Porsche Husky Posted October 29, 2010 Share Posted October 29, 2010 Hiya! I thought I'd finally join the forums after a year of simply watching what goes on Anyway, I've gotten my first S30, a 260 to be precise. I've gotten the engine rebuilt already (that was a rollercoaster ride... more will be explained later) and a mass of the body work done. However I seem to be having some problems with the fuel pump. A mass of people have told me the pump only kicks on when the car is idling, which... honestly doesn't add up to me. Is it possible that a relay has blown for it? and if so, where can I locate it? I'm such a n00b I'll have pictures of the project and a story on how I got Zeddy (yes I named him ) soon enough. Quote Link to comment Share on other sites More sharing options...
BluDestiny Posted October 31, 2010 Share Posted October 31, 2010 Mechanical fuel pump or electric? Quote Link to comment Share on other sites More sharing options...
Porsche Husky Posted November 7, 2010 Author Share Posted November 7, 2010 The electric one. However; if I remember correctly, don't these cars use alternator input and 400+ RPM input as reference to power on the pump? I guess what I mean is, my tach doesn't work so since it doesn't work, will it somehow not tell my pump that the engine is spinning? Which I guess has another question within itself, how is my tach controlled? What wires do I need to connect or cables to make it work? Quote Link to comment Share on other sites More sharing options...
cgsheen Posted November 7, 2010 Share Posted November 7, 2010 Hey fellow 260 owner! Better get the Factory Service Manual. The electric fuel pump has 2 cut-off relays (under the passenger side dash with all the other relays I think). One is controlled by the "N" signal from the voltage regulator (so when the engine spins over 400 RPM (and spins up the Alternator I imagine) it "knows" the engine is doing more than cranking...). The other one "senses" the starter engagement and holds the fuel pump off when the starter is engaged. They run in series so either one (or both) can keep the pump from working. Now I'm really glad mine is controlled by the ECU through one relay! Quote Link to comment Share on other sites More sharing options...
Porsche Husky Posted November 7, 2010 Author Share Posted November 7, 2010 Hey fellow 260 owner! Better get the Factory Service Manual. The electric fuel pump has 2 cut-off relays (under the passenger side dash with all the other relays I think). One is controlled by the "N" signal from the voltage regulator (so when the engine spins over 400 RPM (and spins up the Alternator I imagine) it "knows" the engine is doing more than cranking...). The other one "senses" the starter engagement and holds the fuel pump off when the starter is engaged. They run in series so either one (or both) can keep the pump from working. Now I'm really glad mine is controlled by the ECU through one relay! I got it working some stupid guy *coughmecough* crossed the wires so the pump naturally wouldn't energize lol I've got it fixed though and it purrs well... it did, till I found out the piping was so rusted away that it literally BLEW a hole in the piping just after the manifold lol Sounded like a gunshot at first, nearly made me jump. I guess now the only problems I'm faced with are; 1. Brake servo is causing a massive vac leak and the fact there is no feeling of pressure when I go for the brakes (me thinks it dead ) 2. My tach doesn't work and have no clue where or what it ties into, all my fuses are good so I'm assuming it has to be something in the engine bay. 3. My clutch doesn't disengage 100% I bought my slave cylinder from eBay parts wholesaler who has a mass of Datsun parts. I'm getting the feeling the rod may not be long enough to fully disengage the clutch. is this possible? I've bled the clutch several times just to confirm it wasn't trapped air and it doesn't appear to be any air in the system. Are there any stickies on this forum that have a good write-up on any of those problems? So far that's it for now. I'll be able to find out more once I get that stuff taken care of and have it on the road (which I'm sure tons other things will suddenly pop up lol) Quote Link to comment Share on other sites More sharing options...
cgsheen Posted November 8, 2010 Share Posted November 8, 2010 1. Mine too. I've thought about replacing the brake booster over the last year and a half (my kids think I'm crazy that I haven't...) but I just capped the Vac line to the servo... I'm an old guy and "power brakes" weren't all that common when I learned to drive (disc brakes came even later...). Personally I like the feel and I can still stop this thing on a dime so I don't really need the booster. 2. The Tach signal comes off the blue wire to the coil from the transistor Ign unit. Blue wire tees off to a big square resistor about the size of your fingertip, through the resistor to the Tach... (Pretty sure the resistor in mine was visable outside the Dash wiring harness under the glove box.) 3. Some adjustment on the rod that engages the clutch master cylinder - a PITA to get to under the dash - on the top of the clutch pedal. If there's not enough adjustment there, Main adjustment is inside the bell housing behind the throw-out bearing fork. There's an adjustable "pivot bolt" that needs to be set correctly before the tranny gets mounted... No adjustment at all on the 260Z slave cylinder. (although my manual says early 240's had an adjustable push-rod on the slave...) Quote Link to comment Share on other sites More sharing options...
Pharaohabq Posted November 8, 2010 Share Posted November 8, 2010 Welcome to Hybridz.org... Yeah that clutch can be a pain in the butt. If it was brakes I'd be thinking reaction disc. You might have to drop the tranny to adjust the main fork adjuster. it's got a nut that's supposed to hold it, but sometimes that works loose. Oh CGSheen, don't ride behind me, I guarantee my stock brakes with a booster will stop a heck of a lot faster than your "manual" brakes will. Quote Link to comment Share on other sites More sharing options...
cgsheen Posted November 10, 2010 Share Posted November 10, 2010 Oh CGSheen, don't ride behind me, I guarantee my stock brakes with a booster will stop a heck of a lot faster than your "manual" brakes will. I'll swerve to miss you! Quote Link to comment Share on other sites More sharing options...
Porsche Husky Posted November 15, 2010 Author Share Posted November 15, 2010 1. Mine too. I've thought about replacing the brake booster over the last year and a half (my kids think I'm crazy that I haven't...) but I just capped the Vac line to the servo... I'm an old guy and "power brakes" weren't all that common when I learned to drive (disc brakes came even later...). Personally I like the feel and I can still stop this thing on a dime so I don't really need the booster. 2. The Tach signal comes off the blue wire to the coil from the transistor Ign unit. Blue wire tees off to a big square resistor about the size of your fingertip, through the resistor to the Tach... (Pretty sure the resistor in mine was visable outside the Dash wiring harness under the glove box.) 3. Some adjustment on the rod that engages the clutch master cylinder - a PITA to get to under the dash - on the top of the clutch pedal. If there's not enough adjustment there, Main adjustment is inside the bell housing behind the throw-out bearing fork. There's an adjustable "pivot bolt" that needs to be set correctly before the tranny gets mounted... No adjustment at all on the 260Z slave cylinder. (although my manual says early 240's had an adjustable push-rod on the slave...) Yea I see what you mean about just going strictly manual with the brakes, Until I get the money for another one the feel of a manual system is much more firm anyway... plus I've had horrific experiences in my Porsche when the servo in it died, probably came close to having my first massive heart attack lol. And I've found the blue wire near my coil. Everyone I've told about this; the first thing out of their mouth is 'the tach is dead' when I personally can't see that, the car has been sitting in a garage since 1982 and never moved until July 2009 (day I bought it) so for the solders to be no good on a car that is practically 'new', does that make sense or do the S30s really have a bad habit of electrical problems? Oh and I got the clutch problem fixed! Found out (the hard way) that the rod that comes with the reman. unit from the local part stores isn't as long as the OEM rod, infact; it's literally just a hair shorter but that little difference makes all the big difference in being able to do clean shifts or chow down on the gears for breakfast! So glad that is out of the way! I think my fork is ok on the inside but now that you mention it, I'm going to check it anyway to be sure since I have to tend to the transmission soon anyway (and a new clutch since my new pressure plate and disc just came in the mail last week ) As for the tach stuff though, I'll have a few pictures up soon just to clarify (or be yelled at) that I have everything connected properly. A friend of mine was trying to help me with it and practically getting upset with me that I wasn't getting it right (I'm a suspension and braking technology geek, engine and electrical are second rate to me since I like for my cars to hug the road and safety)yet this is also the same guy who didn't even know what a wheel cylinder is, which concerned me and made me question anything that came from his mouth lol Welcome to Hybridz.org... Yeah that clutch can be a pain in the butt. If it was brakes I'd be thinking reaction disc. You might have to drop the tranny to adjust the main fork adjuster. it's got a nut that's supposed to hold it, but sometimes that works loose. Oh CGSheen, don't ride behind me, I guarantee my stock brakes with a booster will stop a heck of a lot faster than your "manual" brakes will. Yea! I read something about the reaction disc in the FSM! However, I haven't found any repair kits for it. I'm almost 100% sure that thing is long dead though, especially after trying to drive it. WAs working fine as I was at the end of my driveway then I hear a considerably loud 'pop', my brake pressure dies and pedal hits the floor, the engine dies, then I am left pumping the mess out of the brakes to get any pressure... Scary feeling when you live in the woods and have a twisting driveway and have to coast backward all the way to the house in the dark, with louvers blocking your sight! Ugh! lol And thanks for the welcome! Quote Link to comment Share on other sites More sharing options...
cgsheen Posted November 18, 2010 Share Posted November 18, 2010 or do the S30s really have a bad habit of electrical problems? OH Ya! You'll find many a problem you may think "mechanical" will turn out to be "electrical"... Quote Link to comment Share on other sites More sharing options...
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