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-   -   OK questiion on what might be wrong..... (https://www.racingjunk.com/forums/showthread.php?t=25117)

DirkaDirka 07-30-2009 11:24 AM

OK questiion on what might be wrong.....
 
I got a 84 Chevy 4x4 that i just put a sb 400 in with a 750cfm 4 barrel(i think that is what it is) Anyways, evertime i go to start it after sitting a day I have to spray starting fluid on the air filter. What could be the prob with the starting issue. Now the engine only has bout 5 miles on it. I didnt build it so I don tknow whats inside the motor. Also I know the engine might be fined tuned. Will it fix the starting prob once the fine tuning is done?? Any help is greatly apprieciated.

ARUSSELL 07-30-2009 11:47 AM

Check for fuel leaking from the accelerator pump

DirkaDirka 07-30-2009 11:57 AM

Im sorry I should have put this in there before. It has a brand new carb from Summit Racing. I didnt see any fuel on top of the engine or any miosture around the carb at all. i didnt see any moisture around the spacer block under the carb either.

shawnp 07-30-2009 02:02 PM

Timing????

DirkaDirka 07-30-2009 02:25 PM

Timing is good. I believe I set it around 10 degrees adv. It only does it for the first initial start. You can shut it off and start it right up after letting it sit for 2 hours. Its just got me a lil puzzled.

Tod74 07-30-2009 03:54 PM

Next time before you try to start it take the air cleaner off and pump the throttle and see if it has fuel. Maybe it's leaking into the engine while it sits or something. Or if it is a holley type carb just look in the float level sight hole and see. Just a thought.

johnracer 07-30-2009 04:02 PM

This is gonna sound kinda goofy, but I have to ask. Does it have a choke, and do you pump the throttle a couple of times before cranking cold? Many younger people haven't ever had to deal with cold starting an engine with a carb. They're used to just turning the key......

DirkaDirka 07-30-2009 06:29 PM

OK yes it does have a choke but it is electric and it is not hooked up. Yes I do pump the gas before trying to start it. I had a 70 ranchero and when it was cold outside I had to pump the gas 3 times before initial start up. Me personally I think that it might be losing fuel pressure somehow. I cant remember if it has a manual or electric fuel pump on it. The carb on it is a edelbrock 4bbl double pumper. It is set up so it will cont working in diff angles for cars with hydrualics and 4x4s. Im trying to think about everything I have tried. Would it do this if the floats aint set right?? or would that not matter? ALso to me there is no stupid or goofy question. The only stupid or goofy question is the ones not asked. Thanks for all your help. Keep the questions and suggestions coming. That way I can get this truck runnign right and good when I am home at the end of Oct.

cepx111 07-30-2009 08:53 PM

Unless it's cold where you live right now, it should easily crank with a few pumps of the throttle, even without a choke.

Otherwise do like Tod suggested.

After it sits a day or so and it won't crank, STOP and dont do anything else> remove air cleaner, look into the carb and move accelerator arm back and fourth a few times, if there is fuel in the bowl you should see gas squirting out of the accelerator pump nozzles, if you don't see fuel coming out of the nozzles the carb is empty and if that is the case all your doing by spraying the starter fluid on the air cleaner is giving the engine something to burn till the pump gets fuel back up to the carb.

If the bowl is empty - you either have a external or internal leak somewhere.
Visually look around the base of the carb and look for signs of dried fuel on the intake, it usually leaves a brownish to black residue. If it's internal, you'll have to remove the carb and see where it's leaking from.
It it were me and the carb is at fault , you said it was NEW from summit I'd send it back and get a replacement.

Goodluck, Cp

DirkaDirka 07-30-2009 09:49 PM

Thanks guys for the info. The sad thing is that is the second carb I put on it cuz I kinda broke one of the mounting holes on the first one. oopsy :oops: I will definitly try those things


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