Seansm10 Posted March 8, 2015 Report Share Posted March 8, 2015 Searched on my phone here and google with no results.. Trying to stay mechanical speedo in my 75 610, I was directed to pull a sensor out of an 80s Nissan pickup, so went to pickapart found an 81kc, went under and looked a little. Fidgeted a little more... The diagonal shock thing mohnted has stripped nuts so short of cutting it in half that's stuck there, and I can't get my hands between the frame cross brace and trans cross brace to pull the 10mm out and try and pull the sensor Short of cutting an enormous hole in the floor or hacking up everything I see underneath for a 5$ part, are there any ideas filled with engenuity to get it out? Sean 1 Quote Link to comment
datzenmike Posted March 8, 2015 Report Share Posted March 8, 2015 Ah yes the KA swap from a 240sx. These had an electric speed sensor in them that feeds to the ECU or maybe the dash? to be interpreted into a KPH reading on the speedometer. To keep the mechanical cable run speedometer in your 610 you need the speedometer pinion and sleeve assembly from an earlier car or truck. The speed sensor is adjustable for differential and tire size and will work in any vehicle. The earlier speedometer pinions came in a variety of gear sizes to accurately set your KPH. Your 610 goon should have a 3.70 differential and the pinion in your original 4 speeds should have a 17 tooth plastic pinion gear in it. This is what the factory used to match your tire size and differential ratio to your speedometer reading. If you have changed the ratio or are running taller tires than stock, now is the time to say, and the pinion can be calculated to adjust your speedometer error. What you want is a 17 tooth pinion sleeve assembly from a '80-'94 car or truck using a 71B or 71C transmission. Remember, the speedometer pinion gear is matched to the differential, not the transmission. If 17 was in the original 4 speed you will need a 17 tooth in the new FS5W71C from the 240sx. Sounds simple enough but there are pinions from 16 teeth to 22 teeth (or more) Yes a 17 tooth from an earlier 71B 5 speed will work but hard to check every transmission out there for one. How about a pinion assembly from an identical 71C 5 speed? Go to Nissan and ask for # 32702-O3N17. This is for a '91-'93 D-21 Hardbody. After '94 a speed sensor was used in the Hardbody. Just under $30 so cheaper than looking. 1 Quote Link to comment
Seansm10 Posted March 8, 2015 Author Report Share Posted March 8, 2015 Thanks mike. I'd found the mechanical one just underneath the first one I had looked at. It is era specific then in a sense? Out of curiousity I tried the one from my 4speed, but it is far too long. It's halfway out the transmission when the teeth engage.....that's meaningless but anyways... I have a 4.37 centre which I plan to swap in, and as for now I have 175/75 tires it will experiment with when my wheels show up until I can dial in tire size for ideal fitment. Il call that part number in. I didn't see anything on rockauto so I assumed it was a non existant - new part kinda deal. I haven't yet calculated the difference in overall tire height either. Haven't had a moment to touch the datsun in a couple of weeks unfortunately :(. 1 Quote Link to comment
datzenmike Posted March 9, 2015 Report Share Posted March 9, 2015 The difference is 4.374/370 equals 18%. (tire size is much less and can be ignored for now) To go to a 4.375 you will want the speedometer cable to spin about 18% slower so adding more teeth should satisfy this. In theory 17 tooth X 1.18% equals 20.02 or a 20 tooth pinion gear would slow this very close to 18%. You're in luck the '86 2wd VG30 powered D-21Hardbody uses a 20 tooth pinion and sleeve #32702-02G20. 1 Quote Link to comment
Seansm10 Posted March 9, 2015 Author Report Share Posted March 9, 2015 Well you just saved me a few hours of heartache. I was mentally preparing myself for cutting out half the floor pan hahah. I really hope this summer to make some island trips with the wagon on the road. We will have to talk datsun over lunch or somthing with all the help you've provided over pm as well Again really I appreciate it 1 Quote Link to comment
Charlie69 Posted March 12, 2015 Report Share Posted March 12, 2015 Take a 10mm combination wrench a 10mm 1/4: socket set and a pair of channel lock pliers. First leave the cable attached but break the cable retaining nut loose, then snug it back up, remove 10mm bolt and retaining bracket., take channel locks on the nut of the speedo cable and turn to brake loose the pinion drive assembly. Once it is freed up keep turning back and forth while pulling on the speedometer cable until completely out. Remove drive pinion from speedo cable and smile you now have the part you want! Quote Link to comment
datzenmike Posted March 12, 2015 Report Share Posted March 12, 2015 Maybe drain the oil first, or at least not act too surprised. When I had my goon high enough to get at it the oil was in the back half of the transmission. 1 Quote Link to comment
Ed-datsun521 Posted March 13, 2015 Report Share Posted March 13, 2015 http://www.partsfornissans.com/oe-nissan/3270202g20 Samething here but in a 521 I can just buy this and hook it up and it's all gravy !? 1 Quote Link to comment
datzenmike Posted March 13, 2015 Report Share Posted March 13, 2015 Your original 4 speed had a 17 tooth that gave a correct speedometer reading with 4.375 differential and 6.00 X14 tires. So I have to ask what size tires do you have on there right now and do you still have the 4.375 diff? 1 Quote Link to comment
Ed-datsun521 Posted March 13, 2015 Report Share Posted March 13, 2015 Yeah I had 4 speed and same stock rear end With 15" k5 wheels 1 Quote Link to comment
datzenmike Posted March 14, 2015 Report Share Posted March 14, 2015 Your original 4 speed had a 17 tooth that gave a correct speedometer reading with 4.375 differential and 6.00 X14 tires. So I have to ask what size tires do you have on there right now and do you still have the 4.375 diff? Yeah I had 4 speed and same stock rear end With 15" k5 wheels This is not much help. I have 14" rims with 33" tall tires on them. The rim size is meaningless. Speed is relative to tire diameter. I need 215/60R15 ... something like this. Now I can generate a MPH vs. RPMs in 4th and work out your actual speed 1 Quote Link to comment
Ed-datsun521 Posted March 14, 2015 Report Share Posted March 14, 2015 I'm going to have a ka swap 5 speed transmission with the stock rear end Tires are 195-50-r15 Sorry bout that earlyr response 1 Quote Link to comment
datzenmike Posted March 14, 2015 Report Share Posted March 14, 2015 I was cranky after work. 1 Quote Link to comment
Seansm10 Posted June 11, 2015 Author Report Share Posted June 11, 2015 Hey mike so money has turned around for me, finally got around to ordering the pinion with the part number listed for vg hardbody, not even Nissan stocks them anymore. Also tried online vendors to find it's a discontinued part. Do you have one or know where I should be looking next? 1 Quote Link to comment
Stoffregen Motorsports Posted June 14, 2015 Report Share Posted June 14, 2015 Wrecking yard. I use an online database for used parts called http://www.car-part.com/. I can usually find what I need there. 1 Quote Link to comment
Seansm10 Posted June 14, 2015 Author Report Share Posted June 14, 2015 Hey stiff green, I've been through the local yard and there weren't any specific to my needs. Il try that website, thanks!! 1 Quote Link to comment
CWhip Posted June 20, 2015 Report Share Posted June 20, 2015 What part are you looking for? Sorry, I'm confused. The pinion gear itself or the housing? I used the housing from a 83 pickup and took the pinion gear out of the electronic sender from the ka. To remove the pinion just bust the rear of the sender off, it's just full of epoxy and copper wire (a lot of wire!) once you have it removed just drill and slot it to accept the speedo cable. Mated up perfect for me and is reading speed just fine. Checked it per gps and it's right on. Quote Link to comment
Seansm10 Posted June 22, 2015 Author Report Share Posted June 22, 2015 I am looking for the whole unit that goes in the side of my transmission. The one that came out of my 4spd was too long if I am not mistaken Quote Link to comment
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