What Could it BE!!!

[Anonymous]

So its been over three months ... in that time we have rebuilt the carberator (1940 Holley), new fuel filter, tightened linkage (two bolts on the firewall), checked the accelearator pump, and checked the transmission!!! Yet it still sputters and cuts off when the gas is pushed to the floor. WHY WHY WHY???? I am going crazy and do not understand why ... I've searched the forum for simliar cases and yet I still find nothing ... What else could it possible be .. the gas is spurting when gas pressed .... im convinced its not the carb??? Transmission mabey??? Everyone ... please read and help me ... anything would be appreciated ...


Thank You

Thomas

 

[mustang6]

Try advancing your timing a bit and see if it makes things better. I've found advanced timing helps deal with the gasoline shot from the accelerator pump. Sometimes it requires so much advance to overcome this condition that you run into other drivability issues though- hard starting, pinging, etc. If that's what you find then the best thing I've found is an MSD unit to allow you to back the advance back off but still overcome the stumbling.

 

[Anonymous]

mixed up vaccuum lines might cause this too....well, in a way, that is timing as the advance would be wrong...

 

[Anonymous]

I checked the timing with a timing light and it is perfect .... any other suggestions ... thank though ...

Thomas

 

[MustangSix]

I checked the timing with a timing light and it is perfect .... any other suggestions ... thank though ...

Thomas

It may "read" perfect, but still not be right. The damper may have slipped. And these engines tend to like a little more than stock advance anyway.

Try advancing it a few degrees to see what happens. More advance often helps with throttle response.

 

[buzzA4]

I was just gonna add the same thing Mustang6 said. Try setting the timing without the light. Use your ear and maybe a vacuum gage if there's one handy, but it's not necessary. You can set these things pretty close by ear.

Then use the timing light to see what the new "ear" setting is. If your balancer outer ring has slipped the timing mark will be out to lunch.

Just out of curiosity what is the setting you are using now?

Good luck, Buzz

 

[mustang6]

Yes, advancing beyond what's "perfect" according to OEM specs was my point. Stock initial timing is typically around 6 degrees BTDC, I find my engines run better around 12 degrees BTDC initial timing (assuming your dampner ring has not slipped), with higher vacuum readings and more ability to handle a stab of the throttle from an idle without stumbling.

 

[Anonymous]

Right now its set at 12 BTDC ... what is the damper ring ???

 

[PutPut6]

I set my timing by feel because the normal "stock" specifications felt sluggish and unresponsive. I'm running a tad over 25 degrees of initial advance, according to the dampener. I don't know if my dampener is slipped or not. I would try advancing the timing as much as you can as long as it doesn't ping on you. Is your vacuum advance working?

 

[Anonymous]

Mustang6 -

What are you using for ignition? Points or Pertronix or another aftermarket set up? I swear this sounds just like the problem I ran into a few months ago and I went through some of the same steps you do to overcome it. The others on this post may be correct but I would look to the cheapest alternatives in altering/replacing/modifying your ignition. I went back to basics and HAD new points put in (didn't both to try myself as I was so frustrated) and bodda-bing she drove (and still drives) like a champ.

Good Luck!!

Marvista66

 

[Anonymous]

Stock on my 66 Falcon I6 200 is 12° (alt-248). You are running 25°? My block only reads to 14°. How does yours read to 25°?

-Dan in Jensen Beach, FL

 

[PutPut6]

Stock on my 66 Falcon I6 200 is 12° (alt-248). You are running 25°? My block only reads to 14°. How does yours read to 25°?

-Dan in Jensen Beach, FL

I have a timing light with advance, so if I turn the dial on the light until the dampener mark moves to zero, that's the timing.

 

[buzzA4]

Right now its set at 12 BTDC ... what is the damper ring ???

The outer ring on the balancer/pulley on the end of the crank shaft. The TDC timing mark are on the outer ring. Which is connected to the inner ring by some kinda rubber stuff (not the correct technical terminology). As the rubber ages it can weaken and allow slippage between the inner ring which is keyed to the crank thus actual TDC and the outer ring which has the timing mark which will indicate TDC if there has been no slippage.

Just disregard the light and slippage . Tune by ear.don't matter. See what it gives you. Let us know.

12* with vacuum advance disconnected, worked beautifully for me when I was runnning all stock '66 200. Big improvement over the 6* stock spec.
My current setup is running a little higher about 14* without vacuum., 22* with vacuum, I think. I need one of them thar fancy adjustable timing lights.

Good liuck, Buzz

 

[Anonymous]

Ok ... so its been a long saturday moning ... let me start by thanking everyone for there time on this thread ... I have some good news and bad news ... good news .... problem found ... bad news ... how to fix???

So me and my dad took the spark plugs out to check compression and spark and found this ...


1 - 140 psi
2 - 125 psi
3 - 145 psi
4 - 160 psi
5 - 140 psi
6 - 175 psi

ok ... well that doesnt tell me much ... but wat does is the six foot stream of gas that blew out of my spark plug hole on number 6 .... wat???? thats right gas spurted out over the fender and on the ground of number 6 .... please help .. .ask questions ... help help ...


Thank You

Thomas

 

[Anonymous]

o yeah ... forgot to mention ... i just rebuilt the carb ONE month ago ....

 

[Anonymous]

if the #6 cyl;inder was full of gas it means that plug hasn't fired in a long time ( and the rings are pretty well seated). Instead of a lot of exotic diagnosis maybe you need to start with a basic tune-up. These cars do not have computers to monitor everything it all has to be done the old fashioned way. Points, plugs , dizzy cap, rotor button, plug wires (very often neglected), timing adjusted, check for proper vac advance operation, Double check firing order, Proper maintainence and adjustment is a must. A burnt $4 rotor button or an ill timing setting will cause as much problem as a burnt valve. Your compression readings while not optimal are certainly good enough for the car to run fine.

 

[JackFish]

I have had a plug become loose. That'll make yer engine shake a bit.
How long was the car sitting? Is the gas fresh?
(I know, I always ask that :roll: )

 

[Anonymous]

It hasnt been sitting ... my dad drove it to work on Friday ... the maintiance has been perfect so i feel that is not the problem .. any other suggesetions ...


Thomas

 

[durkzz8]

do you have the Pertronix unit. Myself and another user on this site have had problems with the engine only firing on 5 cylinders.

 

[Anonymous]

Petronix unit??? My engine is a stock 66' 200CI .... you tell me do i have one haha .... thanks yall for all ur help again ..


Thomas