the never ending project. 71 super build

Yak about stuff. Just stuff.
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Super_Randy
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Re: the never ending project. 71 super build

im thinking the fuel filter is empty cause it's sucking back to the tank. there's no way the tank could suck the carb dry. that ether leaked or evaporated. don't know how, it's never happened before. the other option is that somehow the carb syphoned into the engine. don't know how that would be possible. but i have heard a glugging sound back there when i shut the car off. which would leave me to believe there's to much pressure and the needle is sticking open. but idk how it would drain the bowl down the carb throat if that were the case.

like i said im throwing shit at the wall at this point. im even considering getting out my old fuel pump (the one i couldn't find a while back) and putting it on there just to test. also considering changing the intake manifold gaskets. i used the original style metal ones. the heads are new and in theory are straight, the manifolds are over 50 years old with god knows how many heat cycles so... maybe paper gaskets?
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Super_Randy
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Re: the never ending project. 71 super build

well, i just tried it. still won't idle :evil: got it on the charger again cause why not. works great everywhere from 900rpm up to about 5000rpm. just won't f'ing idle :evil:
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Super_Randy
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Re: the never ending project. 71 super build

ok, had the battery on the charger all day. volt gauge in the car is now showing 12 volts again. fluke meter still shows the battery at 12.6. it cranks like crazy now, and i can read the time on the head unit again! haven't seen that sense i put the battery in. still won't idle. tomorrow (weather pending) im going to try my old fuel pump. if anything just for S&G.
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Super_Randy
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Re: the never ending project. 71 super build

ok, im not sick (had the flu back in Feb) and it's not raining, time to get back on it.
swapped out the fuel pump and lines, i know it has flow. i marked the level on the fuel filter to see if it's still draining.
when you crank it, it's back to backfiring out the carb :?
and i changed the connectors on the license plate light cause well just look at the pic. only now the light doesn't work. not sure if it worked before... probably should have checked it... i check the bulb and its fine, also check the fuses, so maybe corrosion?
so anyway, i did some stuff, but im not sure if it made any steps forward. productivity is overrated.
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Maddel
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Re: the never ending project. 71 super build

Super_Randy wrote: April 20th, 2024, 6:33 pm ... when you crank it, it's back to backfiring out the carb :?
Man... These carb & ignition issues are a PITA. :evil:
May be tackle the dual carb conversion right away?
Super_Randy wrote: April 20th, 2024, 6:33 pm... changed the connectors on the license plate light ... only now the light doesn't work. not sure if it worked before... probably should have checked it... i check the bulb and its fine, also check the fuses, so maybe corrosion?
Hmm... Corrosion may be.
There's a "Y-connector" as well as two ground spade-connectors worth checking behind the tar board at the passenger side wheel well.

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Also the wire from the engine compartment to the deck lid is sort of labyrinthine and well flexed.
May be a (hidden) cable break somewhere?
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Super_Randy
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Re: the never ending project. 71 super build

the light pigtail connectors are brown so they're pretty corroded. the other connectors should be ok. past experience tells me that if those have issues so do other lights and everything else is in working order. there is also a possibility the pigtail itself is bad, i got it out of a 77 parts car almost 20 years ago. i might just go ahead and replace it, i think they're pretty cheap and the rest of the car is fully rewired so why not do this to?

as for my backfiring and not idling issue. i have all new intake gaskets and copper gasket spray shit that is supposed to help with sealing and heat transfer. i also need to swap over to an alternator, pretty sure i have all the parts for that. ...minus maybe a fuel pump...
im also seriously starting to wonder if my firing order is off. im wondering what would happen if it was say 90 degrees off...

edit:
after doing some more research im wondering if its the spark plugs. i have NGK D7EA plugs and they're non resisted. i wonder if that's feeding "noise" into the ignition system :? the plugs i ran on my old engine are NGK BR6HS and they are resisted. i think im going to try replacing spark plugs.
Last edited by Super_Randy on April 21st, 2024, 3:29 pm, edited 1 time in total.
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Maddel
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Re: the never ending project. 71 super build

That sounds like a plan.

I also wondered if a wrong firing order can cause the erratic idle.
Back in the day I had a 094 distributor that was 90° off.
It blew the air filter off... :D
But the engine refused to fire up.
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Super_Randy
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Re: the never ending project. 71 super build

i actually did blow the air filter off back before i replaced the carb :lol: i think that's what damaged the throttle linkage bushings causing them to seep fuel and cause a vacuum leak.
the only thing, it wont idle for shit. but above 1000rpm its fine. runs just like its supposed to.

as of right now my plan is to pick up new DR7EA plugs sometime this next week. swap them out next weekend and see what happens. rather or not they have any effect im going to rip the generator and intake manifold off and change the gaskets from the metal type to paper with the copper spray stuff. i might even lap the manifold end castings just for good measure. swap over to the alternator and pray like hell that maybe there was some kind of vacuum leak i haven't been able to pinpoint.

after that idk, maybe say the hell with it and redo the seats like i wanted to a year ago. at least then ill be comfortable while cranking the ignition over for no reason :lol:
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Super_Randy
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Re: the never ending project. 71 super build

DR7EA spark plugs acquired. we'll see if it makes any difference.
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Super_Randy
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Re: the never ending project. 71 super build

new plugs are in, car wont start. just backfires out the carb when you crank and crank and crank and crank and crank and crank it.


edit: alright, i got pissed, gave up, and pulled it all apart. generator and stand are off, intake manifold and carb are off. and low and behold there was fuel all over between the manifolds and heads so its pretty obvious they were leaking. getting the 3/4 side off was a bitch. one of the the nuts is almost impossible to get to with the engine in the car. idk how im going to get it back on... so the plan is now to lap the manifold ends and swap to paper gaskets with copper spray sealer. pressure test the center section cause why not. put it all back together with the alternator. and if that doesn't work, idk, buy a Chevelle and twin turbo LS swap it i guess. :?
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