Missing, shaking

[Viperpete 36]

17 hours ago, rutkak said:

There is some outstanding advice here.  To reiterate:

1).  Fix the choke.  Might need a choke stove or whatever they call it or get a carb with an electric choke.  I ran into this with a car that had headers - no provision for the hot air tube to go to the choke. 

2).  Find your timing marks and shoot for 12.  White out is your friend!  Great run down of procedures above to find TDC. 

3).  If you are running Pertronix make sure your coil is compatible.  It looks like a stock coil but I could be wrong.  Verify 12V although you are probably there with that new wiring.  Might need to add a relay if you are getting 6V during crank or run. 

4).  Tune carb with vacuum gauge. 

5).  And in all cases, check for vacuum leaks. 

Ken

I have thought about finding another 2 bbl carb with an electric choke. What do those go for? Thanks for the cliffs notes!

 

[barnett468 418]

6 minutes ago, Viperpete said:

 

The carb on your car is incorrect nut i would not buy one just yet as it may be just fine. I would check other things first. You should try adjusting the fuel mix screws on the front however but that process needs to be explained and i for one can't explain it until tonight.

[Viperpete 36]

OK so remember my car was shaking a lot, and took a long time to start? Well the issue was the carb! Not timing, not the harmonic balancer or any number of other suggestions. I bought a Holley 2 bbl carb from a member here. It was nearly new and I thought his price was fair so I bought it. I hooked it up and the car sputtered to life for a moment then died. Then id crank and crank and crank and it would sort of gurgle and then POOF turn off and blow fuel out the top of the carb!! WTF? wow I am not experienced with carbs. So I called my expert. My dad. He literally wrote the book on Mustangs and also engines- and a TON of other automotive material. So I told him what was going on with teh car and asked him to come over. Literally I mean literally within 5 minutes, of adjust this, turn this screw, back this screw a little bit, adjust this.... the car was running INCREDIBLY smooth! And literally would start with a single CLICK of the key! I mean holy ****, this thing starts faster than any of my FI cars. Instant ON! wow! I am so completely impressed with him right now. He said he hasn't messed with a carb since the mid 90's but I guess that when you learn how to ride a bicycle.....


All I can say is WOW and I am so thrilled with how much better the car drives. It feels like it has double the power, the throttle response is amazing, even the transmission seems to shift better. The only thing that is not 100% yet is the gas pedal is a lot harder to push down. I think I need a different spring or adjust the cable bracket a little bit.

Old Motorcraft carb:








Holley 350 cfm 2bbl

[barnett468 418]

Glad you got it going and that it was something simple and that you had someone that could look at it that knew a lot about cars. This is a good example of how it can be a bazillion times easier to diagnose a problem when one is actually in front of the vehicle instead of trying to do it by someones description of the problem. I and some others here also could have fixed it just as quickly and easily if we were there, so if you have another problem, it is always best to have someone knowledgeable like your dad seems to be, look at it if they are able to do so within the time you need it fixed.

 

 

[barnett468 418]

Where is the end of the hose going to that goes under the choke on the carb?

Your engine will also likely run better if you set the timing to the optimum level.

Your distributor vacuum advance is also ikely not providing the best amount of advance and if not, you can get an adjustable vacuum can and adjust it to the best setting.

Also, if your idle occasionally drops below it's normal level when you let off the throttle under some conditions, you ca fix that problem by installing a dash pot like the one that was on your old carb that wasn't working.

In addition to a different force of spring and/or different amount of spring preload being used, if the distance from where the cable and/or throttle spring connect on the new carb is different than the old ones, it will change the amount of force required to depress the pedal.

 

 

 

 

 

 

 

 

[Viperpete 36]

15 minutes ago, barnett468 said:

Where is the end of the hose going to that goes under the choke on the carb?

Your engine will also likely run better if you set the timing to the optimum level.

Your distributor vacuum advance is also ikely not providing the best amount of advance and if not, you can get an adjustable vacuum can and adjust it to the best setting.

Also, if your idle occasionally drops below it's normal level when you let off the throttle under some conditions, you ca fix that problem by installing a dash pot like the one that was on your old carb that wasn't working.

In addition to a different force of spring and/or different amount of spring preload being used, if the distance from where the cable and/or throttle spring connect on the new carb is different than the old ones, it will change the amount of force required to depress the pedal.

There is a tiny little vacuum line on the electric choke that is going to a distribution block of vacuum lines on the back of the intake.

The timing is what it is. I have rotated the dizzy slightly over the last couple of days and hear no pinging at WOT while driving.

Idle does not drop. I can rev the car and the idle drops quickly and accurately and does not "bog down" or have any trouble what soever.

My plan is to adjust the cable bracket and see if that makes a difference in the pedal feel

I will take a video of the car at idle, and revving so you can see how nicely the engine behaves now.

[barnett468 418]

The positive wire from the choke should be connected to the 9v post on the back of the alternator instead of the ignition providing it will fully open the choke within around 2 minutes.

Your engine can seem to run just fine but still not have the optimal amount of timing. Timing also involves the timing curve, nt just initial timing amd the timing curve can be changed some in a stock distributor. You cn also not have pinging if the advance is less more than optimal if your compression is low enough so just rotating the distributor and driving it to see if it pings is not the only way to determine if the timing is optimal etc.

.

 

[Viperpete 36]

34 minutes ago, barnett468 said:

The positive wire from the choke should be connected to the 9v post on the back of the alternator instead of the ignition providing it will fully open the choke within around 2 minutes.

Your engine can seem to run just fine but still not have the optimal amount of timing. Timing also involves the timing curve, nt just initial timing amd the timing curve can be changed some in a stock distributor. You cn also not have pinging if the advance is less more than optimal if your compression is low enough so just rotating the distributor and driving it to see if it pings is not the only way to determine if the timing is optimal etc.

I have a 1 wire alternator. Also an AAW wiring harness. I just wired the choke to a KEY ON 12v spare circuit.

The car is running really good. I am not really looking for optimal anything. I don't want to invest any more time/money in it honestly. I am saving up for the MTF parts and also the Jon kasse heads. Shits expensive!!!! I have spent roughly $4300 getting the car reliable.Tranny rebuild, new carb, new ignition system, rebuild 8" rear, dual exhaust, AAW harness, headlights and trim, rear brakes and lines, oil pump- gasket rear main seal, valve cover gaskets, fluids, 1 wire alternator, like 4 speedometer cables, front shocks and blinker/driving lights. I also found a reasonably priced set of magnum 500's and i LOVE the way the car looks.

I just want to drive the car for a while bone stockish until the Boss 429 project begins.

[1969_Mach1 333]

Great to hear it's running better.  Other than a little tidying up hear and there, the only thing I see from the pictures is the trans kick down rod is missing.  I am assuming it's a C4 trans.  Without the kickdown rod, the trans will not downshift when going wide open with the throttle.  Also, get a new throttle return spring.  That thing looks ready to fall off.  I wouldn't drive the car like that.  Use a double spring setup for more safety.

With the engine running better the intake manifold vacuum has changed, thus, the trans will shift differently.  If the trans shifts too early or too late under normal driving adjusting the vacuum modulator would help.

[Viperpete 36]

4 minutes ago, 1969_Mach1 said:

Great to hear it's running better.  Other than a little tidying up hear and there, the only thing I see from the pictures is the trans kick down rod is missing.  Also, get a new throttle return spring.  That thing looks ready to fall off.  I wouldn't drive the car like that.  Use a double spring setup for more safety.

What is the kickdown used for exactly? The car downshifts just fine when i give it gas....

Also what kind of spring would you recommend?

[1969_Mach1 333]

Is it a C4 or FMX trans?  I can only say in my experience, they will not downshift when opening the throttle.  The kick down rod on Fords usually only start operating at almost full throttle.  Like if you are doing 35 or 40 MPH or so and have to open the throttle all the way while getting on the freeway.  You'll have to drive it a while and pay attention to the shifting.  If sometimes it doesn't downshift when opening the throttle and it seems like it should, that's probably from the missing kick down rod.

This Holley brand spring setup works on mine.  But it's a 351W and Holley 4 barrel carb.  It's two springs, a smaller one inside the larger one.  Most parts stores have other brands of the same type of two spring setup.  Getting something the right length is the only trick.     https://www.summitracing.com/parts/hly-20-89/overview/

 

[Viperpete 36]

Tranny is a C4. It downshifts like a normal car without the kickdown. Don't know how though if you are saying that is a required part. Id say that it needs to see 1/2+ throttle to downshift.

I'll try fiddling with the bracket first then.

[RPM 1,190]

 Glad that it's running well. As mentioned the kick down rod down shifts when  accelerating and you floor it. The rod is not applicable when slowing and the trans downshifts.

[Viperpete 36]

17 minutes ago, RPM said:

 Glad that it's running well. As mentioned the kick down rod down shifts when  accelerating and you floor it. The rod is not applicable when slowing and the trans downshifts.

Yeah it does that without the kickdown. Downshifts when I give it gas. Surprised actually how crisp and fast the shifts are.

[barnett468 418]

5 hours ago, Viperpete said:

I have a 1 wire alternator. Also an AAW wiring harness. I just wired the choke to a KEY ON 12v spare circuit.

I am saving up for the MTF parts and also the Jon kasse heads. I just want to drive the car for a while bone stockish until the Boss 429 project begins.

Ok, but if it starts to tun bad, disconnect the choke wire then open the choke all the way and see if that fixes it.

Oh, that should be nice.