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Author Topic:   engine starting problem. HELP!
justin
Member
posted August 01, 2002 06:49 PM
My engine just started doing this today. What happens is that when I try to start the darn thing I have to put the pedal to the floor for it to fire off. It wasn't doing this a few days ago, it would start like a charm and nothing has been changed since then. I don't know if its a carb problem or ignition problem or what. The carb is a Holley QuikFuel 4412 with 73 jets. I'm running a DUI racing dist. set at 36 degrees total advance. I'm going to change my plug wires tomorrow because I've melted the boot on one of them, do ya'll think this could be the problem. Any ideas would sure be appreciated. Would like to get this straightened out before Saturday night if at all possible. Thanks in advance.

Justin

KPLugnut
Member
posted August 01, 2002 08:31 PM
The problem is likely to be in your carb. Check that the power valve is not blown or leaking, first. Your car has the symptoms of being flooded each time you start it and that's because the fuel is draining down into the intake (thereby flooding it).
The most common reason for fuel doing this in a carb is from a blown power valve that allows the fuel to fill the cavity in the main body behind the metering block, and then
to exit down into the intake thru the vacuum signal hole in the baseplate.
Check to see if the cavity in the main body is fuel soaked. There would be your problem.
Now, if it's not that, I'd still say it is in the carb. A quick rebuild should fix the problem, most times.
We've seen similar problems in other Quick Fuel 4412's in recent times, but that is not to say they don't do good work. All us carb shops have the occasional carb that makes us look bad..LOL!...

Hope ya find it, but if you're still stumped, get the carb to me, and I'll help ya out.

KPLugnut

Gene
Member
posted August 01, 2002 09:40 PM
I agree with lugnut. You might be getting a weak spark that will not fire a normally wet plug. But I'd guess the carb first,


racer2
Member
posted August 07, 2002 09:43 AM
I need help with a 800 holley double pump..
i can run the car with both ilde air screws all the way in,idles the fastest there,is there a fuel leak somewhere or what,other than that carb works fine,just started doing this.


KPLugnut
Member
posted August 08, 2002 07:58 AM
Racer2,
What size are the bypass holes in the butterflies? Or are there even any holes drilled in either the primary or secondary butterflies?
Also, take a look at how far open your primary butterflies are sitting when at idle.
If more than about .040" of the idle transfer slot is exposed (when looking from underneath the carb), then you aren't even using the idle circuit for the most part and therefore the idle mixture screws won't do anything (which seems like what you're saying is going on).
Start by drilling about a .090" hole in each
primary butterfly (anything up to .125" will be the most common needed size), then adjust the fast idle "skrew" so the butterflies are only exposing about .030" of the idle transfer slot. Then adjust your idle mixture screws to about 1 1/4 turns out from lightly seated.
Fire the car up and hook up a vacuum guage to read straight manifold vacuum. Then fine tune the mixture screws so that you get the vacuum guage to read the highest vacuum you can. First do one side, then the other.
In a nutshell, this is the quickest way to get the idle circuit in the ballpark.

Hope that helps,
KPLugnut

[This message has been edited by KPLugnut (edited August 08, 2002).]

racer2
Member
posted August 08, 2002 08:28 AM
thanks kp


awkwardjeff
Member
posted August 11, 2002 12:28 AM
The title for this subject caught me eye because I was having the same problem this week.......we ran two nights and both nights I needed to pour gas into the carb to get the motor to fire, every time all night, before each and every race I needed to gas the carb, we run meth. It was acting like it was loaded up with fuel, so after the first night I went through the carb and didn't find anything but did replace everything and the carb only has 6 nights since new.

After the 2nd night, I thought MAYBE it was inside the motor.......collapsed piston, bent valve, lobe off the cam or some other thing not allowing the motor to pull enough fuel, even though the motor didn't have a miss once it was running........after I poured gas and the motor would start it ran perfect, and pulled with the best of them..........that threw me off a little.......tonight I leaked all the cylinders, every cylinder leaked less than 3 percent and the motor has 57 showes since I built it and I have never had it apart. The next thing I did was pull the cap and rotor.............when I pulled the cap, oil started running out of the dist......I'm not kidding.......roflmao. I NEVER seen that before.......but I think I found the reason for the hard starting.

kplungnut, you give very sound advice.... thanks for your input.

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