64 stalls when taking off

[Daniel Riseborough]

Hey guys new thunderbird owner here from the UK.
Any tips would be much appreciated
Just bought a 64 thunderbird here and I'm have problems driving away sometimes.
Its starts slow but when I get past 25 then if flies away
Why is that, do I need to let the engine warm up first or am I putting too much gas or not enough gas. I also live in a hilly area might that be a factor.
Thanks...

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[Hadderz]

Hi, I'm in the UK too - Welcome to the club!!
From your description it is carb related, could be the choke not working correctly or even float levels. Do you know what carb is fitted? From your pictures it's not the original air cleaner and shows Edelbrock suggesting one of those???

 

[57tbird57]

Hey guys new thunderbird owner here from the UK.
Any tips would be much appreciated
Just bought a 64 thunderbird here and I'm have problems driving away sometimes.
Its starts slow but when I get past 25 then if flies away
Why is that, do I need to let the engine warm up first or am I putting too much gas or not enough gas. I also live in a hilly area might that be a factor.
Thanks...

Sounds like the carb is running a little lean. May need an adjustment or rebuild. Good luck with your new to you bird

 

[iwinyouwin]

A couple of thoughts...
1. Are you starting in the correct gear? You need to go from Park to Reverse to Neutral to Drive 1 and use Drive 2. Drive 1 actually starts out in second gear - was intended to help with slippery roads I think.
2. I you were driving and stopped with engine off for a very short time you could be getting some vapor lock when you start going again

 

[Daniel Riseborough]

Hi iwinyouwin
So when I'm driving I start in part obviously then gear through into the dark drive spot not the white
So I've been driving in the wrong circle and should be the white one Isit.

 

[Hadderz]

A couple of thoughts...
1. Are you starting in the correct gear? You need to go from Park to Reverse to Neutral to Drive 1 and use Drive 2. Drive 1 actually starts out in second gear - was intended to help with slippery roads I think.
2. I you were driving and stopped with engine off for a very short time you could be getting some vapor lock when you start going again

So is that the green dot which is just after neutral or do you go straight down to the last position to move off then back up to the green dot?

 

[Daniel Riseborough]

Yeah I go off on the green dot after neutral
And that's when I can sometimes take off and sometimes stall
Am I supposed to be taking off on the white dot?????

 

[64ZCODE]

sounds like the accelerator pump isn't doing its job, which is to add a big squirt of gas into the carb when you mash on the pedal. if you have a hesitation at midrange acceleration, it could be the power valve assuming your carb has one.

i've found that my '64 accelerates fine when taking off in second. actually first seems almost like a throwaway since it shifts from first to second at around 8 mph.

 

[Olympus 200]

Yeah I go off on the green dot after neutral
And that's when I can sometimes take off and sometimes stall
Am I supposed to be taking off on the white dot?????

Hi

When you say stall is the engine actually cutting out? I've just installed a reconditioned engine with a new Holley 4160 600 cfm carb in my '65. The engine has now stopped on two occasions in similar circumstances in the last 200 miles: pulling away normally (not flooring it) at about 15-20 mph having slowed down for traffic lights or a roundabout. slight backfire through the carb and engine stopped. Started OK on the key both times. Had replaced 0.31 accel jets after the first incident with 0.35s, doesn't seem to have cured the problem. Hate intermittent faults.

Cheers

Clive Rogers

'65 HT (Somerset UK)

PS You are not alone.

 

[64ZCODE]

Hello Clive. It does sound like fuel delivery/carburetion versus an electrical issue. In the carb, could be the accelerator pump or sticking float or perhaps a defective power valve, all of which seems unlikely since the carb is new. I'm wondering about your fuel pump too. When I first got my '64, the fuel pump was dodgy. The car would die and refuse to start, then after a while it would start. Turned out the fuel pump was failing intermittently.

 

[mr4speed]

You know it couldn't hurt to spray the carb a little to clean those small openings and clean up the carb. I would also suggest adding a good amount of fuel and carb cleaner in the gas ( petrol for you guy's). I have a 1966 Bird with the "Q" code 428 , man does it ever cruise. Wish I could take you for a ride, Greg

 

[Daniel Riseborough]

Hey all I now that I've had the car 2 months. When I turn the car on, I leave it a minute before taking off revving a few times to get that fuel pumping through.
I find I take off on L gear and as long as don't floor it I haven't had any more problems stalling. And I get to around 15 to 20 before I start hitting the gas gradually.
Doesn't like hills though.
But on a cold day it I just start and go withing 20 seconds it does engine stall.
And I normally put in half a bottle of engine fuel cleaner when I fill up the tank....

 

[Olympus 200]

Hello Clive. It does sound like fuel delivery/carburetion versus an electrical issue. In the carb, could be the accelerator pump or sticking float or perhaps a defective power valve, all of which seems unlikely since the carb is new. I'm wondering about your fuel pump too. When I first got my '64, the fuel pump was dodgy. The car would die and refuse to start, then after a while it would start. Turned out the fuel pump was failing intermittently.

Hope its not the fuel pump as that's new too. I'm going to try out a different accelerator pump cam as the next step. I have a spare 4160 carb I bought 15 years ago and had used on the old engine, .031 accel jet, orange cam, same as the new carb. That used to hesitate and sometimes cough on pulling away from standstill although it never actually stopped. I mitigated the problem by gently pumping the accelerator, resolving to fix the problem properly when the new engine when in . . .

Cheers

Clive Rogers

 

[Olympus 200]

Hello Clive. It does sound like fuel delivery/carburetion versus an electrical issue. In the carb, could be the accelerator pump or sticking float or perhaps a defective power valve, all of which seems unlikely since the carb is new. I'm wondering about your fuel pump too. When I first got my '64, the fuel pump was dodgy. The car would die and refuse to start, then after a while it would start. Turned out the fuel pump was failing intermittently.

Hi

Replaced the orange accel pump cam with blue, have done about 20 pullaways from 10-15 mph or less followed by a 20 mile trip and no problems so far. Hopefully the blue cam plus 0.35 accel jet have resolved the problem. By the way, I found the Holley website very informative.

Cheers

Clive Rogers

 

[64ZCODE]

Hi

Replaced the orange accel pump cam with blue, have done about 20 pullaways from 10-15 mph or less followed by a 20 mile trip and no problems so far. Hopefully the blue cam plus 0.35 accel jet have resolved the problem. By the way, I found the Holley website very informative.

Cheers

Clive Rogers

How is your idle mix? The best way to set it is with a manifold vacuum gauge, adjusting the idle mix screws in and out (equally) until you have maximum manifold vacuum. Holley covers this as a procedure here:

Here Is The Correct Procedure For Setting An Optimized Idle Mixture And Speed

Setting the idle mixture and speed on a carburetor isn't the most exciting or elegant subject, but it is a necessary adjustment that often is overlooked or worse, set up incorrectly. Here's the proper way to handle this basic task.

www.holley.com

It's surprising how much the idle mix can affect start up and runability.