Author Topic: Engine stalls out when braking hard  (Read 2097 times)

Offline Matt1968

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Engine stalls out when braking hard
« on: August 16, 2015, 11:00:43 PM »
Was doing some brake testing and I experienced engine stalling.  What is going on with the carb that would cause this?

Offline svo2scj

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Re: Engine stalls out when braking hard
« Reply #1 on: August 16, 2015, 11:16:02 PM »
If the car has power brake booster I would check for leaks at the valve, hose and booster.    I assume "braking hard" means off while off the gas.    If the car can recover from acceleration and idle without braking (read coast to a stop)  then anything bad in the vacuum area will show up just sitting still.  (brakes applied)

Mark
1969 R Code , Sportsroof (non Mach) W Axle
AB , Standard Interior  San Jose built 4/22/1969

Offline svo2scj

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Re: Engine stalls out when braking hard
« Reply #2 on: August 16, 2015, 11:24:20 PM »
Matt

Does this mean that you got the car running AND fixed the clutch???   Went back and re read all of your posts - was tring to see if car is a PB car.

Mark
P.S.  Amazing how time flies - Woodward is over , girls go back to college this week and I get two of my garage spaces back (from stored dorm rooms) !
1969 R Code , Sportsroof (non Mach) W Axle
AB , Standard Interior  San Jose built 4/22/1969

Offline Matt1968

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Re: Engine stalls out when braking hard
« Reply #3 on: August 17, 2015, 12:13:33 AM »
Hi Svo,  yesterday I got back to the project ,  put a new gas tank in,  flushed the line ,  took off the left valve cover to check things out.  Next thing I know,  its running perfect.  This is not the first time this car has mystified me regarding an electrical misfire with this engine.  Regarding the clutch,  when I parked it 3 years ago it was slipping badly,  nearly undriveable.  Now,  even though the pedal action is really bad, it gripping and drivable.  I just don't get it. 

Brakes are feeling weird so testing,  hard braking tests from 30mph,  engine stalls.   Thinking the power booster might be bad. 

Offline suskeenwiske

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Re: Engine stalls out when braking hard
« Reply #4 on: August 17, 2015, 12:41:13 AM »
There may also be what's called a Dashpot that is missing, maladjusted or possibly damaged. It's designed to allow the accelerator to ease back slowly when letting off of the gas, thereby preventing the engine from dying. Six and eight cylinder versions are different but perform the same function.

Ray
Ray
1965 Dearborn Coupe
6 Cylinder, AT, PB, PS, AC
Est. Build 23A

Offline Matt1968

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Re: Engine stalls out when braking hard
« Reply #5 on: August 17, 2015, 12:44:06 AM »
There may also be what's called a Dashpot that is missing, maladjusted or possibly damaged. It's designed to allow the accelerator to ease back slowly when letting off of the gas, thereby preventing the engine from dying. Six and eight cylinder versions are different but perform the same function.

Ray

I thought a dashpot was for a/c cars.....no dashpot on my car

Offline Richard P.

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Re: Engine stalls out when braking hard
« Reply #6 on: August 17, 2015, 08:39:56 AM »
I thought a dashpot was for a/c cars.....no dashpot on my car

The dash pot was used on Mustangs equipped with automatic transmission.