 28” straight bar, I can’t remember the tolerances off hand but I did check it with a feeler gauge when I took it apart (Per Monroe manual) and I didn’t have any gaps outside of spec. I’m sure that leaves plenty of room for error but that’s what I had. I will say the engine ran pretty well prior to tear down so I honestly wasn’t looking too hard for parts being bent or out of alignment. Reading that caption makes me think it’s not uncommon, you just have to finesse everything back together. Maybe that’s why the FSM says to not remove them...🤔
  10. Getting ready to assemble my cylinder head this weekend. On a mock up run the cam didn’t turn what I would call freely, I could turn it with one hand but it did require some effort. This quote from “How to modify your Datsun” has me wondering how precisely “striking the tops of towers” is done? I understand the towers are align bored but it sounds like there is some percussive finesse potentially needed to get them back in line. Any tips on the assembly? thanks Tom
  11. On the stripping/cleaning aspect, what is the most efficient way to clean them up in preparation for plating/painting? I did my fuel rail with scotchbright pads and it took FOREVER! I’d like to do something with mine while the engine is out but that level of tedium hurts my head.
  12. I love it when I make a good mistake!! Of course now I will have to take the other second rings back off the pistons and match them up... my OCD hurts sometimes. I was impressed by the quality of the TPR rings, I'm no expert but the material just felt like higher quality than the Wiseco. I'm not sure if you are planning something similar but if you are the process isn't too bad, a bit tedious and time consuming but once you do a few it goes pretty quick. I have about 4 hours invested in the process, 1 of which was spent on the first ring. Just be patient and "sneak" up on the gap your shooting for, I literally would take a measurement and need just one turn of the grinding wheel to get it where I wanted it.
  13. Interestingly the standard sized set was Wiseco and the oversized came from TPR, a Japanese company. I was concerned when I ordered but it looks like it will be fine. Not sure why I didn't think to do it yesterday but I'm going to compare the oil rings from each set to see if there is any noticeable size difference. I'm sure the larger, if it in fact is, would fit, however my concern would be if I just smash it in there if it would hold enough oil being over compressed. Probably overthinking things as usual.
  14. First picture is the standard size on top of the oversized, second pic is vise versa, third is the overlap in the bore prior to grinding and the fourth is halfway through installing the rings. Planning to install them in the block tomorrow, the only concern I have at this point is how the middle oil ring will fit. Thinking it will compress easily but it does seem quite a bit tighter that the one from the standard set. thanks for the input and advice.
  15. Received the oversized rings today, as it turns out they are just a little bit longer. I spent several hours filing each one to each piston and I feel really good about it. I’m now well within tolerance and the overall shape seems fine. The only hiccup I had was not realizing that the lower compression ring is seemingly made of a softer material and I overground one 🤦‍♂️... still a much closer fit than the standard size so I’m sure it will be fine.
  • Create New...

Important Information

By using this site, you agree to our Terms of Use. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.