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-   -   Car only starts with starting fluid. (https://www.rx7club.com/1st-generation-specific-1979-1985-18/car-only-starts-starting-fluid-786075/)

NCross 09-10-08 09:31 PM

Car only starts with starting fluid.
 
So I put a new pressure regulator on it. It runs fantastic now except... it will not start under its own power. You have to spray a couple spritzes of starter fluid in the carb. If it's been running for a few minutes and you cut it off it will restart. You can't let it sit for more than 5 minutes or so though or the gas left in the carb will evaporate and you have to spray starter fluid.

What do I need to adjust to hopefully get this thing to start off gasoline every start up?

I need to fine tune it to get the idle down under 1000RPM. Right now it idles pretty steady between 1000-1200RPM depending on temperature and how warm the engine is. Mixture screws are open maybe 3-4 turns (set at where the idle sits happily). Fuel PSI is set at 4.5.

currently no filter element (I know I need one, just haven't yet)
Weber 45 dcoe
MR Gasket 0.5-5.5 PSI fuel regulator
RB intake
header, 2.5" exhaust with one replacement cat

The car holds idle pretty well right now and drives pretty smooth and pulls hard.

Also... should there be a spot to connect the tank return line? I see a couple spots where I could tap into I guess, but I'm not sure if it will rob pressure from the carb.

darkfrost 09-10-08 09:36 PM

I doubt its the FPR causing your current problem, but the Mr.Gasket FPRs suck for rotaries. They choke under high rpm and will lean out your engine.

I used one for the longest time on a dual Weber setup and the dyno revealed it wasn't flowing enough fuel past about 6000rpm. After replacing it with a Holley, the car pulled a lot better.

NCross 09-10-08 09:41 PM

The Holley I had on it got stuck open to full pressure so I swapped it out. The FPR I'm currently running seems to pull quite hard up to 6700RPM where I've been shifting on my test runs. I have noticed when I pull to 6700RPM and shift to 2nd gear and gas it it will sputter a bit sometimes. I blame that on my spark plugs. NGK 9 heat range. I need to buy some 7 range plugs.

BTW I am also using a Holley electric fuel pump. It used to be that you could turn the key to ACC and see a little fuel dribbling out of the jets into the carb (when I had the dying Holley FPR installed). When you turn the key to ACC with the MR.Gasket FPR it does not dribble at all.

NCross 09-10-08 09:46 PM

Do you think I need to put a filter on it to "choke" it a little bit so the gas will not evaporate as much? I'm in between jobs right now (fancy term for I quit!) so I don't need to spend money until I get a paycheck.

brandon davis 09-10-08 10:03 PM

are you sure the fuel is evaporating? If its dripping out and down the carb/ intake manny then this too could cause your problem?

NCross 09-10-08 10:12 PM

Well my theory... is that it's evaporating whatever little bit still remains in the carb after shutting the car off.

I'm saying this because when you go to start it up cold it will sputter to 1000RPM or so for a fraction of a millisecond and die, then when you re-engage the starter it will just crank and crank with no sputters as if the fuel pump is unplugged, which I can hear it running. You know the sound the rotaries make when they are about to start, but don't. Kind of a rapid E E E E E E then usually it starts, but the fuel just isn't there. If it were flooded the starter fluid would just add to the problem and not start. Starter fluid gets it started every time no problem.

I just would hate to look like a tard and have my car die in traffic and have to get out, open the hood, spray starter fluid, close hood, then get back in and start it. Same goes for if I go into the grocery store for 25 minutes and come out and have to do the same.

Is there maybe a screw to adjust the float levels? Or maybe an air bleed or something that may help?

kalvinr083 07-15-20 11:51 PM

Hi I know I'm a good 11 years and some late, but I was wondering if you ever solved the issue my 83 GSL is doing the exact same thing as your Rx7 its only starts with starter fluid but idles and runs around 1,000 Rpms


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