1964 Fury, shaking and wants to stall at stop light, but idles well in neutral and drives smooth

[Evan Frucht]

I have a 64 fury wagon
transmission has been rebuilt this year.
Engine runs strong and passes all the general tests. Creates good vacuum. Timing is set at 15/TDP. Idle is set to 530 rpm using timing light. Did best to tune the CARTER AFB using the method where you turn mix screws in until it starts to die and then back out till highest idle. Then adjust idle down to spec.
Just got the brakes completely overhauled and am driving it around. The main issue in having it that is shakes and vibrates when the trans in DRIVE and I'm at a stop with the brakes on. The idle also slows down and gets rough. If I put it in NUETRAL this completely goes away. It also goes away once I take off and when I'm driving at any speed. It's just as soon as hit the brakes and come to a stop.

It does NOT make any clunk sound when putting it in drive. Also had someone shift it into D and R with the parking brake on while I watched and the engine didn't move around much or anything.

I know for a fact the front suspension needs to be rebuilt but it drives OK even given the worn out suspension ...

I rebuilt the carb recently. I'm pretty confident there is no debris in it but I don't know exactly what the inside of the gas tank looks like and there is some bits of sediment in my fuel filter so as a last resort I could look more into the carb.

Based on these facts does anyone have any ideas?
It is a project car I don't expect to get it perfect but something doesn't feel right when its stopped and in drive at the same time.

 

[dadsbee]

Turn the idle up.. it's too low.

 

[Evan Frucht]

Turn the idle up.. it's too low.

Ok I put it to 530 because in my original service manual it said for a 318 with auto that idle was set to 500 in the specs. It also said 700 as a "fast idle" but I noticed when rebuilding my car the fast idle linkage was damaged so I simply removed it. I figured its warm all year round here so I can warm it up quick enough myself. Maybe it was a bad idea to remove the fast idle linkage I'm not sure

What's a good idle speed to set it to ? I have a timing light so I can dial it in

 

[5.7 hemi]

I’d be around 7-750.

 

[493 Mike]

Power brakes? Maybe a leaky booster?
Mike

 

[Evan Frucht]

Its boosted. But literally got it back from Dewey last week so it shouldn't leak, at least I hope! There no vacuum leaks I think. It idles really well in NEUTRAL, just not in drive with the brakes on.

 

[493 Mike]

Its boosted. But literally got it back from Dewey last week so it shouldn't leak, at least I hope!

Throw a vacuum gauge on it.
Mike

 

[Evan Frucht]

On the booster or intake? What should I check for ? What reading . Things to look out for?

 

[Evan Frucht]

I put a vacuum gauge on the intake, my gauge might not be working quite right or maybe the idle was set to low when I did it, but the needle was jumping around. It did read like 20-30 psi vacuum tho.

This was before I hooked up the booster

 

[beanhead]

If it's fluctuating from 20 to 30? That's a red flag...put it in gear and E-brake/block the wheels or have a helper hold the brakes so you can experiment with the in-gear idle speed. If it still acts up at the higher idle start hunting for leaks...

 

[Evan Frucht]

If it's fluctuating from 20 to 30? That's a red flag...put it in gear and E-brake/block the wheels or have a helper hold the brakes so you can experiment with the in-gear idle speed. If it still acts up at the higher idle start hunting for leaks...

Ya it was fluctuating, but the car might not of been 100% warn and also the idle was too low when I was testing it as I'm figuring. I'll do a better test tmrw.

So I should tune the carburator while its stationary in gear vs in neutral ? Or not necessarily?

ALSO, couple basic questions:
should I set the idle speed to 700 while it's in DRIVE? Also should the idle speed change at all when I shift from N to D?

 

[beanhead]

I set idle in 'D' and let the neutral idle speed fall where it may. If things are tuned and working together it's only about a 100rpm difference (on mine). Idle Rpm depends on your cam and overall setup, 650-750 in drive should be okay if it's not too wild..

 

[Evan Frucht]

I set idle in 'D' and let the neutral idle speed fall where it may. If things are tuned and working together it's only about a 100rpm difference (on mine). Idle Rpm depends on your cam and overall setup, 650-750 in drive should be okay if it's not too wild..

Previous owner told me the cam had a mild re-grind, but who knows what they did to it. I'll tune in drive tmrw thanks for the help

 

[khryslerkid]

Previous owner told me the cam had a mild re-grind, but who knows what they did to it. I'll tune in drive tmrw thanks for the help

I think Beanhead was just talking about adjusting the idle speed while it's in gear.

Personally I wouldn't chance doing anything under the hood while it's in gear. Adjust the idle in park, place it in gear and see how it acts. Adjust again until it suits you.

 

[Evan Frucht]

I think Beanhead was just talking about adjusting the idle speed while it's in gear.

Personally I wouldn't chance doing anything under the hood while it's in gear. Adjust the idle in park, place it in gear and see how it acts. Adjust again until it suits you.

Ok thanks for the advice I'll try to just adjust the idle higher in neutral (750) and see where that gets me. I'm thinking If it still doesn't feel right after that, then I may have another problem.

 

[Big Bad Dad]

So you have a 50 year old carburetor that was engineered and has worked for everyone for all that time. And yet you just take off part of the control linkage and throw it away? And now it does not idle properly? Ya might want to re-think that part...

 

[493 Mike]

Also remember today's fuel is not what the car was designed to operate with and adjustments will be needed.
Mike

 

[KENTON]

Might have your idle screws a tad lean, try another 1/2 turn out.

 

[Bill Monk]

Everyone is steering you right. Tuning is a trial of patience. Test and tune, test and tune again until you get it right. Your timing sounds about right but every engine is different. Timing first, then carb. Using a vacuum gauge while adjusting the timing will tell you a lot. As already mentioned, you want to rule out vacuum leaks as well and check that fuel filter, if you can't blow through it easy, the pump can't pump through it easy but from what you described, I doubt that's your problem.

 

[Evan Frucht]

So you have a 50 year old carburetor that was engineered and has worked for everyone for all that time. And yet you just take off part of the control linkage and throw it away? And now it does not idle properly? Ya might want to re-think that part...

Ya when I bought it it wasn't working... The teeth, Or little notches on that part of it were damaged and worn down, it didn't work at all like it was meant to and would jump around when it shouldn't so I took it off until I can find a replacement. But then I wondered if I even needed it. I thought the fast idle was just to help it warm up with choke. My car starts fine. I blocked the heatcrossover too, but it only takes like 5 min to warm up to full temp just sitting and stays running even at low idle.

Can you explain why the removing the fast idle linkage might cause my specific problem. Does the fast idle do anything while driving around normally? would it go on at a stop light?