now what,,,, fuel?

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Re: now what,,,, fuel?

Postby sportster96blk » Mon Apr 04, 2011 10:22 pm

well i sure would hate to rebuild a brand new regulator, i think I'm just going to make the them(jegs) send me a new one and see what happens. if that doesnt fix my problem I'm going to go fuel cell the cost is cheaper then paying someone to weld the tank and will have almost the same result. it just take my car further from stock but it already to late to become a purest now...lol :P :o :? :wink:
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Re: now what,,,, fuel?

Postby sportster96blk » Fri Apr 15, 2011 12:17 am

OK i replaced every thing,new regulator ,new fuel pump,fuel cell and all seems fine. car runs good except at a idle. the idle changes slightly with the turn on and off of my fans(two 10 inch radiator fans which draw 30amps )with the fans ,fuel pump and spark box it uses almost all the power with all the power accessories on volts drop down to about 12.5 engine struggles to idle . alt puts out 100amps im going to step up to a 140 amp alt and see if it will sovle the idle problem
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Re: now what,,,, fuel?

Postby Wizeguyrc » Fri Apr 15, 2011 7:55 am

How are your fans powered? Through the fuse panel or straight from the battery / alt. ?



Tracy
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Re: now what,,,, fuel?

Postby chevy art » Fri Apr 15, 2011 2:52 pm

george just putting a higher amp alternator may not solve your problem. most of the alternators(modern) put the high amps out at 3000 rpms and above. there are alternators made to put out lots of amps at around idle and a little above. just think about being stuck in traffic and at around idle, all your accessories are running and needing lots of amps and your regular alternator dont give it. look into the high output alternators(at low RPMS). you may still get by with a 100 amp one/ let us know how this works out for you art
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Re: now what,,,, fuel?

Postby sportster96blk » Sat Apr 16, 2011 2:25 am

well i put in the 140 amp alt but seem to have a big draw when i turn on the lights but the car does know seem too run a lot better. the fan and fuel pump both are run by there own relays which draw from both a battery source and a keyed source. the fan does draw a lot of amps maybe too many I'm going to recheck all my grounds . ive never seen a alt. that works like chevy art said where might i look for that....george
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Re: now what,,,, fuel?

Postby sportster96blk » Sun Apr 24, 2011 1:14 am

well Ive now put in a mechanical fuel pump to remove some of the amp draw at a idle.the car didn't idle well when all the stuff was on(fans,lights, ect)so now it at least it idles well but i still am drawing to many amps at idle i must find a fan set up that will move good air and not draw to much amps and still fit in front of the the radiator :rolleyes: will this ever stop and thing settle in to place.....it seem I'm never done :rolleyes: :lol:
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Re: now what,,,, fuel?

Postby Pedestrian » Sat Mar 23, 2013 4:07 pm

I know this is an old thread, but I ran into a similar issue with my alternator. I went with a 140 amp model and it would struggle to put out 12.5 v at idle with everything on. (everything = 30 amp fan, headlights, blower motor, and windshield wipers) The solution that worked for me was to go back and solder as many high amp connections as I could that were previously crimped. I soldered the ring terminals going to the alternator / battery / main fuse / fan relay / solenoid / etc. I didn't mess with the headlight connections, but it made a huge difference. My voltmeter now reads 14 v with everything on in hot weather. I've noticed high under hood temperatures can cause an alternator to put out lower voltages, so I like to test output on a hot day with the hood down for more realistic results. As an added bonus, the starter cranks better too. I hope this helps.
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Re: now what,,,, fuel?

Postby cjbiagi » Sat Mar 23, 2013 4:36 pm

It doesn't take much resistance to start dropping voltage on a 12 volt system. Connections need to be tight and clean including all grounds. You also may need to increase the size of the charge wire that goes from the alternator to the starter if you are going with that large of an alternator. Resistance increases with temperature and the more current draw on a wire the hotter it gets, not to mention that most of this wiring is already hot because it is in the engine compartment. It may also help to increase the size of the battery cables, I increased the size of my battery cables from the stock size ( I think it was either 6 or 4 gauge) to 2 gauge. I had them custom made with the original type side terminals and that was the largest wire that could be used with the factory molded type ends.
With all of the components you have running you should expect that the alternator is going to put quite a drag on the engine and load it down at idle. Most modern alternators will put out their rated output at a pretty low rpm, that what made them better than the old generators.
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Re: now what,,,, fuel?

Postby vegastre » Wed Apr 17, 2013 12:08 pm

including all grounds


Never underestimate the importance of Grounds. The H-body is pretty finicky about this. I have 4 block grounds and two major body grounds. And a half dozen or so chassis grounds.
Phil Kennedy~
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Re: now what,,,, fuel?

Postby sportster96blk » Wed Apr 17, 2013 5:32 pm

well this is a old post, i got past my electrical problems quite a while ago. first thing i did was move the battery to the back of the car and install bigger cables for everything and i did add 2 huge ground straps and got rid of the electrical fuel pump went mechanical this smooth out the idle and know the car seems to handle all electrical components well...plus i disconnected the amp-meter so i dont have to watch it ...lol.....but Ive been driving the car for a long time now and no problem.....george
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Re: now what,,,, fuel?

Postby cjbiagi » Wed Apr 17, 2013 6:49 pm

It basically boils down to this, first you have to have the correct components and they need to be wired correctly. This starts with assessing your current needs (amps) and then getting a alternator big enough to handle them. Then have everything wired correctly (through relays when necessary) with the proper terminals and wire size. As mentioned, it's easy to start to lose a tenth of a volt here and there through inadequate terminals and connections. Before long they start to add up. Then of course pay close attention to your ground connections, must be clean and tight and also be of the correct wire diameter. Upgrading the wire diameter is pretty much always a good thing. Starts with the battery cables, the charge wire going to the alternator, especially if you installed a much larger amp alternator, along with the wires to any high load accessory. If wires run close to the exhaust make sure you insulate them. This helps not only to protect the insulation but also to help keep the wire cool. Remember, heat equals resistance. Following these steps should alleviate most electrical issues.
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Re: now what,,,, fuel?

Postby rtm » Wed Apr 17, 2013 9:04 pm

my SUMMIT brand liquid filled fuel
gauge is very close to my carb inlet.
I found that as the engine heats up, so does the liquid in the gauge.
the ONLY accurate fuel pressure reading I get, is when I start the car, and the engine is still COLD.
I would have to isolate the pressure gauge from engine heat, or the fuel pressure at the gauge will drop with actual engine temperature rise.
I learned this the hard way, of course. :lol:

tell me if you find the same problem.
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Re: now what,,,, fuel?

Postby sportster96blk » Wed Apr 17, 2013 10:55 pm

take the little rubber stopper out of your guage and let the oil out.it doesnt need it and will give more accuret reading (unles you boil the fuel before it gets there then you wont ever get a good reading ) my fuel presure guage works great (no oil)its a summit guage too
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Re: now what,,,, fuel?

Postby firebird77clone » Sat May 04, 2013 2:34 pm

If you are going to cut up the tank to accommodate the fuel pump, wouldn't it be easier to change to an in- tank pump?

I read a tech article on pumps some time back, and the biggest points I retained are that external pumps must be located below tank level, pressure return lines will carry heat to the tank, and raise the fuel temperature significantly, and in - tank pumps solve all kinds of problems.
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