New Z Owner trying to get things going

[bringingbacka78]

i recently bought a '78 280z for 500 bucks it wasn't running when i got it the guy i bought it from told me it had been sitting for about 4 years and the motor was rebuilt about a year before that. anyways it wasn't getting any fuel to the motor. i found the fuel line was rusted solid and the lines going in and out the tank were clogged i ran a new line replaced the fuel filter and pump and dropped the tank, blew the tank lines out with air and she runs.... i drove it around the block a couple of times the last few weeks but the first time i drove it for more than about 10 minutes it was running fine and then it suddenly died, i tried to restart it and it ran for about 10 seconds at about 450 rpms and blew a cloud of dark smoke before dying. i figured i'd blown the motor or something but the next day it started up fine and idled good i am confused. i read about the gas tank demon and i'm leaning toward that because of the other fuel issues:stupid: just wanted some input from someone who knows more about Z's than i do

[sblake01]

Sounds familiar. When I bought my 78 about ten years ago it had the same symptoms. I did basically the same things you did. Ultimately it did end up being the tank. You can continue to clean the fuel lines and it will run for a while but to cure the problem you'll have to clean or replace the tank. I thought I had it solved a couple of times before I dropped the tank but as soon as the stuff got stirred around enough it would clog up and stall.

[bringingbacka78]

thanks i checked into having the tank cleaned and coated they want $127 so it's not too bad if it's gonna fix the problem. i'm gonna install an in-line filter before the pump too because it's new hopefully i'll get to move on to the next headache none of the gauges are working except for the speedo and tach..

[sblake01]

none of the gauges are working except for the speedo and tach..

That would depend on which ones don't work. A bad ignition relay can cause the temp/oil and the fuel part of the volt/fuel not to work. I've had that happen. The clock is seperate and has it's own symptoms. Fuses can cause them all not to work as well as dirty connections. There is not just one thing that will cause them all to fail at the same time. Do you have a FSM? There's a guage section somewhere in the Body Electrical section.

[bringingbacka78]

well when i first got the car only the volts and clock worked now just the clock so maybe the ignition relay is the culprit would the car still operate normal if the ignition relay was bad?

[bringingbacka78]

also if the voltmeter is not affected by the relay what might have caused that one to stop working all of a sudden? thanks this is the kind of stuff i need to learn

[sblake01]

The voltmeter should register voltage even when the ignition is off so it doesn't go through the ignition relay. I would check and clean all of the electrical connections at the guages and the relays. Sometimes that ends up being the only problem.

[Rockr69]

Stephen, Dan here, any ideas on why my oil press. gauge goes to maximum when I start my car then slowly dies off to zero? Thanks

[sblake01]

That can only be the sending unit or the guage itself. I would lean toward the guage since a bad sender usually won't cause that surge to maximum before it dies off.