athoose Posted October 11, 2021 Report Share Posted October 11, 2021 I've not noticed anything wrong with the truck and the battery is 8 years old. That said, I just checked my battery volts when it was running and I am seeing 16.45v. Does this mean the voltage regulator is shot? Thanks! Quote Link to comment
banzai510(hainz) Posted October 11, 2021 Report Share Posted October 11, 2021 (edited) Most likly I get the innova batter alt checket that plugs in the cig lighter as my volt meter put your head lights on, wipers and heater and if you still read over 14volts then the volt reg is shot. it should load down as you turn ON the accessories esp at idle. hopeylly you battery didnt cook all the water out and bulge. only other thing is do you have a Inter reg alt inn a ext reg truck? thwt the only other thing I can think of. I would get a solid state volt reg or a Japan made stock type unit. (japan!!!)60-70$ Parts geek had these I think. I had soem Wells(carquest) solid state that were OK some one said the old ones can be fixed and adjusted but never done it. ther things work and can see if you under or OVERVOLT. many different versions and work very well. every datsun owner should have one https://www.amazon.com/INNOVA-3721-Battery-Charging-Monitor/dp/B000EVWDU0/ref=asc_df_B000EVWDU0?tag=bingshoppinga-20&linkCode=df0&hvadid=80470559180558&hvnetw=o&hvqmt=e&hvbmt=be&hvdev=c&hvlocint=&hvlocphy=&hvtargid=pla-4584070138266025&psc=1 this might be ok. ck the connector end if the same https://www.ebay.com/itm/353410212168?epid=743666015&_trkparms=ispr%3D1&hash=item5248e3e148:g:72oAAOSwFNtgeMHs&amdata=enc%3AAQAGAAACoPYe5NmHp%2B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSd0ReTLyM7cxPnI6zs468EG8XuOWOHFoaLeta1jvB0UTT%2FZ55SJ5nWnig3Jt0Rd%2BFN7xoaxCcVjNfHUa18UmuHNXuAdiFePk6XzUEHYKSmGdTtA%2FOY6kmpW6axAZkRQONvz9oF1a15Xk4nH4rjJC04RLjKZLdkUDi%2BlbbcOfjp6S7dGxUQ6UW5jxE62IqEEpUOeeO%2BphO7nM%2BGYKcqT9cL1QX6LqzqAPWvAgjPBN1IpnrRMPYty65uUxbSDpW2hsoDdGOEXlP0mben7w90%2FMPBNfVf3DhoOGfXiaCW7n%2BJrHGj%2FCw4gwopYVBxyNEi5fPOmP6Y8B%2Bg2bIAGTlY%2FViJdLDuiLHUfhb1m2QEc%2Fx%2Fv%2BLH58vPLnHrTW4fpkxyr%2FCBIfXbdjmdn3AP6MUy9dGGbFgdxw%2BXI0XGDqaOMlG4SNaXer1Feg3zKudk560nsYJV3i%2BrldhVC%2BkMQITe8WaG1rV%2BoFzMLgllxHjTIxe0IZNhM3RXGVGJ7ggrhwyAyOLdomgFyLyfwvwGmWAyQ%2FGCrYCB1Fhw14nSPsEQnYOZdZrZeKcO4ngRwt4b0BTCtZK%2BAJZ6eHiolwMQYVHPsSA1LC2ZsrEd95qz90oRd4S3UtcUlmXb5dG45JWJODsVbI4Ef4fS6n755MDdH2AbYWuI92HhS3xDjL3VAJ1Baz%2FJBTLHppxNwr5yfPzzUbUVowRfkI3pU5%2F91XJsGGpD%2Bfk8D0A1nfldZ6xln4BBR5QVqt0700xCLPV1TA4MNY5GSU40dPGzXv6z19FaPgjcEgDWo6B%2F8KZoqz1yj5r13cGHzXCRH1KYz5QXOMBxJgYOqTnb6Ayd7cMzygrLLrnUNJk6w%3D%3D|ampid%3APL_CLK|clp%3A2334524 Edited October 11, 2021 by banzai510(hainz) Quote Link to comment
banzai510(hainz) Posted October 11, 2021 Report Share Posted October 11, 2021 https://www.ebay.com/itm/164883641804?epid=227978046&hash=item2663d4b5cc:g:~VMAAOSwwQxgrUVA or this one if round connector this is a good brand 1 Quote Link to comment
athoose Posted October 11, 2021 Author Report Share Posted October 11, 2021 Thanks! I'll check it under load tomorrow, see what happens. That battery is due for replacement so i want to get this sorted. At these prices for voltage regulators, if it's fubar, i am thinking i might upgrade to a higher amp alternator that's internally regulated. It's almost the same cost. If i can find one that fits my l16. Quote Link to comment
datzenmike Posted October 12, 2021 Report Share Posted October 12, 2021 The '78 and 79 620 used internal regulators and fit the L series in the 620. Slight increase in output but not much. To convert the older external regulator wiring harness you will need to cut the wires off the old regulator leaving them long and save the plug. Join the these two pair of wires... Yellow & White White/Black stripe & White/Red stripe Plug this back into the harness. Unfortunately, this will permanently wire the choke heater relay ON so find and disconnect the choke heater relay. There are two wires attached to the back of the carburetor. The Blue choke heater wire and the Red idle cut solenoid. They may have a black sheath over them but they are Red and Blue. The choke (BLUE) needs another power supply, so jumper the Blue choke heater wire to the Red idle cut solenoid wire and you are done. Choke power turns on and off with the ignition. 1 Quote Link to comment
athoose Posted October 12, 2021 Author Report Share Posted October 12, 2021 So i checked the volts again. Once warm and at idle, no accessories on it's 15.5, goes up to 16 off idle. Headlights on, pretty much same thing. Adding either wipers or heater fan, 14.5, goes up to 16 off idle. All three, drops it to 13.5, goes up a little off idle. Interestingly, in this situation, the wipers actually go slower in the high speed position. 😂 So is this okay? If i do go with a ir alternator how high can i go on amps before i need to replace the wire with thicker gauge? Quote Link to comment
datzenmike Posted October 12, 2021 Report Share Posted October 12, 2021 I just checked and the 620 alternators, regulated or non regulated L16/L18 and L20B, are 35 amp. There is an optional 38 amp for air con. equipped. So no worries. There are several post on here about an alternator up grade to 50/60 amp from '78 and up cars and the 720 truck but they are a poor fit. Can be done with some work. 1 Quote Link to comment
banzai510(hainz) Posted October 12, 2021 Report Share Posted October 12, 2021 (edited) I say your regulator is bad. the alternator produces a unregulated over volt then the reg is supposed to chop it down to 14.1 or 14.3 to recharge the battery. This is from my experience over the years and its been the regulator. if uncked to could maybe fuck up other stuff. or overcharge the battery and make it burn out the water or buldge. 620s have a small space. So I stayed with the stock alt. I would ck and clean the fuses as hail marry incase soemthing is cont connecting but highly dought it Edited October 12, 2021 by banzai510(hainz) 1 Quote Link to comment
athoose Posted October 13, 2021 Author Report Share Posted October 13, 2021 5 hours ago, banzai510(hainz) said: I say your regulator is bad. the alternator produces a unregulated over volt then the reg is supposed to chop it down to 14.1 or 14.3 to recharge the battery. This is from my experience over the years and its been the regulator. if uncked to could maybe fuck up other stuff. or overcharge the battery and make it burn out the water or buldge. 620s have a small space. So I stayed with the stock alt. I would ck and clean the fuses as hail marry incase soemthing is cont connecting but highly dought it Well if I've got to buy something, I'd rather snag a higher amp alternator and be able to see something at night. Thinking i could take my alternator off and compare it at the parts store. Find one the same size or smaller. There's a 50 and a 60 amp in the z, zx, 720, etc ... Just a few years later. For the moment, i can ride with the lights and fan on and regulate the voltage. 😂 Quote Link to comment
datzenmike Posted October 13, 2021 Report Share Posted October 13, 2021 It's very tight in the 620. Rad hose and the top of the idler arm just below it. The 720 has the idler arm on the outside of the frame rail so lots of room and cars don't have a frame at all. IIRC many swapped in a Saturn alternator? 1 Quote Link to comment
athoose Posted October 14, 2021 Author Report Share Posted October 14, 2021 On 10/12/2021 at 9:36 PM, datzenmike said: It's very tight in the 620. Rad hose and the top of the idler arm just below it. The 720 has the idler arm on the outside of the frame rail so lots of room and cars don't have a frame at all. IIRC many swapped in a Saturn alternator? Think I'll try the Saturn alt. Are 620 and 720 alternator pulleys the same? I need to swap a v pulley to the Saturn but don't have a have 720 pulley on hand (as the swap thread used). Quote Link to comment
datzenmike Posted October 14, 2021 Report Share Posted October 14, 2021 Close enough. I put a '78 620 one on a Dodge K car 90 amp. Also a 710 pulley on a 2002 Altima and a KA24E alternator. Quote Link to comment
athoose Posted October 14, 2021 Author Report Share Posted October 14, 2021 4 hours ago, datzenmike said: Close enough. I put a '78 620 one on a Dodge K car 90 amp. Also a 710 pulley on a 2002 Altima and a KA24E alternator. Great! One finally, question, is the space for the alternator the same for the L16 and L20? Quote Link to comment
datzenmike Posted October 14, 2021 Report Share Posted October 14, 2021 Yes.... for the stock alternator that is. Quote Link to comment
B-rads PL620 Posted October 17, 2021 Report Share Posted October 17, 2021 Hello, I just installed a 50 amp alternator in my 75’ 620, the alternator was a Hitachi LT-150-188, this was basically a plug and play, Only issue was top alt bracket was too short, I used a 7 1/2” x 1/4” turnbuckle with eye ends and a lock nut, also used a 36 1/8” fan belt, nice fit good clearance. Believe it is from a 75 -79 Chevy Luv Truck. I tried a 60 amp alt from a 280z but the clearance was tighter than I liked, it fit but knocked the idle arm on occasions at engine turn off. Sorry no pic’s at this time, I will have to work on that. I was just trying to stop the winkie blinkies at night stopped and turn signals on. It great to have headlights not dimming at idle! 1 Quote Link to comment
athoose Posted October 18, 2021 Author Report Share Posted October 18, 2021 Procured parts for swap at pick and pull yesterday. 02 s series cs121 alt., 10si pulley, alt weatherpack wires. Saturn connector was not wired for the S terminal. Managed to cobble together a good weatherpack connecter with both S and L terminals pulling from a few other GM cars. Took me awhile to find one that even allowed a wire in the S slot. Snapped the head off the first bolt securing the alt bracket to the block. Started looking at the driver's side and it looks like i could mount the alt over there but it puts a corner of the alternator about an inch from the exhaust manifold. Would this create problems for the alternator, being that close to that intense heat? Quote Link to comment
banzai510(hainz) Posted October 18, 2021 Report Share Posted October 18, 2021 (edited) 18 minutes ago, athoose said: Snapped the head off the first bolt securing the alt bracket to the block. OH shit!!!!!!!!!!!!!! I got a puch and tryed to rotate it out counted clock wise wacking on it one reason I stay with the stock set up. those early mounts on the L16 suck for breaking those smaller bolts Edited October 18, 2021 by banzai510(hainz) Quote Link to comment
athoose Posted October 18, 2021 Author Report Share Posted October 18, 2021 (edited) 18 minutes ago, banzai510(hainz) said: OH shit!!!!!!!!!!!!!! I got a puch and tryed to rotate it out counted clock wise wacking on it one reason I stay with the stock set up. those early mounts on the L16 suck for breaking those smaller bolts That's a real tight area! Could go through the gap between the frame and body but the idler arm won't allow a straight shot... And it's a long way out for a drill and bit anyway. I actually broke it several years ago, figured I'd have had the engine out by now. That'd be so much easier! Lol Angle drill! Edited October 18, 2021 by athoose Eureka! Quote Link to comment
banzai510(hainz) Posted October 19, 2021 Report Share Posted October 19, 2021 16 hours ago, athoose said: Angle drill! A guy did this when I broke my engine bolts in my Cherokee. I didnt want to take this on. Yes I had this proplem with my L16 bolts busting all the time in my 510 when it was riding on the bump stops. It was constant. Quote Link to comment
athoose Posted October 19, 2021 Author Report Share Posted October 19, 2021 That slide into place on the l16 bracket like it was factory. No need to remove the bracket. Current belt could free up more space from the idler arm but not needed. Will have to drill the alt holes for larger bracket bolt. Going to wait on not extract until motor is out. VID_20211019_122856615.mp4 Quote Link to comment
datzenmike Posted October 19, 2021 Report Share Posted October 19, 2021 Mine broke off in the '70s because only two mounting points allowing it to try and rotate/vibrate along the axis through the bolt heads. Later L20Bs had three bolts. The most stable structure is a tripod. A friend made a mount and moved it under the distributor on the other side of the engine. Quote Link to comment
athoose Posted October 19, 2021 Author Report Share Posted October 19, 2021 55 minutes ago, datzenmike said: Mine broke off in the '70s ... Technology has improved since then. Zip ties and duct tape for the win! Quote Link to comment
datzenmike Posted October 19, 2021 Report Share Posted October 19, 2021 Maybe could have 'glued' it on. Quote Link to comment
athoose Posted October 22, 2021 Author Report Share Posted October 22, 2021 Where's the auto choke relay located? Anyone have a pic of what it looks like? Thanks! Quote Link to comment
datzenmike Posted October 23, 2021 Report Share Posted October 23, 2021 It's on the passenger inner fender just before the harness enters the cabin. It's about 1" X 1" X 1.5" rounded corner metal box with Yellow, Black, Blue/White and Blue/White wires going to it. 1 Quote Link to comment
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