1967 Supreme
I have to pump the pedal 10-15 times to start.
It starts up a very high rpm.After about 5 minutes I pump the gas
and it lowers rpm.Another 5 minutes I pump again,and it idles beautiful.
Why so high at first? Why so long to calm down?

 

There's a high-idle cam, actuated by the choke, that needs adjustment!
The pumping while cold is typical Q-jet leakdown, on old carbs.
A rebuilt will correct it!

 

What is the best rebuild kit?

 

Also Is this carb out of date for the 330 ?
Is there a better one?

 

It's called "warming up."

When you depress the pedal on a cold engine, it pushes the fast idle tang clear of the fast idle cam and allows the choke to set. The tang sits on the fast idle cam and raises the idle so that the car will not stall when started cold.

As the engine warms up, the choke slowly opens, and as it opens, it drops the fast idle cam, one step at a time, toward the normal position. The idle does not go down, though, until the pedal is depressed to lift the tang away from the cam and allow the cam to drop to the next step.

The amount of time it takes reflects the amount of time it takes the engine to warm up.

You need to check the manual and review the procedure for setting the fast idle, then check it, and reset it if it's too high.

"Q-jet leakdown?"
Unless there is something wrong with his carb., nothing is leaking anywhere.
His description sounds like completely normal operation to me.


Nothing is his description sounds like abnormal behavior.
His fast idle may be set high, then again, it may be dead on, but sound high to him. Even if his fast idle is high, that is no reason for a rebuild, just a twist of the screwdriver.

- Eric

 

Could be the eccelerator pump seal inside the carb may need to be replaced if it takes 10 - 15 pumps to get it going, in which case a carb kit would definitely do the trick. My 72 only needs 2 pumps to start. One to set the choke plate closed & give a shot of gas & the second just for an extra shot of gas. Starts right up after that.

 

There is a consistant problem with older Q-jets leaking-down overnight, as the well plugs are soldered in, and the solder fails!!
The cure for this, while you have it apart, is to get some 2-part epoxy, mix it up, and apply it on a clean surface! The well plugs are obvious!
I've probably used ten different brands of rebuild kits, and never had a problem.
Your choke may be set a bit tight. I usually set them open about 1/8 inch when cold with the 3 screws on the choke.
If the idle is too high, there is an adjustment on the fast idle cam!

 

if it's a 1967 qj, it's quite possible that the secondary well plugs are leaking(leakdown) because they are simply o-ringed cup plugs. there is a fix available for that.
remove the air cleaner lid when the engine is cold, have somebody push the gas pedal down once while you watch the choke valve(don't crank the engine over). the choke valve should close fully, and positively on the first push down of the gas pedal(you could do this yourself by moving the throttle linkage). now, hold the choke valve open while looking straight down the primary barrels of the carb. and watch for 2 small streams of gas being squirted down the throttle bores. if you don't see them, either your float bowl is dry(leakdown) or your accelerator pump is defective.

if you do a rebuild, get a new float. if the vacuum break is original, replace it too.


bill

 

that is an incorrect adjustment.
at room temperature(~70 degrees) the choke should be set to fully close.


bill

 

The OP did not say how long the car has to sit before he needs to pump the gas that many times. Honestly, I've had a lot of cars that seemed to need that after sitting for several days, and it never bothered me at all. He may have leaky plugs or the fuel may be evaporating, or it may be leaking back through the fuel pump. All worth checking, but probably not worth the trouble if it's otherwise running well.

As for his other two lines of description, and the answers to his actual questions, which none of the other posters have responded to, I stick to my first post: It's normal.

- Eric

 

A side note.....
Epoxying the well plugs does work, but is only a temporary band aid solution to the well plug leak.
The fuel will eat the epoxy eventually, and the carb will have to come apart again.

To do it right you should remove the old plugs, bore and tap the housing, and use screw in type plugs.

 

I agree with Eric on fast idle being normal. One pump of the pedal should close the choke and set the fast idle cam. Once warmed up a bit, tap the pedal to slow the idle before taking off.

Having to pump the accelerator a bunch after sitting (days, not hours) is common if not correct. Don't know if it's leakdown in the bowl, evaporation or the accelerator pump but more of an annoyance than problem if it runs OK otherwise. The SBC in my boat has a bad case of this.

 

What concerns me is the length of time he says it needs to idle down. That tells me the choke itself may be adjusted correctly, but that the choke thermostat coil may be weak or the hot gas crossover passage in the intake is plugged.

I go thru this regularly with the wagon if it's sat a few days. Try spinning the engine over a few seconds first without doing anything with the pedal, then pump the pedal a couple times to set the choke and prime the carb with fuel. If the Q-Jet has leaked down or evaporated (thank you modern fuels) dry, this gives the fuel pump a chance to put some fuel to the carb bowl.

If it's taking more than a minute to idle down, there's something going on with the choke heating system. Either a weak choke coil or a plugged heat crossover.

General rule of thumb on choke idle speeds: no more than 1500 RPM fast idle with cold engine, choke on, and pull-off set to open the choke plate 1/8" or so. Unless it's extremely cold, say down in the teens or lower, car should be completely off fast idle within 2 minutes.

 

from a cold start,if the choke rod and vacuum break adjustments have been done correctly, a foot tap should take the car off of the highest step of the fast idle cam, which will reduce the idle speed some. at that point, it's up to the choke coil and heating system to reduce the idle speed to curb idle(after another foot tap). most fast idle cams on qj's have 3 steps, there are some that have 5 steps. without being there to see what is going on with your car, i will join the others and say it's likely normal operation that you're experiencing.


bill

 

Hey Doctor
Once it warms up.It will start with a couple cranks.But everyday (the first time)I have to pump 10-15 times to start.

 

I agree that if it needs ten pumps to start after sitting for less than 24 hours on a not-too-cold day (you're in Tenn.), then something isn't right.

As others said, bad accel. pump rubber (would cause inadequate volume, but would also cause hesitation on acceleration) or leakage, whether through bad plugs, cracks, or otherwise (would probably create a constant gas smell) could be the cause.
I would say that one day is too short a time for evaporation or fuel pump backflow.

A rebuild would be a cheap and reasonable way to fix it.

Of course, if it's running GREAT otherwise, for the love of Pete leave it alone and just accept the pumping.
I avoid rocking the boat when all is otherwise well.

- Eric

 

Except you're thinning the oil every night, maybe a pint at a time!
Check your oil a week after changing it - you'll see for yourself!

 

Does the 67 have a paper fuel filter in the carburetor and if so does the filter have an anti-siphon valve?

 

If you pull the air cleaner off in the morning and pump the throttle are you getting two solid streams of fuel on the first pump or second pump? If you watch your choke operation from a cold start to warm up, is it operating as the others describe?

I find in some of these cases it could be an ignition problem, which some mistake for a carb issue.