project nightmare Posted May 19, 2011 Report Share Posted May 19, 2011 Hey guys- New guy here with a 79 620 KC. This is my first Datsun, I bought it as both a daily driver/fuel saver and so I could take my diesel truck off the road for awhile to build some twins for it. However, I grenaded the trans in the Dodge this morning.. now making the Datsun a strong runner is top priority. Onto to the truck.. It's got a Z24 swap with 5 speed (could use some help identifying the trans [i'm pretty sure the shifter was moved back from its original location fwiw]), supposed to have a cam, Weber DGEV 32/36, header, MSD 6AL, electric fuel pump, electric pusher fan and diamond cut sealed beam conversion lights with 9007s(HB5). The body is soso but there is some rust and I did also find some serious rot on the driverside frame rail by the hanger for the leaf spring. I believe its got 3" blocks in the rear with the addition of angle shims. It rides like a wheelbarrow and pulls a bit to the left but the front tires don't appear to be wearing incorrectly. I think the truck started it's life red, was later painted white then the guy I purchased it from did a hack flat black spray bomb job. I'd be willing to try my hand with a pot sprayer down the road. What it needs/known problems- Electrical Wiring help!! left indicator light on dash always on with head/parking lights, no low beams, no dash lights, no water temp, finish wiring tach, put headlights on relays, new ignition lock cylinder, alternator wiring, loose/deserted wires under the hood, general clean up as the PO was not afraid to cut wires!!) Body/interior Window squeegees inside and out. Plans for 4runner outsides, any cheap solution for the inside? New door panel clips,Door hinge pins, vapor barrier, door handle buckets and some kind of sound deadening bucket seats would be nice too Polish wheels Mechanical Bleed Brakes and clutch slave cylinder, figure out why the clutch starts to engage right off the floor Re-weld exhaust, dragged so much it fell off and it wired up in place U-joints tune weber diagnose fuel starvation problem when pulling a hill I am sure I missed lots of stuff but there is a few weekends work of work right there. Maybe say F all that and find a KA and trans from a hard body.. :thumbup: Glad to have found this forum as it has a wealth of information and should be a major asset as I figure this thing out! Quote Link to comment
superharry Posted May 19, 2011 Report Share Posted May 19, 2011 Hey guys- New guy here with a 79 620 KC. This is my first Datsun, I bought it as both a daily driver/fuel saver and so I could take my diesel truck off the road for awhile to build some twins for it. However, I grenaded the trans in the Dodge this morning.. now making the Datsun a strong runner is top priority. Onto to the truck.. It's got a Z24 swap with 5 speed (could use some help identifying the trans [i'm pretty sure the shifter was moved back from its original location fwiw]), supposed to have a cam, Weber DGEV 32/36, header, MSD 6AL, electric fuel pump, electric pusher fan and diamond cut sealed beam conversion lights with 9007s(HB5). The body is soso but there is some rust and I did also find some serious rot on the driverside frame rail by the hanger for the leaf spring. I believe its got 3" blocks in the rear with the addition of angle shims. It rides like a wheelbarrow and pulls a bit to the left but the front tires don't appear to be wearing incorrectly. I think the truck started it's life red, was later painted white then the guy I purchased it from did a hack flat black spray bomb job. I'd be willing to try my hand with a pot sprayer down the road. What it needs/known problems- Electrical Wiring help!! left indicator light on dash always on with head/parking lights, no low beams, no dash lights, no water temp, finish wiring tach, put headlights on relays, new ignition lock cylinder, alternator wiring, loose/deserted wires under the hood, general clean up as the PO was not afraid to cut wires!!) Body/interior Window squeegees inside and out. Plans for 4runner outsides, any cheap solution for the inside? New door panel clips,Door hinge pins, vapor barrier, door handle buckets and some kind of sound deadening bucket seats would be nice too Polish wheels Mechanical Bleed Brakes and clutch slave cylinder, figure out why the clutch starts to engage right off the floor Re-weld exhaust, dragged so much it fell off and it wired up in place U-joints tune weber diagnose fuel starvation problem when pulling a hill I am sure I missed lots of stuff but there is a few weekends work of work right there. Maybe say F all that and find a KA and trans from a hard body.. :thumbup: Glad to have found this forum as it has a wealth of information and should be a major asset as I figure this thing out! Looks cool so far, alot of guys here can give you a hand with yer truck. Quote Link to comment
Siqx20 Posted May 19, 2011 Report Share Posted May 19, 2011 Welcome! Your truck looks like mine did when I first got it! Damn kids and their spray paint :angry: Quote Link to comment
68Datsun510 Posted May 19, 2011 Report Share Posted May 19, 2011 Why is everyone so obsessed with rattle canning their cars black??? Quote Link to comment
wayno Posted May 19, 2011 Report Share Posted May 19, 2011 Why is everyone so obsessed with rattle canning their cars black??? Flat black is the color of choice, it don't show dents even when there are dents. :lol: I forgot, Welcome to Ratsun project nightmare. Quote Link to comment
project nightmare Posted May 19, 2011 Author Report Share Posted May 19, 2011 Update- Dead roadside, definitely battery/alternator related. 2 dead vehicles,2 days. When it rains it pours!!! Quote Link to comment
project nightmare Posted May 20, 2011 Author Report Share Posted May 20, 2011 I tossed a new battery in to get it home after work. Fired right up and ran long enough to get home. I'm going to look into the alternator wiring asap. The factory "T" connector is not there, just spade connectors crimped on the wires. Open to suggestions for how to diagnose this thing. Can anyone tell me if this truck(1979) has the staked/crimped u-joints? Also, as mentioned in my first post, the shifter appears to be moved back and when I lift the boot up, the linkage goes in at the very end of the trans tail shaft. I'm worried about finding the correct u-joints since I have no idea what the transmission is out of. Rock auto lists a precision #391 for both the 620 and 720 trucks. I've also read about the rockford 430-10 as replacements for staked in joints. It doesn't sound like a do at home job.. I appreciate the help, thanks! Quote Link to comment
yello620 Posted May 20, 2011 Report Share Posted May 20, 2011 79 620's should not have the staked u-joints. Should be an easy job. Pics of the motor install? Might help us help you figure out issues. I am curious to see a better picture of those wheels, who made them too? Quote Link to comment
yello620 Posted May 20, 2011 Report Share Posted May 20, 2011 When to much stuff has been hacked on the wiring harness, it is sometimes easier to start with a replacement harness that has not been hacked, However 79 KC are a one year only harness. And i would not even consider installing an aftermarket harness. Quote Link to comment
dedrick Posted May 20, 2011 Report Share Posted May 20, 2011 Welcome! Looking sharp! Quote Link to comment
project nightmare Posted May 21, 2011 Author Report Share Posted May 21, 2011 79 620's should not have the staked u-joints. Should be an easy job. Pics of the motor install? Might help us help you figure out issues. I am curious to see a better picture of those wheels, who made them too? That is exciting news about the u-joints, the staked ones sound like a pain. The wheels are 16" and the thread in style center cap reads MHT. but I don't see the wheel in their current catalog. I'll look into more later as 1 center cap is missing.. Here are some various pictures of the wiring, its partially disassembled as I've been trying to sort the thing out.. Back of the fuse box Additional relay for electric fan. Stuff tied in everywhere though.. Half the wires that leave the plug for the starter are cut. Any idea what the wound up black and blue wires are? I believe that is the fusible link wire with out a fusible link I see there... So the carb has some radial play in the shaft and with out a spring pulling vertically up on the bell crank it won't return to the idle stop. Need to fix the hacked up throttle cable bracket too. Driverside. Abandon ignition wires? Under dash passenger side Base of steering colum Quote Link to comment
620doof Posted May 21, 2011 Report Share Posted May 21, 2011 Damn... The wiring on that thing would have scared me off. GOOD LUCK though! :) Quote Link to comment
project nightmare Posted May 21, 2011 Author Report Share Posted May 21, 2011 Ha, yeah. Officially renamed project buyers remorse. The stuff at the back of the fuse block and the headlights are my biggest concern, the rest of the stuff is stereo/msd/fan/fuel pump related from what I can tell. The temp gauge and oil pressure idiot light would be nice to figure out as well Quote Link to comment
yello620 Posted May 21, 2011 Report Share Posted May 21, 2011 With a harness mess like that, i would certainly be considering starting over with an uncut factory harness unless wiring is easy for you. Then add the electric fan, headlight relays, and whatever else you might need for the z24. For that matter, replace harness and install a KA24, rewire everything. Done. Quote Link to comment
project nightmare Posted May 21, 2011 Author Report Share Posted May 21, 2011 I'm really not much of a wiring guy but it will be a good opportunity to learn something. They don't get any less complicated than these trucks at least. So the wires into the fuse box are figured out... There are 2 wires used on the switched side of the box, one for the 86 pin on the fan relay and the other for the head unit. There is 1 wire used on the constant side for the head unit constant. Now I'm not a huge fan of scotch lock connectors but they could have at least used those as opposed to cutting the wires 2 inches out of the box and using a butt connector with the factory wire in one side and the factory wire + the additional wire in the other :blink: I ran out of light before getting to the stuff on the steering column. If I can restore everything under the dash to stock form everything under the hood should be a breeze (fingers crossed). Now taking donations for a KA haha Quote Link to comment
yello620 Posted May 21, 2011 Report Share Posted May 21, 2011 Are you aware of the wiring diaghrams for Datsun trucks online?? www.olddatsuns.com Has every year 620 diaghram. That site own owned by a Ratsun member(mklotz70). Quote Link to comment
pharouh Posted May 21, 2011 Report Share Posted May 21, 2011 I feel your pain about the wiring. I had to take mine out and trace everything using wiring schematics and a FSM.P.O.'s love to cut and run new wires instead of fixing the problem. Good luck! Quote Link to comment
project nightmare Posted May 21, 2011 Author Report Share Posted May 21, 2011 FSM POs? I ordered a used Haynes manual off amazon for 50 cents but did also stumble across the diagrams on olddatsuns. Blew those suckers up to 200% and got after it! Quote Link to comment
project nightmare Posted May 22, 2011 Author Report Share Posted May 22, 2011 Well, I spent the better part of the day working on the truck and made a tiny little bit of progress... Got the new u-joints in but it was a battle from start to finish. Starting with the discovery of only about 1/8" of forward travel for the slip yoke! I guess the truck is so low combined with the bullshit drive shaft someone installed the slip yoke runs right into the tailshaft housing of the trans. With compression of the rear suspension the shackles should move the rearend away, its the rebound I'm worried about. 1/8" was not enough for the pinon yoke pilot to clear the pinion shaft/nut so that was a pain as was going back in. I'd rather ride it out and forward the cost of shortening the driveshaft towards a KA. Next, there were NO bolts through the trans cross member into the trans mount:blink: As for the u joint themselves, it took a press, a grinder and heat to complete. Later I replaced a suspect fuel line coming from the tank to the electric pump on the frame rail. Probably wasted $6 of fuel on the ground (prices these days :P) fighting the siphon or head pressure or whatever caused fuel to pour endlessly out of the draw tube. Rookie move haha Next time a friend has a "good running" for cheap, I'll think twice. Quote Link to comment
Wide14u Posted May 23, 2011 Report Share Posted May 23, 2011 is that a z20 motor in it looks like my z24 but half the plugs Quote Link to comment
project nightmare Posted May 25, 2011 Author Report Share Posted May 25, 2011 I swear its never ends!! The charging situation has been resolved with a 1/2" shorter belt of the proper width. The alternator was slipping quietly so to speak and was covered with black rubber dust to prove it. I drove the truck to work today and although its a little better over all with the new u-joints and trans bolted down its still safe to say the driveshaft is way out of balance. Or maybe a potential pinion angle problem, either way it shakes like a bitch anywhere above 45. 6 Blocks from home the truck died and refused to start. It would fire then die and the starter was cranking strong the whole time. Having just put fuel in the truck the day of purchase, I figured there was no way I ran it dry but since the electric fuel pump changed tone I pushed it off to the side of the road and went for gas. To my surprise, it only took 3 gallons of fuel before it started running out of the filler neck...Then it fired right up. So what gives? Is a broken or cracked pickup tube common in these trucks? As for the electrical, the fuse box has been returned to its original state after some serious out of position soldering, haha. The PO really didn't leave me much to work with coming out of the fuse box. Next problem is no dash lights or low beams. The plug under the passenger side dash got real hot at some point and burnt a few pins. Those pins have been bypassed with new sections of wire but its all pretty suspect. All head light wires test good to that point and the high beams/passing will light both head lights on the passenger and one on the driver. Hopefully it has something to do with the dash lights as well. A project for another day Quote Link to comment
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