stingraymaniac

i have a holley 650dp in my car.
sometimes it just starts to go really bad.
its spits and backfires and i loose the idle
stuck float?
ore is there some dirt in it?
but when it runs it runs great!
has happened four times in the 2 years i have owned it
also it has no idle when its cold is that just the idle mixture that is wrong?
where do i adjust that?
not so familiar with hollley carbs..
thanx for every answer!!
:smash: :smash:

stingraymaniac

anyone?

R. Bruno

QUOTE]i have a holley 650dp in my car.
sometimes it just starts to go really bad.
its spits and backfires and i loose the idle
stuck float?
ore is there some dirt in it?
but when it runs it runs great!
has happened four times in the 2 years i have owned it
also it has no idle when its cold is that just the idle mixture that is wrong?
where do i adjust that?
not so familiar with hollley carbs..
thanx for every answer!!
:smash: :smash: [/QUOTE]

I assume you have checked that the choke is operating correctly? If it is not, it would not run well cold and if it is sticking open when the car is warm, it would cause the problem you describe. It could also be a combination of the choke and something else.


[Modified by R. Bruno, 2:54 PM 4/11/2004]

stingraymaniac

the carb has a manual choke it is not connected
how much open shall the choke plate be to not have any choke?

R. Bruno

No choke definately = problems at cold start. I would also think that without any cable at all, the choke flap may close from time to time when you are driving and cause the problem you are describing. Is the choke completely loose? I mean is it connected to anything or just flapping away at will? It shouldn't be this way. It should be wide open when the motor is warm and stay that way. When cold it should be almost closed but not completely. (maybe a 1/4 or 1/8 of an inch from closed) You need to hook up that choke cable and play with it a little before you start adjusting other stuff Just my .02, :cheers:

verskel

IF you're not planning on using the choke - wire the darn thing wide open & setup the carb. to compensate for cold starts. This means, you'll be running rich and will have to 'force' the car to run by pressing the gas pedal slightly for about 1-2min. until it'll idle. You'll also need to increase the idle adjustment.

It can be done although it's not as civilized. :yesnod:

stingraymaniac

i have it stuck wide open,but the owner before had it loose the car wasnt driveable sometimes then i took the air filter off and discovered the choke was completely closed... :crazy:
but thats not my problem now its something else... :smash:

Solid LT1

There are lots of potential causes to bad idles but, you should change the power valve if you have had a severe backfire during operation. The power vave is a vacuum operated enrichment device that can be torn by high pressures during an engine backfire. The result will be an inconsistant fuel curve that will be very rich! You need to buy one of the many good books on Holley carburetors that can be found to learn how this equipment works to keep it in a top state of tune and to diagnose problems. The power valve is cheap enough to replace that you should go ahead and do it. I just thought of one other potential problem that can happen: your rear accelerator pump linkage can be contacting the air cleaner tube to the valve cover PCV hose if you are running a stock AC Corvette chrome air cleaner causing and intermittant secondary pump discharge. The accelerator pump linkage can be "tweaked" to give you clearance from the elbow to the linkage, be sure and check that you do not bottom the accelerator pump diaphram after checking for proper operation when finished.