440 with 727 Automatic dies when stopped in Drive**UPDATE!**

[nge]

Hi guys,
this is probably a very basic engine question, but it is still giving me fits.  
My newly rebuilt 440 dies in drive after the engine get to operating temperature and the the brakes are on (car stopped) and the transmission is in drive.  (440 /727  in a 73 charger) I bumped up the idle a few times and it now dies if im in drive, stopped with foot on brake and the headlights are on.  I seem to remember being told to set the idle RPM with the engine at operating temp and all accesories on and running.
Does anyone have any advice on how to trouble shoot this problem?
Thanks
Vic

[bordin34]

I had a similar problem. It was tied to my timing and idle mixture. I am running a holley 670 on my 440.

[nge]

Thanks, I'm  looking into into both vacuum and idle based on your experience.
I appreciate your help!

[myk]

Checking vacuum for a possible leak or low vacuum condition is a good idea.  If you've got a leak somewhere you can mess with your idle speed, mixtures and timing all you want, and nothing will change...

[nge]

I checked all the obvious vacuum leak locations, nothing obvious.
The engine now dies in drive, brake applied, lights on, and AC running 
Any other possible vacuum leak locations other than hoses?
I'm off to check timing now
thanks
Vic

[PlainfieldCharger]

Brake booster diaphram?

[redmist]

It's possible your converted is not matched well enough with your camshaft.

[69wannabe]

Brake booster could be bad and causing the engine to stall. I had a jeep cj7 I built a 304 for a guy and swapped out the 6 cylinder that was in it and about a year later he brought it back saying it was stalling at redlights. I let it run here in the yard for a little bit and checked timing and the carb, even pulled the carb apart and checked it out. When I went to drive it the second I put my foot on the brake pedal it started to die, turns out the more pressure I put on the pedal the more it would try to die. New brake booster and it was good to go!!!

[myk]

Hmmm....could a lack of alternator output cause a car to die like this?

[BSB67]

Way too little information.

Is everything else about the idle perfect in neutral?  Should not drop more than a couple hundred rpm from neutral to drive.  Any wandering idle rpm in neutral?  When you rev it up, does the rpm drop right back to normal idle rpm and stay there?  What cam?  History on the converter?  when was it last used?

Hand over the carb at idle is the way I like to determine if there is a vacuum leak.  Place hand over the primaries to choke the motor.  If there is a vacuum leak, the rpm will rise slightly before the engine dies.  I can do it with my bare hand, but have been doing it for years.  There is a little technique in doing it as you need to quickly get a reasonable seal.  If it does not seem to work for you, try using a rag.

[BSB67]

Hmmm....could a lack of alternator output cause a car to die like this?

Should run off battery.  But with that said, I have heard of a couple instances that the Mopar ECU, or other ignition issue was the reason for similar problems. 

[nge]

I have been trying all of the above except for the brake booster.
Idles nicely in D until it reaches operating  temp.
Cam shaft is "supposed" to be close to stock (comp cams CRB 280H-10, PN 21-237-4)

Do I need to have the transmission in Drive and brakes applied to set the timing? Im going for 15BTDC (FSM says 10)

I'm still here fighting!

[b5blue]

Hmmm....could a lack of alternator output cause a car to die like this?

It can and will, I'd check Alt. output and voltage at the coil in park AND drive. Plug and plug wire condition also. When I switched to Firecore plug wires I immediately noticed a "stronger" idle that was much less effected by putting in gear. Later when I converted to the Denso 120amp Alt (60amp output capability @ idle.) I again found my ignition enjoyed getting full juice supplied under all conditions like idling with wipers, lights and defroster running on high.
   

[BSB67]

Hmmm....could a lack of alternator output cause a car to die like this?

It can and will, I'd check Alt. output and voltage at the coil in park AND drive. Plug and plug wire condition also. When I switched to Firecore plug wires I immediately noticed a "stronger" idle that was much less effected by putting in gear. Later when I converted to the Denso 120amp Alt (60amp output capability @ idle.) I again found my ignition enjoyed getting full juice supplied under all conditions like idling with wipers, lights and defroster running on high.
 

Really.  My car runs fine without the alternator for awhile.

[nge]

38 deg initial timing (Needs to be at 950 RPM and 15" HG to idle in N )....I think something is wrong with the way they hooked up the distributor?
This was supposed to be my wife's fair weather daily driver

[John_Kunkel]

38° initial timing !!!!!! Is that with the vacuum hooked up or not?

[BSB67]

38° initial timing !!!!!! Is that with the vacuum hooked up or not?

Something is not right.

To the OP, is the dist vacuum hooked up to full manifold vacuum or port vacuum.

Double check you timing in each of the following conditions:  1) neutral with vacuum, 2) Neutral without vacuum, 3) In gear with vacuum, and 4) in gear without vacuum.

[nge]

38 BTDC is with no vacuum.
port on carb is blocked off to check timing.
I'm going to speak with the builder tomorrow...I just dont know what to ask him other than are the timing marks correct and what the engine signal  compensates for transmission load

[nge]

I spoke with builder this afternoon.
he did set it to 36 deg BTDC to get it to idle.
I'm going ot find TDC myself and see if it is mismarked on the dampner.
he suspects the carb is too lean at idle.
engine is a 440 (30 over) with a comp cams 280H-10 cam.  Stock heads, crank, exhaust and intake. Carb is a new 625 cfm BG Street Demon (the kind that looks lina a thermoquad)

What I can gather from al my searching is that the brakes, lights and A/C put a load on the engine at idle.  These loads change the vacuum signal to the carb richens the mixture at idle.  The carb is either is not responding to the vacuum signal or the signal is incorrect (I am thinking of this correctly?)

The carb is 1 year old but it sat at the shop for 6 months, so that could be a factor.

[RECHRGD]

Just a thought on the simple side.  Same thing was happening to me a couple of years ago.  Turned out that the carb to intake gasket was faulty and leaking.....

[BSB67]

Just a thought on the simple side.  Same thing was happening to me a couple of years ago.  Turned out that the carb to intake gasket was faulty and leaking.....

He seems to have ruled out a vacuum leak.

[BSB67]

I spoke with builder this afternoon.
he did set it to 36 deg BTDC to get it to idle.
I'm going ot find TDC myself and see if it is mismarked on the dampner.
he suspects the carb is too lean at idle.
engine is a 440 (30 over) with a comp cams 280H-10 cam.  Stock heads, crank, exhaust and intake. Carb is a new 625 cfm BG Street Demon (the kind that looks lina a thermoquad)

What I can gather from al my searching is that the brakes, lights and A/C put a load on the engine at idle.  These loads change the vacuum signal to the carb richens the mixture at idle.  The carb is either is not responding to the vacuum signal or the signal is incorrect (I am thinking of this correctly?)

The carb is 1 year old but it sat at the shop for 6 months, so that could be a factor.

You've said a few concerning things in this message.  Hope he checked the bearing clearance.

Anyways, yes, the next step is probably to determine TDC.  Report back when that is done.

[nge]

I have 3 old vehicles...so I never rule out a vaccum leak!
they have bitten me far to often so I will recheck the gaskets.
I have some tools on order to get TDC, because I want to learn and see how to do it multiple way and to check myself.
but I got to ask, what else did i say that was concerning?

[BSB67]

.... what else did i say that was concerning?

The guy that built your motor did not check TDC to the balancer, and he gave the car to you with the initial at 36° without telling, figuring it out, or fixing it.

If you did the hand over carb test correctly as stated earlier and as you implied you did, then you don't have a vacuum leak.

[PlainfieldCharger]

Bad harmonic balancer? Slipped on the rubber?