1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

It starts but...... (help please)

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Old 08-09-09, 11:37 AM
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It starts but...... (help please)

So I bought this 100 dollar 85 FB with the 1.1L carbed 12A. It has been sitting for 2 years. I got it started but it bogs down if I press the throttle down. I can accelerate if I touch the throttle just right. If I let it run it will just die after 5 to 10 minutes. All in all I have replace the Battery, Starter and the Ignition Switch. If I let it sit for a few days it takes forever to start again. After I started it and moved it I disconnected the fuel lines. No fuel came out. Is that normal for a carbed motor? I am guessing I should replace the Fuel pump (the kid had a new one put in RIGHT BEFORE he let it sit) and the fuel filter. I think this should make it run right. It has a new Nikki Carb on it as well. I just want some more input before I put more money into it. Given All I have spent on this car (including the cost of buying it) is just over $450. I am just saving up for a new motor in my FC with a tranny rebuild. What do you guys think?
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Old 08-09-09, 03:26 PM
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Fuel filter is probably a safe bet. if the cars been sitting with gas in the tank for 2 years its probably got all kinds of sediment that got sucked up when you started it again. Either way its a cheap fix and something that you should do anyways. Do a full filter/fluid swap
Old 08-09-09, 07:00 PM
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Good chance the clog is in the fuel tank and pickup, since everything else has been dealt with. Time to drain, drop and clean the fuel tank and rod out the pickup tube. Wouldn't hurt to blow out the fuel lines either with carb/brake cleaner and compressed air.

Freshly rebuilt Nikkis have a habit of the new needles sticking and flooding the engine. A light tap on the banjo bolt above them is often all that's needed to loosen them.
Old 09-04-09, 05:47 PM
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wow. Thanks. Good info trochoid
Old 09-04-09, 06:35 PM
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84-85 have a fuel pump relay, it doesnt pump fuel unless the engine is turning.
Old 09-06-09, 01:55 AM
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My problem is that it shuts down after the cars warms up
Old 09-06-09, 12:46 PM
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Originally Posted by NCGNETO90
My problem is that it shuts down after the cars warms up
i had one kinda like that, pump would work with the key on, but it would turn off when the engine started. mine turned out to be the ecu/control unit/emissions box thing. i ended up bypassing the relay so it just turned on with the key like an 83 and earlier rx.

although if your tach shuts off when the fuel pump shuts off, its the trailing ignitor
Old 09-06-09, 03:45 PM
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Originally Posted by NCGNETO90
My problem is that it shuts down after the cars warms up
Sounds fuel related, but this hose is easy to check.
https://www.rx7club.com/1st-generation-specific-1979-1985-18/hose-question-750125/
Old 09-07-09, 05:07 PM
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I'd replace your spark plugs also. I bought my car after it sitting for a few years with a fresh rebuild Original motor overheated and died at about 230000 miles. all that was wrong with it when they parked it was it needed a new radiator and a new drive line. shook alot past 25 MPH. Well first thing I did was a full tune up cap, rotor, plugs, wires, fuel filter, oil change, air filter, ect. But the spark plugs were falling apart after 2 years. also the cap got chewed up by the rotor, so it really didn't want to start. since they've been replaced my car starts right up every time.
Old 09-07-09, 05:42 PM
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agreed
Old 09-07-09, 11:34 PM
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I put new factory spark plugs in there. I am also getting an upgraded fuel pump tomorrow. Lets see how that works out.
Old 09-08-09, 11:32 AM
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What kind of fuel pump? You have to keep in mind, the Nikki carb doesn't require much pressure to run (about 2psi), so if your new pump runs a higher pressure than that, you will need a fuel pressure regulator to keep you from overpowering the carb...


.
Old 09-08-09, 06:10 PM
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I just got it today. It is from RB.
Old 09-08-09, 07:09 PM
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Originally Posted by Kentetsu
What kind of fuel pump? You have to keep in mind, the Nikki carb doesn't require much pressure to run (about 2psi), so if your new pump runs a higher pressure than that, you will need a fuel pressure regulator to keep you from overpowering the carb...


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im running a universal fuel pump at 35 gph at 5-7 psi and my 7 runs great got it at shucks for 30 bucks
Old 09-09-09, 04:41 AM
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Originally Posted by theFBthatcould
im running a universal fuel pump at 35 gph at 5-7 psi and my 7 runs great got it at shucks for 30 bucks
Stock fuel pressure should be 2.83-3.55. If you are running 5-7 psi into a stock Nikki carb, your car could be running better.
Old 09-09-09, 01:41 PM
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Originally Posted by 74RX4
Stock fuel pressure should be 2.83-3.55. If you are running 5-7 psi into a stock Nikki carb, your car could be running better.
sry for the jack but wats the max gph and psi that a stock nikki can handle?
Old 09-09-09, 05:18 PM
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Can't say what is maximum, but FSM lists specs for different years. Not much difference. 84 FSM says 2.84-3.54 psi at 1400 cc per minute or more.
Old 09-24-09, 12:00 AM
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Stock should be 3.2ish.
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