metalmonkey47

I would investigate a little further before attempting to pull it. When I bought my car from the PO, it still had factory looking braided hoses on the heater core and heater valve. The hoses were cut off at the firewall and the heater was bypassed. Although the hoses looked okay from the outside, I obviously still cut em out and replaced them. When I pulled it all apart I found that the heater valve was corroded and nasty. I assumed that's where the leak originated that had them cutting the heater hoses. I'm not one to throw out possibly good parts without testing them, so I cleaned it up with some steel wool until it looked presentable again, ordered some hoses from MSA, and finally put it all back together last night, expecting the 40 year old core to leak, or the valve to spray, but after running 30 minutes at temp not a sign of the slightest leak. I guess what I'm trying to get at, is be sure that's your issue before ripping it apart. You can buy UV dyes, rent radiator pressure testers (P/N 9300 at Autozone iirc) that will help you verify your leak before gutting the car to get to the core. I'm 23 and I was NOT looking forward to pulling my heater core out... Thankfully I didn't have to...yet. Datsun trucks are far easier then the cars.

Sorry for the delays guys, and thanks for the suggestions. I got my copy of Just SU's so I've been trying to find time to watch that before trying to fry my brain. The car still runs rich, even AFTER going through needles, centering nozzles, etc etc. I'm only getting about 110 miles to a tank. Yikes. I figure this HAS to be related to float height, i have a verified 3PSI @ the carbs and there is no trash in the needle and seat. I'm about 3 turns down and if I'm anywhere above that, the car refuses to run properly at operating temp below 50 degrees. I want to make sure I'm understanding how float height 'should' be set. You would want the fuel level in the nozzle to settle right at the tip of the nozzle with the adjustment set for driving correct? So if 2 1/2 turns down, the fuel level in the nozzle would be around the tip of the nozzle? Or would you want it slightly below the tip of the nozzle since the needle displaces a small amount of fuel when fully down?

Bump! I'll go through my garage and see what I have that I don't need. I'm sure I have a lot! Rossiz, pm coming your way!

So just a little back story on the car: It's a bone stock L24 with L28 N47 head (E31 is getting some special work done) and because of the N47, a low pressure electric pump and regulator set at 3PSI. Over the last few weeks I've noticed when starting my car cold it seems to start very hard without opening the throttle a tad bit or revving the snot out of it. For a few moments after it starts. The car seems to be running WAY rich all of the sudden, at about 2 turns down. Today it didn't want to run very well leaving work on my lunch break, and was quick to stutter and choke. You could smell the raw fuel. I've been having issues with my SU's running rich for a while and I haven't been able to rectify this, it seems to be getting worse, and now I'm just getting frustrated. I've already: -Checked needle height - they are flush with the piston about 1mm down or so, followed all of the interwebz rebuild guides -Pistons move freely and are dropping fully -Chokes are shutting off fully and the nozzles are up all of the way -Float is set properly, using the clear hose trick to measure the fuel level in the bowl The carbs were recently rebuilt by yours truly, which was a learning experience all in itself. I LOVE the simplicity of these carbs but now this problem is starting to drive me crazy. It's getting worse and worse and I can't stand it anymore. Plus, 14mpg sucks!!! It almost makes me wonder now that i think about it, if one of the new needles is stuck or dirty, and one of the carbs is flooding or spilling over when the engine is off, or possibly when I turn on the ignition and the electric pump starts. Seems crazy to think that a piece of dirt that large could make it through the pump, pre-filter, and post filter all the way to the carb. Any ideas of what else I might be facing??

Just set to 15 btdc right now.

Well, it was a junkyard head. Took a lot of cleaning up to run on the L24, seemed to be leaking at every valve. We (I say we, but it's actually a buddy of mine) have storage units full of oddball stuff, including an original '64 fairlady roadster, short window, etc etc. The head just happened to be sitting my the 240z, and we decided the E31 was probably a bad idea to put back on. HMM.. I'll see what I can do with the timing tomorrow. I'm starting to get backfiring out of the carbs upon cold starts. Gotta see what's up with that. The triples and big cam are waiting on some bills to be paid, and my L28 to be built first. No sense wasting all that money on a bone stock worn out motor. I changed the oil in the carbs out for some Marvel Mystery Oil (suggested by a local) and it's a LOT peppier. Revs a lot quicker to 6000. Still not very quick though. I've been playing with my fuel adjustments over the last few days and can't get the damn thing to stop running so rich. Even at 2 1/4 turns down, it's still obviously rich when cruising. Double checked needle height, and float levels, don't understand why she's running so rich. I need to invest money in a new innovate LC-1 and replace the clock. i had one in my truck, and it kicked arse. Also noticed that when in second under about half throttle to 5000rpm, it starts to surge a little. Not sure if that has to do with it running rich or not. That was with the mN47 head, I've since then rebuilt a spare L28 N47 and slapped it on to straighten that out. Stock N47 cam. Is there a difference between different L-6 cams other then internal/external oiling?

Thanks Carl! I think I'll buy some time while I work towards a new daily driver. I was able to do some WONDERS with the right products. Fine grit Meguiers compound, and Ultimate Polish. No wax 'yet.' I have a lot more work to do, but here she is! After C&O last month, you guys really kicked my arse into high gear. My car was the nastiest of the group. HUGE difference over stock. (This was after getting it home. Look how nasty the hood is.) And because I'm feeling nostalgic, my old '75 620. Had a built long rod stroker, .475 Racer brown cam, etc etc. Man I miss that truck.

Sorry let me clarify. The car had a blown head gasket and fatally wounded E31 on it We swapped it for a Maxima N47 junkyard head for the time being to get it running. Compression tested 90psi across the board, 110 wet. Rebuilt a spare N47 on the side and swapped it in a few weeks ago. It was running awesome at one point with the shot mN47. It has a ZX matchbox at the moment, fresh cap/rotor/wires/BPR5EY NGK plugs, etc etc. Literally everything 'tune up' related is new. Electric fuel pump with regulator @3.5psi, insulated fuel rail and fuel lines. Tonight a buddy of mine stopped by with my E31 head from his shop, got to talking about it, and didn't even occur the oil I'm running in the dashpots may be WAY too thick. It's either 10-30 or 10-40, the pistons are TIGHT. I'm going to pull the pistons tomorrow, drain and clean all the oil out, and fill it with ATF. I've been meaning to do that but forgot. That's a huge performance killer, and would explain my crappy gas mileage too. Steve, I'm lazy and keep forgetting to do that. I'm on it some day this week. I have a lot of learning to do! I need to sit down and pick Tims mind.

Hey guys, just want to clarify my intentions: My 70 240 is seemingly on the low side of the power spectrum, and I KNOW I have a lot to be found. It's not my first L motor, but it is my first L-6 and my first set of side drafts. I feel like at one point it made a scary amount of power, but now I'm starting to feel like I'm lacking. My L24 has a stock bottom end with flat-tops, and an N47 head to replace to shot E31 that's undergoing a rebuild for my L28 build. For the time being I'm making do with what I have but I feel like I'm not getting enough power. It's got stock manifolds, bone stock exhaust with the original glasspack, etc etc. I JUST rebuild my N47 from the ground up to restore some lost compression, lapped valves, fresh seals, etc etc... The L24 service manual on Xenons30.com shows the timing table on the crank pulley is in 5 degree increments... I'm assuming the table starts at 0 degrees, correct? If that is so, I'm running about 13 degrees static timing. I believe I may also be loosing something in the carbs somewhere. Despite my attempts to dial in my SU's with my Uni-syn and lots of reading some walk through's, I can't help but feel like I'm doing something wrong. When I start my car, I notice that it distinctly sounds as if one carb is dead until a few quick revs, and all is well. I've followed all the guides on here, and don't seem to get any difference out of it. I'm 2.5 turns down on the nozzles, disassembled the carbs down to every piece when i rebuilt them, carefully reset the needles, blah blah, etc etc. Is there any common mistake made by SU newbies that I might be overlooking? I'm sure there's something obvious only an SU noob would overlook...

Thank for the responses guys, I've not had much time to look at it. I'm not entirely sure how much play is 'normal' in these linkages, as I'm not very familiar with this type of assembly, and I've never owned a set of side drafts until about 5 months ago. Also, Bruce I spoke to you on the phone the other day about some needles and nozzles. Thanks for the prompt answer! Can't say I've ever dealt with any other company out there (let alone in the Datsun community) that has been able to answer a question so quickly without hesitation. I'll give ya a shout back once I know I need them. Just wanted to put that out in the open. You guys rock.

Hey guys, just curious, is there any kind of bushing that goes between throttle rod, and where it attaches to the U shaped piece at the balance tube? (Pic for reference) I've got quite a bit of play and I'm loosing probably 15-20% throttle with the pedal nailed down. I'm pretty sure the PO's 'mechanic' messed something up in there.

GOT IT. Turns out, the damn master cylinder push rod was too short. Swung by the parts store to swap it for another (assuming it was possibly leaking) and realized the new one had about 1 1/2'' longer pushrod. Autoparts store FAIL.

Also, does the piston in the slave have to be bottomed in the bore to adjust? I can spin my adjustment nut ALL day and not get anywhere...

No return spring on mine. Strange issue I'm having with the adjustment is that I can turn the slave cylinder adjustment rod and have literally NO movement of the clutch arm. It's like it's pushing the piston back, instead of the arm forwards. Sounds like air in the clutch correct? The air would be compressed before the fluid would create enough pressure to push the clutch arm, resulting in loss of movement and possibly, the ability to adjust? I actually was able to adjust the OLD clutch before the trans was out... now with the new trans in, I can't get the damn thing to adjust... EDIT: To be honest, now that I think about it I've had the master adjustments literally about maxed out since I put it on. Is there any possibility that I still have air trapped in the master, and the new clutch disk (being thicker) would require more motion from the clutch?

Just FYI, you guys should be using a Napa Gold (wix) 1515. Not sure if Wix and Napa PN's are the same (even though they're the same manufacturer) it's a larger capacity filter like pictured on the left. EDIT WIX #51515 Napa Gold #1515

Hey guys, just swapped the clutch on my '70 240 and I'm having issues getting into gear. Let me start by telling you what I've done: Master Cylinder and Slave Cylinder are both literally brand new. Less then 4000 miles on both, and no leakage. I swapped the blown out clutch disk with a spare 225mm clutch disk from my Datto truck. Bother were identical. The PP was quite different so I opted not to change that since I'll be pulling the L24 for an L28 in the future and I'll be using a different clutch. I've got my master cylinder and slave cylinder adjustments maxed out. I 'appear' to have full clutch arm movement, but it seems I may have a dead spot in the pedal. I've bled a large amount of fluid through the slave and gotten NO air out of it. Where do I start????

Yessir! Unless something at work comes up I'll be there! Actually, I've used the Meguires Ultimate Compound and Polish, then Waxed with the same stuff. Turned out great! Only issue is that It tends to fade quickly and water-spot easily. I don't know if it's Georgia's acidic rain, or an issue with the pain but unless you polish often it tends to look like crap after a wash.

Just wanted to share some pictures of my recent progress Hope you guys enjoy! _DSC0521 by metalmonkey47, on Flickr Lucy by metalmonkey47, on Flickr Lucy by metalmonkey47, on Flickr Lucy by metalmonkey47, on Flickr

Thanks guys! I feel absolutely stupid for not noticing that, I popped them all out and couldn't manage to recover any of the pins, so I'm just going to order a big mess of them. Also didn't have as much speaker wire as I though, so I used some of my large gauge primary wire. Fail on my part, I need to stock up on audio wire.

Is there any 'easy' way to do this? I'm trying to remove all of my interior trim to run new speaker wires, but the damn panel retainers are so small and tight I can't get any to pop out. My interior is perfect and crack free and I want it to remain that way. I also have no broken or missing panel retainers. I also like that.

Sorry about the delay guys, I figured it out last week. The needle in the rear carb was bent so slightly, the piston wasn't dropping all the way. It sat about 1/4'' above the venturi. Now it runs a lot better after straightening the needle. i'm going to order new needles and nozzles from Z therapy soon.

I'm hoping on being there myself.

You know it's kind of funny, I had a similar concern driving my 620 with a built LZ all the way through Atlanta to the airport at 6 AM to go get a friend, and never really trusted my car to make the trip, but it did it wonderfully! Cruising sucked since it had a 4.375 rear gear, but otherwise I actually had a great time with no issues! It gave me a chance to learn a lot about my car, and asses quite a few issues that I was able to fix, since I had a lot of seat time with them.

I literally had NO idea what either one of the knobs did under the dash until Ir read that, WOW! Alas, it didn't fix the issue, but damn did it make me feel a little less stupid. I will surely take you up on that offer once I get this thing running better. I thought i'd share a little update. I'll be back with many more pictures, but man I love cheap radiators. $131 on Egay, not the best quality but by far better then the busted one I had.

Well they aren't even, I had to drop the needle on the rear carb about 1mm further to help lessen the rich running issues... didn't do much, so I have a feeling it's getting fuel another way. They're about 2 turns down, give or take about 1 turn. Timing is dead on, about 30 degrees @3000 rpm and 10 degrees at idle. I'm going to replace the plugs today. They are pretty shot.