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-   1st Generation Specific (1979-1985) (https://www.rx7club.com/1st-generation-specific-1979-1985-18/)
-   -   weber owners: how do you start you car? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/weber-owners-how-do-you-start-you-car-266239/)

timmya2 01-30-04 01:09 AM

weber owners: how do you start you car?
 
no choke.. cold blooded carbs..

how do u guys manage every morning?



this is wat i used to do..



pump twice..

start... she no start..


i stop


pump another two times..

start while holding pedal a bit down.. like almost taping it..

then she fires up.. but revs jump to 3k!

i let go until it goes to around 1.5k where i leave it for 1 minute and then i let it off some more until it goes to 1k..


now.. lately that hasnt been working..


so now days.. i pump twice..


no start..


pump twice.. she no start.. ( i think im pressing too hard)


i lift bonnet.. and manually nudge on the throttle to make sure strong squirts of fuel are in the carb..

then i start without pressing the pedal.. and she fires right up..


but then the revs are low like she almost wants to die.. so then i quickly press the gas to around 1.5k to prevent her from dying.. until the revs idle at around 1k..




end of story

Gregs 01-30-04 01:19 AM

hey timmy, do you have a choke on yer carb?

-greg

Gregs 01-30-04 01:20 AM

with my new engine i dont even have to pump it
i pull the choke out hafl way and crank and the bitch fires right up , today it was about 40 degrees and it fired right up without a tap of the gas :)

timmya2 01-30-04 01:27 AM

awsome!


nah i thought weber 48idas didnt have chokes?

Gregs 01-30-04 01:47 AM

i wasent sure, ive never used a weber

-greg

Quick SP 01-30-04 01:50 AM

the reason you have to pump the throttle is that you need to get the fuel into the engine but you also need to get the inside of the intake wet enought to keep the motor running.what size of jets do you have for ide.what size venturies are in the carb,and what motor,any porting,it all plays a part in tuning

timmya2 01-30-04 02:25 AM

ic..


hmm it could be the venturis..

my venturis are bigger than 40mm..

no porting yet..

not even an exhaust yet..
everything is stock
my cusotm exhaust only fits on a manual gearbox. because it hits the auto one..



so im saving up for a 5 speed swap.. before i put the exhaust in..

deeman111 01-30-04 05:36 AM

how i start my 48ida on my 12a bridgeportthat hasnt been tuned yet (still running it in)

pump twice
start while bouncing pedl to abour 1/4 throttle

usually starts
if not i do it again and it starts, then i hold it at 1500-2000 for warm up, then she idles at 2000 on her own... on cold it will idle very rogh at 1000rpm

Ill let you know what its like when i get it tuned and jetted right

-James

timmya2 01-30-04 07:49 AM

ok kewl..

Tom93R1 01-30-04 08:43 AM

My REPU has a 48 DCOE. I pump 5-6 times then crank without touching the pedal, fires right up. As soon as it gets running I have to flutter the pedal for a couple seconds to keep it going then it is good. When it got really cold (when I lived in Colorado) I would wrap a plastic bag around it to simulate a choke.

rx7gen2 02-24-04 01:26 AM

Turn on ignition so the fuel pump can fill the float bowl......wait ten seconds.....pump twice (long strokes)....crank engine. I might have to feather it for about half minute until he idles on her own.

Have you checked your idle tuning lately?

REVHED 02-24-04 02:29 AM

Well, usually I start my car by turning the key. :D

Sorry timmy, I couldn't help it. ;) But seriously, I bet you're flooding it. Try starting it without pumping the throttle at all. Mine always started with no pumping and just slightly giving it a bit of throttle when you turn the key. The fact that you need to give it throttle to stop it from dying also indicates it's probably flooding.

QuagmireMan 02-24-04 05:31 PM

mine starts right up.... i started it when it was 20 out.. the main problem i have with my holley fuel pump is when i shut it down, it floods my engine.

DriveFast7 02-24-04 08:10 PM


Originally posted by QuagmireMan
mine starts right up.... i started it when it was 20 out.. the main problem i have with my holley fuel pump is when i shut it down, it floods my engine.
What fuel pressure regulator do you have and what PSI is it set too?

I have seen fuel pressures set way too high on some carbs. so high that you shut motor off and excessive pressure in the fuel line will push fuel and overwhelm the needle and seat; fill float bowl and have gas forced thru the auxiliary venturi and into the motor. FLOODED.

My 12a Jbridge with Dellorto 48dhla and 42mm chokes uses 2.25psi on it's Holley 110gph fuel pump. I can floor it down the long front straightaway @ Buttonwillow RAceway Park (~1/2 mile) shifting @ 9400rpms all the way into 5th gear and not have it run lean.

Also seen a guys Mikuni set to 4.5psi "because that's the pressure everyone says to run" with air filter off see fuel being pushed thru aux venturi and dripping out of the velocity stacks.

Siraniko 02-24-04 08:28 PM

As long as the float is properly set, you shouldnt have a problem regardless of the fuel pressure. its true that the recommended or desireable pressure on an IDA is 4.5. However, it find that inaccurate.

I have a 48 IDA in my RX-3 and FB. Both have the carter 7psi f/p with fuel pressure set a 6si at WOT. Venturies 43, idle jet 75. No flooding problem and no problem starting it in cold mornings. After many years using IDA, I came up with this process.

Turn the key to ON to get gas in the fuel bowl.
After 5 seconds, turn OFF, pump the pedal 5x, then start. No need to keep my foot in the gas pedal. It will bog slightly but it wont die. BTW, my idle is set at 1K RPM.

heb09 02-25-04 05:28 AM

turn key, give bit of gas, fires up and sits at about 800rpm for a minute or so


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