[iac17042007]

hi all,
my rebuilt 289 is running great except for a flooding issue which i can't seem to find the cause of. sometimes when i start the car fuel will pour over the top of the carburretor (autolite 4100) sometimes it will start,i went for a drive and goes beautiful no flat spots then after about 40 mins i stopped at the lights same again fuel over the top engine stalled.it seems to happen only at idle and deacceleration, when cruising no problems.the carburrettor is a pony rebuild,the seats have been blown out,float levels checked and this never happened before my rebuild so it's really got me stumped. i checked my fuel pump and it is delivering about 6-7 psi (mechanical oem) is this too high for a 4100? any help would be much appreciated thank you
i was running stock cam and heads and inlet but now running comp 268H , AFR 165 heads and shelby hi-rise

[429ragtop]

That is to much pressure for a 4100, it probably blew the float / needle valve. Drop the bowl and manually raise and lower the float to see if it moves freely and shuts off the gas (closes the needle valve), repair as needed and install a regulator between the carb and fuel pump to bring the pressure down to about 5.5 psi.

[Ivy66GT]

The Ford fuel pressure spec for the mechanical pumps at idle is 4-6 psi and at speed its going to be higher. I doubt your pressure is a problem.

Sounds to me like you have a bad needle and/or seat in the float bowl(s). You get both ones new in a $17 rebuild kit from AutoZone. Likely you would pay as much or more just for the needles and seats and not get all the other gadgets in the bag.

[cindys_sn95]

ivy is right. and it could be just float adjustment/trash in needle and seat. do you have a good filter before the carb?

[tbunker]

I want to agree with them. My 4100 that I got from Pony, the Fuel/Air Mixture was cranked super rich and the floats were cranked wide open. I leaned out the fuel mixture & that helped some and now I am just waiting for some good weather to adjust the floats down. I too am having some fuel coming out of the carb. It's bleeding out the fuel bowl vents.

So maybe take a look at those things.

[iac17042007]

hi thanks for all your advice, i took back to mechanic (he's been good until now)he fitted fuel pressure regulator to 4.5 psi claims needles and seats are all fine as is float level,new filters drove again this morning at various throttle openings and idle after about 20 mins got home and guess what it did it again fuel everywhere!! i am really over it might just go and get a holley as being in australia dealing with pony carbs is going to be impossible,maybe lowering float levels might help i just don't know what else to do other than replace the carb(it's been great until know though).

[tbunker]

Did he remove the airhorn (top of the carb)? That's the only way he would have been able to check the floats. I suggest that maybe you should check the floats yourself if you know how too before you go changing out your carburetor.

Do you own a Ford Shop Manual for your year of car? That is something very useful to own if you don't.

But trust me, I know how you feel. I myself am getting ready to change out my Pony Carb.

[Ivy66GT]

Tony,

I hadn't noticed your location. Reading you had a Pony carb I assumed you were stateside. Its been 30 years since I was in Adelaide.

The pressure regulator proved that pressure isn't your problem. And no matter what your mechanic said, the only other thing that can be causing petrol to spill out of your carb is either the float or the valve needle and seat. The float level might be too high or the float might be sinking. If it sinks though its likely to stay there and that is not what you report. More likely its just a bad needle. They have a nylon(?) tip that deforms slightly to mate against the brass seat. Yours appears to work most of the time, but regularly overfills the bowl(s). Maybe something is not quite right and the float gets caught and stuck somehow?

My comment about AutoZone won't do you much good in OZ since they won't ship outside the USA except to members of our military. If you can't get parts from your mechanic, surely there is some place in SA you can buy parts for old Ford carbs? The needle, seat and float are a simple system and easy to replace. I agree, trying to deal with any company half way around the world will be difficult. If your car were in my driveway this would be an easy fix since the needed parts are only a few miles away. In yours, I don't know.

Almost surely, this is what you need: http://napaonline.com/MasterPages/NO...eedle+%26+Seat

Pony Carbs is just down the Interstate from me but I have had no dealing with them. You are not the first to report problems with their products which makes me wonder what they are doing.

[iac17042007]

hi thanks for the help,i still suspect float level but trying to find old Autolite parts is really difficult in Australia (in hindsight i shouldv'e realised this) so i will keep my Autolite for a fix later and i am going to fit a 600cfm Holley as these are common as muck down here and everybody keeps spares no problem. just a quick question if anybody knows, i am using autolite spark plugs p/no 3924 any idea what a bosch or champion equivalent is? thanks

[Ivy66GT]

Originally Posted by iac17042007

just a quick question if anybody knows, i am using autolite spark plugs p/no 3924 any idea what a bosch or champion equivalent is?

Although I can find a #3924 on-line I don't know how that compares to the Autolite #45 which is the US recommended plug for a stock 289 and, BTW, is a resistor plug unlike the originals. Autolite, sister company to US Fram, is in the cheap end of the market and doesn't sell any non-resistor plugs now although they don't like you to know that.

In a Motorcraft the 289 plug would be a BF42C, Bosch is a D8BC and NGK is a AP5FS. The latter two may be the only numbers that will be common for both us and you since Bosch and NGK are more international companies. Autolite/Fram is a completely different company in the US (owned by Honeywell last I checked) than in other parts of the world. Autolite hasn't had any connection to Ford since 1973.

[Ivy66GT]

If you suspect your Autolite problem is the float level that is extremely easy to fix: just pull off the top plate and bend the float tab. Being careful you can run the engine with the carb top off to see where the float level actually is then bend the float accordingly.

It would be a shame to buy another carb if fixing the one you have is simple.