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-   -   83 gsl dies shortly after starting (https://www.rx7club.com/new-member-rx-7-technical-256/83-gsl-dies-shortly-after-starting-1085616/)

rx7inoregon 06-24-15 11:23 PM

83 gsl dies shortly after starting
 
Hi all! At my brains end here. Ive rebuilt the carb, eliminated all emissions, replaced the fuel pump and installed a holley fpr, and the crazy thing dies seconds after starting if it starts at all. The previous owner replaced the fuel pump and claimed to have had the tank cleaned. The carbs front bowl runs low very quick and the car dies. The fuel filter hardly has any fuel in it, just enough to keep it running. Are there any specific places i can check for restrictions in the fuel line, besides the check valve near the carb? PO had check valve reversed for some reason, its pointing right way now.

lduley 06-25-15 08:50 AM

83 gsl dies shortly after starting
 
Whats your FPR set at?

diabolical1 06-25-15 08:51 AM

i am going on the assumption that we're talking about the Nikki here. correct?

since you rebuilt the carb, check the floats. if you look up Nikki threads and posts by Jeff20B, he has identified a consistent flaw in the needles and seats that come with the rebuild kits. did you use the ones that came with the kit? if so, i would start there from the problems you describe.

also, where and how are you trying to set the pressure?

rx7inoregon 06-26-15 11:15 AM

Fuel pressure is set at 3psi, and it is entirely possible my float is bent because the float caught on the air horn gasket when i took it apart. I used a hygrade kit, and the issue occurs even when using the old needle and seat. Yes sorry, nikki carb.

diabolical1 06-27-15 07:23 AM

well, recheck the floats first since you've previously identified a potential issue with them.

where in the line did you place the regulator? if it still does it after you've checked the floats, trying bumping the pressure a touch. the reason i asked how you set the pressure is to see if you merely set it with a gauge and trusted that it was what the gauge said. i prefer to set my pressure to where the engine runs right, regardless of what a gauge says.

rx7inoregon 06-27-15 05:37 PM

Regulator is under hood, just before my nikki. Anyone able to post a pic of a properly adjusted float? The curved center tab doesnt look like the rear float's tab, which has no problems.

diabolical1 06-27-15 07:27 PM

re-reading what i wrote in my last post, scratch what i said about the pressure. i had forgotten that the problem is isolated to one side of the carb.

rx7inoregon 06-29-15 01:36 AM

Ha haa i messed with the floats too much, now fuels pouring into the carb. Maybe next time ill get it just right :/

rx7inoregon 07-04-15 01:00 AM

Floats are dialed in, fuel pressure set to 2.5 psi, new fuel filter installed. Flooded the crap out of it the day before doing the floats, had a hard time starting, but finally got it to idle steady at 900. Now my neighbors think I have a motorcycle... It sounds amazing, thanks everyone!

rx7inoregon 07-21-15 08:38 PM

Update: car only ran well until I tried going around the block. It ran perfect in my driveway, idled and revved beautifully for a half hour without stumbling, overheating, leaking or smoking. It did not like either turning or coming to a stop, not sure. Float levels in carb looks much better than before I adjusted the floats. I'm working on resoldering ecu and instrument panel now. Will post result...

diabolical1 07-22-15 06:13 PM

what about the filter in the tank?

rx7inoregon 07-22-15 10:34 PM

*smack on forehead* there's a filter IN the tank?!

diabolical1 07-23-15 12:39 AM

some people call it a filter "sock", but yes. i was spit-balling though, so just stick a pin in that idea for now.

look like you might not be done with the floats yet. :(

https://www.rx7club.com/1st-generati...-hills-277417/

https://www.rx7club.com/1st-generati...n-hill-594107/

rx7inoregon 07-24-15 09:24 PM

What do I have to do to get to the in tank filter?

diabolical1 07-24-15 10:51 PM

well, you'd have to drop the tank. the access to it is at the top of the tank. however, again, i think you might be better served having a go at the floats again.

you had mentioned that the car improved a great deal after your last adjustment, but then when you drove it it started acting up in turns and under braking, so like i said i threw out another possibility (i figured the sloshing around in the tank may stir debris if these's some in there). however, i went ahead and did some research on my own and now i think you should give the floats another go.

the choice is yours though. i will try to help either way.

rx7inoregon 07-25-15 10:27 PM

Well shame on me, now the poor thing won't even idle. The fuel level in the carb windows took a minute to begin filling, but did reach halfway point and stay there. It cranks and cranks, but won't catch. I have spark at all four plugs. Drivin me nuts. I've tried adjusting the idle screw, but do not know where that screw should be to begin with, like how far open the throttle plate should be.

diabolical1 07-27-15 12:41 PM


Originally Posted by rx7inoregon (Post 11945767)
Well shame on me, now the poor thing won't even idle. The fuel level in the carb windows took a minute to begin filling, but did reach halfway point and stay there.

that sounds like the floats still need attention and/or there is some kind of obstruction to fuel flow.

the adjustment screws are not really relevant now. if you've been playing with them, then you should close them and then reset them to the spec in the manual. that should put them in the general area of where they need to be so when the car is able to idle again, you can set them to what your engine needs.

rx7inoregon 07-27-15 04:31 PM

The screws are not effective if the engine isn't running. Lightly in, then three turns out for the mixture screw, but how many millimeters open should the throttle plate be (using the idle speed screw). I backed that screw out til I felt no resistance, then I turned it back in til I saw the throttle shaft begin to rotate. Did not see in fsm where this screw should be to achieve idle.

diabolical1 07-28-15 10:56 AM

i was reading another thread a little while ago and thought of you, so i figured i would throw this out there, too. lately, i've been seeing some guys having trouble with charcoal canisters. have you checked yours? have you noticed any extra pressure in the gas tank lately?

rx7inoregon 07-29-15 11:58 AM

I have never heard pressure or vacuum when I open my gas cap. Possible I have a leak somewhere, but even in 110 degree weather, I never smell gas odor. Not sure how to determine if charcoal canister is doing its job.

diabolical1 07-29-15 09:06 PM

well, it's probably fine then.

Jeroham Nieves Rivera 07-31-15 10:48 PM

I have a very similar issue and I don't know what else to do. I have done everything I could possibly think off and still won't run unless you pump the gas plenty of time or put gas directly to the barrels of the carb and even then it only runs at idle for a few seconds so if you find the issue I will appreciate the tips

diabolical1 07-31-15 11:12 PM


Originally Posted by Jeroham Nieves Rivera (Post 11948691)
I have a very similar issue and I don't know what else to do. I have done everything I could possibly think off and still won't run unless you pump the gas plenty of time or put gas directly to the barrels of the carb and even then it only runs at idle for a few seconds so if you find the issue I will appreciate the tips

welcome to the board. :)

have you checked for vacuum leaks?

Jeroham Nieves Rivera 07-31-15 11:19 PM

I haven't been able to. It won't give me enough time to get out and listen for any vacuum leak.

diabolical1 08-01-15 12:07 AM

well, you can try to turn up the idle until it does, or have someone hold the throttle just enough for it to idle, then check it with carb cleaner.

also, let's try not to clutter the OP's thread. search for one that fits a bit closer or start your own. :)


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