ArneA

I recently got my Rx7 running, was sold to me as non running. I had trouble starting it first until I discovered pulling and pushing the choke in a few times before starting it works perfectly, if I just pull on it it won't start and will just spin. I changed the spark plugs to brand new ones, I have a new fuel pump I haven't installed yet and a fuel filter.
When the engine starts cold the choke stays in its outward place and it climbs up to 3000 RPM so I have to push it back in and I leave it at 2000 RPM, I can leave it at 1800 but any lower and the engine slowly bogs down and shuts off. I let the engine warm up for 12 minutes at 2000 RPM, I tried pushing it in a bit then, got it to around 1400 RPM +/- , the choke tries to retract so I have to keep it in place, any lower than that RPM and it shuts off too, so It doesn't idle.

Do I need to rebuild my carbureter for this? Or just adjust it? I haven't touched the carb yet

GSLSEforme

Check for vacuum leaks,try adjusting mixture and idle screws and see if it helps or changes symptoms. If car has been sitting long enough,carburetor,fuel system in general will need some attention. Have you inspected,changed fuel filter? Its condition will be an indicator of which direction to proceed with repairs.
Some have had success with spraying down carbs with carb cleaner to clean them up. Seafoam run through fuel system has had good effects on no/poor idle complaints

ArneA

Thanks for the reply, I will check all of that tomorrow and replace the fuel filter for sure.
I'll start by looking for vacuum leaks!

ArneA

Today I removed the fuel filter, it was really really dirty filled with rust that has been sitting in the fuel tank for a while, I did pump out the fuel before and put new in and then re drained it again.
Here's a picture of the filter
What does this tell me? Could this be one of the causes? (There was at least 4x more of this goo inside of it)

GSLSEforme

Some of what you see there will have made its way to the carburetor and most likely responsible for car not running(idling) correctly. The rust seen there will have come from the fuel tank . You will need to address the complete fuel system starting with the tank and ending with a thorough cleaning/rebuilding of the carburetor.
Logical steps to take:
-Drain,remove,inspect fuel tank. Worst case scenario,the tank is rusted beyond repair and another non rusted used one will need to be sourced. It may be possible to have the tank cleaned,in this country radiator repair shops can clean tank chemically and afterwards a coating can be put on/in tank to keep from further rusting.
The fuel sender unit and fuel pickup and sock will need attention or replacement also. Does the gas gauge work?

-Fuel filter replaced,replace fuel pump for two reasons,it will have rust and contaminants in it and it's 30+ years old.

-Metal fuel and return lines from front to back of car will need to be thoroughly flushed,possibly replaced if rusty or rust cannot be cleaned out. All rubber fuel line should be replaced due to contaminants and age.

-Carburetor must be removed,completely disassembled and cleaned/dipped in a carburetor cleaning solution maybe more than once,same for all jets,air bleeds,etc. There are some dos and don'ts concerning gaskets and needles and seats,and floats. Lot of info on this website pertaining to the Nikki carb on your car. A couple are,,,do not attempt to adjust the floats,majority of time are correctly adjusted from factory and attempts at doing so are problematic. The rebuild kits available(worldwide to my knowledge) have poor quality replacement needles and seats which when used cause repeated flooding. The needles can be used(after burnishing to remove sharp edges) if the originals are trashed but the replacement seats are machined poorly and should not be. The airhorn gasket is also very thin and should only be used as a template to cut a better one out of thicker gasket material. The gasket beneath the carb is part of phenolic block to which it's attached and should be able to be reused.

Recommend replacing all vacuum hose underhood and on rats nest to prevent inevitable leaks from splitting and cracking from age

Once fuel system is overhauled car should start,run,drive reliably. Correct spark plugs,cap,rotor and plug wires should be replaced as necessary.

KYPREO

Probably should have changed the fuel filter and drained the fuel tank before starting, as KansusCityREPU recommended and I seconded in your other thread! New coolant, new oil, new spark plugs, new fuel filter, fresh fuel. All of this is a must. Now you've got to clean out the crud from the rest of the fuel system.

spokanerxdude

iTrader: (4)

Just for information purposes, 79 and 80 are SA's and, 81 to 85 are FB's

KansasCityREPU

iTrader: (9)

He's in Belgium. The foreign markets for the way first gen rx-7's where optioned where completely different then the U.S.

t_g_farrell

iTrader: (1)

That has to be the nastiest filter I have ever seen.

KansasCityREPU

iTrader: (9)

For added protection, I'd be inclined to add another filter by the carb after everything is clean. It makes it easier to monitor the condition of the fuel system.

t_g_farrell

iTrader: (1)

Yeah, good idea. Use a glass one that you can see thru if you can get one.

ArneA

I did drain the fuel tank and poured new fuel in, and then pumped that fuel out and replaced it again before starting it the first time, I didnt change the filter though. The car has a new fuel filter now and I will buy a second filter now to place near the carburetor. The car has a stock exhaust

I think I found out why my car doesn't IDLE, according to some people the previous owner started to remove the emissions stuff on the car, removing the ratsnest and so on but didn't finish it, I have a few pictures of it: I'll try to fix this and see it it changes how my car idles, else I will rebuild the carb, I will also get my fuel tank restored sometime soon and as much of the fuel line as possible,







I'm not exactly sure what to do at this point, either put it back the way it was and purchase the parts again or finish what the PO started, I don't want to fail the SMOG test when I go to register my car, I'm not even sure if they test "oldtimers" for SMOG here or how strict they are about it.

GSLSEforme

1st thing you should do is inquire what is involved in passing smog test. Most places(states) in this country that have emissions testing programs have a visual aspect to the test where the vehicle is inspected to verify all original emissions equipment is in place on the vehicle.
In the state i'm certified to do safety and emissions inspections,if the vehicle does not have all oe emission components in place,it's an automatic fail and test goes no further.

Regarding your plans for the fuel system,recommend you start at source of fuel contamination. No point in cleaning carburetor,lines replacing filters until tank situation is addressed. This may not be popular advice to hear but in the long run it will be the most cost effective partly due to the fact you'll only have to do all this once whereas not handling the tank situation 1st will have you doing everything else fuel related several times with temporary success at best.