1978 fuel pump issue

[THorsma]

I'm working on a 1978 280Z that sat for a few years with out running and am hoping for a little advise. I changed the fuel pump and then realized I may have an electrical issue (fuel pump is not pumping). Possible a fuel pump realy. Any thoughts would be appreciated.

Thank you.

[FastWoman]

It COULD be the relay. You'll find it inside that black box attached to the passenger-side inner fender. It could also be a bad contact in one of the big wiring harness connectors just inside the passenger-side firewall. As I recall, it's a blue/green wire in the corner of one of them. Mine had become hopelessly crusty and melted, so I broke it out of the connector and connected it with a bullet connector.

Note that your fuel pump won't run any longer than 5 sec when you turn the key to START. Beyond that, it won't run again until the engine is actually running and has either oil pressure or voltage. In the '78, there's no longer any fuel pump shutoff switch in the airflow meter. Failure for the pump to operate could be attributable to the oil pressure switch AND alternator output. (Both would have to fail.)

I see you're new. You can download your own FREE copy of the Nissan Factory Service Manual here:

http://www.xenons30.com/reference.html

It's a very good manual and will be invaluable for tracing stuff like this. A paper copy is even better. You can pick those up used on Ebay or Amazon from time to time.

Edited June 27, 2011 by FastWoman

[THorsma]

Thank you for the information. I'm hoping my z looks as good as yours some day.

[FastWoman]

Thanks! And you're welcome!

[sam74260]

mines doing the same thing, i ran a ground from the battery just to check it, sure enough it kicked in. mine too sat for 7-8 years so we got alot of cleaning to do on the connectors, hope this helps

[THorsma]

Thanks for the info. My Z sat in my brother's back yard under a tree for 12 years. After she's running, I have a little rust work to do.

Thanks again.

[argniest]

That is awesome! Glad you are working on it! You wont regret it! They are so much fun! I cannot believe how many people wave at me, honk their horns, kids yelling COOL CAR MAN! Adults doing the same, perfect strangers coming up and talking to me about it, people telling me stories about their Z car in the 70's or 80's, lots of people want to race me, it just goes on and on. Talk about a head turner!!! Living in the midwest also, there were not as many Z's here I figure. And I have only seen 1 other 280 Z in 3 years now.

I never expected this much attention....but it is fun!

I had an aftermarket fuel pump, and my gas tank as I found out (after opening the inspection plate in the back of my 1978), I saw an inch or two deep of rust INSIDE THE GAS TANK!!!!!

You might be dealing with that problem too.

But my first step, I decided to remove the fuel filter, and cut it open, and omg! it was filled with rust. Thats when I figured i better just look inside the tank with flashlight. Once I saw that, I knew I needed to remove the gas tank and have it professionally cleaned and sealed up. Now it will probably be rust free inside for a few hundred years

Be careful messing with gasoline! I was scared to death messing with the gas tank, was very careful. And it led to many other things being replaced, that are well documented on this forum.

Edited July 18, 2011 by argniest