jcard

This is a trivial thing certainly but I've wanted to modify my 1972 521 to have switches in the door frames to activate the little dome light in the cab. I've seen what appears to be mount points in the door frame for switches but these were never implemented at the factory. Could those used for 510 or 240z cars of the that same time frame be mounted and associated wiring done to accomplish this function? Has anyone done this? if so any tips? I realize that dome or cab light is pretty anemic but would still be nice to have it come on when it's pitch black out. Jerry

That's what I tried, heat turned it all into a sticky mess I was fortunate to be able to clean up. I wouldn't recommend it. I've since fixed the issue. I was able to get some large heat shrink tubing to go around the rubber connector. Turned on defroster and tubing shrunk to fit connector, problem solved. For now.

Thanks I'll take a look. I'm curious that if the defroster inlet tube and the heater outlet tube are the same size why didn't Datsun just run a hose up to it and clamp it in place...why the rubber connector (boot?) was needed. Things to make you go hmmmm?

Does anyone have either a fix they've used successfully or a source or replacement rubber defroster pipe connectors? Some while ago the driver's side coupler split and it along with the flexible tube fell off leaving me with nada defrost capability on that side. Annoying and dangerous on cold winter mornings. I initially tried a initially neat wrap of duct tape around the rubber part. Bad idea. initially worked but in the end in degenerated into a gooey, sticky mess that still fell off. Heat+ duct tape= bad idea. So next idea please. Jerry

I'm interested in this thread since I've worked out most wrinkles in my '72 521 but that poor 4 speed just doesn't cut the mustard on the freeway. Don't like having to make than little engine work overtime to keep up. I'm not interested in the cheapest solution but the strongest most reliable solution to get a 5 speed into the old girl. I'm not going to do the work myself but try to convince my favorite shop to do it. I know that's probably silly but as much as I love driving the old 521 I've just reached a point where I don't like doing major of even less than major work on the truck. I've sort of OD'ed on it after so many years. Still I'd really like a 5-speed in the 521. So what's the optimal conversion. It seemed like it was a 5 speed with mid range gearing, a "dogleg" ( and here I'm not sure of this reference to dogleg) transmission with possible cross member and driveshaft changes. What did I miss? Jerry

I've been reading the replies with interest. I'd love to switch to a greater output alternator if I could. I have a reasonably well equipped machine shop so I could possibly make some different mounting solution but not knowing what to make I will probably stick with an OEM part. Unless I could get both and experiment. Having once had a 1973 240z ( I purchased it new in 1973 and sold it 13 years later with 296k miles on it) I wondered if an alternator from a 1972 240z could work or is out of the question. I can't recall what kind of voltage regulator it had. Jerry

Hi gents. It's been a while since I posted anything regarding my 1972 521 as she's been running great for quite some while. I've some pretty prolific oil leaks from I think the from of the engine which I'd love to fix but probably that's for a later day. The immediate issue is the charging system. I checked the battery terminals and they seem ok, all other connection points appear sound, tight and I've not changed anything in some years. Perhaps 10 years ago I'd replaced the alternator with a rebuild and it seemed to be good. I can't imagine putting more than 3000 miles ( and that's a stretch ) since as I just don't drive her much. Here's what I observe. The truck starts normally and runs well. Normally the ignition light goes out after a few seconds. Occasionally it does not. Most often the ignition light comes on a few minutes after the truck has been running a while. I took a VOM and measured the voltage across the battery terminals before the light popped on and I was getting about 14.5 volts. After the light popped on the reading dropped to somewhat over battery voltage- 12.x. Before this happens I heard loud clicking( nearly a knocking ) from the voltage regulator. I could swear I smell a mild burnt 'something' smell from the engine compartment but very faint and I can't see anything. Both wires to the battery are cool, doesn't exhibit any overheating due to faulty contact. So my question is it the alternator or the voltage regulator that needs attention or both? Jerry

Well it's been some while since I posted a followup to my last post. You know my tale of woe of the angelic 521 that turned into the truck from 'heck... Backfiring from the tail pipe and carb yet I swore there was nothing wrong... Not quite true. Long story short. New Weber carb was loose, two bolts on intake manifold either loose or missing( that last one will take some explanation) Manifold bolts, top rear loose_ish, second bottom front missing- but in my defense very tough to see. These were an easy fix- replaced both with high strength 8 x 1.25mm bolts. Carb was completely dismounted and the adapter/ mounting completely re-seated the way I should have done it in the first place. I reused the OEM throttle arm which fit on the Weber perfectly.. Result? Except for having to fiddle with the throttle cable position - perfect. NO, N-O backfiring or hesitation at any point in the throttle range, hot or cold. I KNEW it could run right...gawd it was aggravating before now...every so often when the old girl is hot I'll get some run-on after shutting her down but I'll get to that. It my further defense- California roads suck. I hate to sink to cheap epithets but it's true. Because we want to be everything to everyone who can spell or point to the word WELFARE our infrastructure, in particular our roads is slowly( and in some cases not so slowly), disintegrating. They are so rough and therefore hard on older cars like this that monthly inspections for loose bolts has been mandatory. This is not the first time the roads here have led to damage, one of the bolts on my 521's steering box snapped and before that the bolts joining the header to the exhaust pipe on a 1990 Miata I had snapped. Now every month I run this little truck here, and I don't drive it a lot and just locally I'll have to check for 'missing things' - which stinks but there it is....These roads basically shake my truck apart... I'm so glad my little truck is running ok, at least for the moment. Jerry

Ah guys... I'm updating this thread as I am essentially at wit's end. I think I've mentioned how my last major change to my '72 521 was to swap out the old Hitachi car for a Weber. It has not run 'right' with it and exhibited much of the same behavior it did with the old(and leaky I found) Hitachi. Backfiring through the carb when cold and often at lugging engine speeds. I've lived with it by gingerly working the throttle up to higher engine speeds where it has seemed happier. This all ended a few weeks back. On the way back home from a routine run over to Orchard Supply to drop off a pair of spent 8 foot florescent tubes for recycling the truck just suddenly started running terribly, back firing through the pipe, wouldn't idle. I nearly didn't make it home. I'm sure I appeared like one of those comedic movies with the guy in his old herky-jerky jalopy sputtering and backfiring down the road. It was awful, I was able to coax the thing into my driveway where it has stood ever since. Attempts to start her have been met with extremely difficult starts and serial carb backfires and no idle at all. It is so frustrating as I only have weekends to work on this thing. The last thing I did this weekend was I pulled the distributor to clean it up, replaced both condensers, and replaced some very old wiring that looked quite bad. I could swear I can see how one set of points was doing anything considering the wire to it was nearly or possibly was broken, couldn't see that fact until I moved it. So I replaced two wires and the condensers. The other thing I tried was to test gas flow from the fuel pump. I put on a length of fuel line to the outlet to the carb, after pulling off the carb line and used a plastic beaker to catch the fuel. I cranked the engine for about 10-15 seconds and got what I'd have to consider is a decent amount of clean, with no visible water, fuel. Next weekend I'm going to dismount the carb and go through every, bolt, screw and hose connection to ensure I didn't bugger something. After that I'm not sure what I'll do. To date I've changed these things: carb( duh) sparkplugs spark wires dist condensers coil fuel filter In the interest of full disclosure I've also done these things: changed to an aluminum radiator replaced smaller hose on fuel tank changed all coolant hoses had heater core rebuilt which I reinstalled installed pioneer 'entertainment system/GPS" ) - made steel brackets to install blow dash installed oil pressure, water temp and tach gauges - plan to install voltage gauge next upholstery - seat redone -black carpet installed So it's not like I'm shy of either doing work or having work done. I really like this old girl but in the last months it has become a drudgery. If only I knew what I was doing Id fix whatever is wrong and be done with it. This little truck had always run well, never any problems It just tootled along very much a pleasure to drive; no sputtering, backfiring never finicky. No she's the truck from Hell.... :-( And all the more frustrating cause I'm sure it's my fault and wouldn't be so if I knew what I was doing! Sorry for the rant.... :blush: Jerry

Interesting experience. The thermostat cover gasket I made failed. I was specific when I asked for gasket material to ask for coolant system compatible material. I ran up the engine early in the morning when it was still cool( 35 degrees) so I could see anything going on. After amount 15 minutes I noticed a very slight cloud of steam around the front of the housing cover which grew to more spectacular proportions after 20 minutes when it actually started gushing. I let everything cool off for a bit, drained enough coolant to clear the thermostat. Long story short, clean parts, implement newer coolant compatible gasket for thermo cover, restart car. No more leak ( thus far ). Very tricky! Jerry

I received the heater core back and reinstalled it and besides no detectable leaks in the cabin the heater seems to better able to keep up with our California winter cold...( and don't say it I know we're wimps out here- but 30 degrees is still 30 degrees) Now next cooling system problem! And I'm sorry this one has me stumped at the moment. I saw this before I started working on the heater core. Something in the engine compartment is spraying coolant! I found it on the air cleaner cover, spattered on the distributor cap, wires, hood. Weird thing is the truck runs with the stock temp gauge just past midway and my newer gauge registering barely 180. I had filled the radiator up to the top after my first test and coolant had a chance to circulate. I must have run the engine for 30 minutes before going for a second test drive and while it sat in my driveway I saw no signs of leaking anywhere so I'm thinking it only must show up under the dynamics of driving somehow. I don't see any signs of leakage from the radiator cap- that area is clean, I don't see any obvious signs of leakage from the thermostat housing. I see no obvious leaks from the inlet/ outlet hoses to the radiator. The hoses to the heater core- are the small 'S' shaped is the original as it seems ok for now and the longer run hose is a length of new hose. I should mention that I installed an new aluminum radiator from Champion Radiators; I see no leaks from it ether. I don't see any signs that it is the water pump. Then there's the fact that it doesn't seem to be severely overheating. the overflow hose from the radiator is running into the overflow tank but I'll double check that hose; there is a small amount of coolant in the tank(not getting sucked back into radiator upon cooling) so I don't believe that's leaking... What the heck is causing coolant to be sprayed has got me. I've obviously got a leak somewhere but where is it! I'll try running the engine for a longer time today in my driveway after filling it back up. to see what happens...

Well my heater core as well as my original radiator( although I doubt it was a real Datsun original radiator) are at the only local radiator fixit shop in my area. Fortunately they seem to have a good reputation and have been in the same location for more than 20 years. They have a can do attitude to that's a positive but the proof will be in the pudding as they say. It seemed once that radiator shops were all over, I guess working with lead as they must make for a tough business. I'll post the results here. Jerry

I think I've got it. There's a small retaining screw. The one on mine was completely covered with black paint; so much so at first look it just appears as a blob of black paint... Jerry

I have an air compressor I'll substitute for me blowing... So how is the valve held in place? Also the foam rubber pieces that sort of held the core in place are a bit sad after all these years, will any high density foam work or is there some that will hold up to the heat better? Jerry

Had some time earlier this afternoon to remove the heater core. The inlet/outlet hoses seemed to be in good condition and pliable. the bottom of the heater box was wet which leads me to believe it was the core itself that had leaked but I'm just not certain I will carefully remove the hoses and see if I could get something newer to work. Even though I see removal wasn't very difficult I don't want to redo this anytime soon. My shutoff valve has not been a problem and works smoothly but I'm assuming I'd have to remove it before I bring the core to a radiator shop? If I read the threads correctly it takes a wood dowel and gentle taping to remove it? What holds it in place?? I'll look for a local shop who might be willing to take on rebuilding this. Jerry