Resurgence of a F100

6speedsd

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Drove into town and had to manually downshift at every stop. It started in 3rd every time. Went on to the part store and grabbed a be modulator. On my way home, it only did it at the first stop. Rest of the time shifts were right, it downshifted to first at a stop, upshifted to 3rd at a decent rpm. Some of the reading I’ve done says the governor is sticking some. Thinking back, I can’t say for sure if I actually took it apart and cleaned it up or not when I did the rebuild. Wasn’t doing this before the rebuild so I’m not sure why it’d start now, unless a piece of something got freed up and made its way into there. Anything is possible I suppose.


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mandkole

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The vacuum seems a little low. Running about 12-13deg initial advance? May need to plug all ports at carb to confirm no vac leaks.

Can’t comment on the trans trouble shooting. Run all manual and reverse pattern here.
 

psduser1

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Sounds like you are gaining on the vacuum issue.
I assume you've double checked the throttle blade position at idle? I.e. fully closed?
Try spraying some wd40/carb cleaner all around and over the carb (not directly into the carb) to verify no vacuum leaks? I cant remember if you've covered that, too lazy to reread the thread, lol.
Have you played with the distributor setting at all during this process? Sometimes you can gain a bit of vacuum reading by retarding timing a degree or two. Of course, you'll want to keep an eye on how the engine starts as you change timing, it's a bit of a balancing act. Quite often I found that the recommended number was close, but not perfect, depending on the combination of carb/cam/heads. Of course, double check your vacuum with carb changes after any timing changes, as it will change you carb adjustment.
It is a time consuming process, but it can pay off, and if you are only a 1/2 turn out on the idle screws, and still rich, I think you'll be a lot happier.
Sorry if you've already discussed this, just trying to cover all the bases. When you get it perfect, you know we expect a video, right? Preferably a burnout, or a drive by under load!:p
 

6speedsd

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Timing is 12 degrees initial. I checked that this morning too. Only used port on the carb when I checked vacuum was the vacuum advance port which I never disconnected or plugged. Just left the distributor hooked up. I’m using that port, and my full manifold vacuum port to supply the modulator and hvac. Checked it this morning via the full manifold port.

Throttle blade are the one thing I did not check. Idle mix screws were set at about a turn and 1/4 out of the box. I’m at about 1.5-1 3/4 turns out now.


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6speedsd

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I’ll Spray around the carb next chance I get. And may even drop timing down to 10 just to see how vacuum changes. I’m at 12 initial now, and running 87 octane I’ve yet to hear any pinging. I need a better tach for sure though. I layed into it earlier and the tach showed 3500, which was in no way correct! It was screaming. I have the Msd box rev limiter set at 5500, so I shouldn’t have to worry about that. It will do a burnout now though! It wouldn’t before, so something must be better this go round.

As for the trans, I need to pull the tail shaft and clean the governor. For now, it it acts dumb, I’ll just manually shift it.

And yes, if I can get someone to do it, I’ll get a video later. My wife won’t because she’d just bitch the whole time about how I’m “going to tear it up”.


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psduser1

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Timing is 12 degrees initial. I checked that this morning too. Only used port on the carb when I checked vacuum was the vacuum advance port which I never disconnected or plugged. Just left the distributor hooked up. I’m using that port, and my full manifold vacuum port to supply the modulator and hvac. Checked it this morning via the full manifold port.

Throttle blade are the one thing I did not check. Idle mix screws were set at about a turn and 1/4 out of the box. I’m at about 1.5-1 3/4 turns out now.


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Definitely check the throttle blades, I've seen them hang up, even on new carbs. Sometimes, just a bit of bind when you tighten the carb down to the manifold.
As long as your port is below the throttle blades-not the choke blades- vacuum should be the same anywhere you check it.
One-two turns is generally a good starting point, but if you are rich, and everything else is "right", I wouldn't be afraid to go less, at least till you start giving up throttle response.
 

6speedsd

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Couple quick checks this morning before work.....sprayed carb cleaner all around the base of the carb, vacuum ports, shafts, etc and no change in idle, so I think I can rule out leaks there. Best I can tell, blades are closed at idle. Sort of hard to get up there and see. I can’t see a definite opening regardless, so if they are open, it’s a tiny amount. I tried looking myself, used a mirror, even took pics with my phone. I can’t see a gap, but like I said, it’s hard to make out much.


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mandkole

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Sounds good — As long as you are not making big curb idle adjustments with the throttle stop screw, all is well.

Hopefully you get a handle on the trans soon.
 

6speedsd

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Yet another rainy day so I'm home again. Got the governor off the trans and cleaned it up. Neither valve would move freely. A lot of carb cleaner, some time with a scotchbrite pad, and a half hour later it's all moving smooth and free again. Seemed to fix my issue. Truck now downshifts at a stop which it didn't do before. Sometimes I still have to manually drop it to 2nd if I'm turning onto another road or something...for whatever reason it'll still say in 3rd then, but that might work itself out with more driving. It now also shifts to 3rd at 45ish mph under light throttle, which I can live with. Before the cleaning it was 60+ before it'd shift up.

Have to swap my old alternator back on tomorrow. The TuffStuff 100amp I've had for a year is yet again about to eat it's bearings. I've already had one warranty replacement 6mths ago, now it's doing the same thing again. Talked with the company I bought it from and they of course claim they never have warranty claims on them, blah blah blah. At least they are sending me a refund check and I'll just be done with them and go back to the factory style Ford part. I went one wire just to clean up wiring under the hood...look where that got me! Oh well, chit happens right. Now I have to see if I can find that wiring harness again!

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6speedsd

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Anyone know what year GM one wire alternators have the same mounting tabs as the Ford style does? Before I call and get the run around from some idiot parts counter keyboard tapper.


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rusty1161

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Anyone know what year GM one wire alternators have the same mounting tabs as the Ford style does? Before I call and get the run around from some idiot parts counter keyboard tapper.


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Check out the ones CVF Racing carries. I have their pulleys and alternator on my 289, and quality is great.

https://www.cvfracing.com/accessories/alternators/

Rusty
 

6speedsd

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Are the shaft sizes the same as the old style? I'd need to lose the serp belt pulley and install one for a V belt.

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mandkole

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Sure, its the same shaft. Just required some minor shimming to deal with the offset differences. This pic was the first install before the electric water pump and CRF brackets.
 

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lincolnlocker

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Sure, its the same shaft. Just required some minor shimming to deal with the offset differences. This pic was the first install before the electric water pump and CRF brackets.
That looks nice and clean. Im starting to miss the days of being able to see and work every part of the engine in the truck.

live life full throttle
 

6speedsd

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Good deal. I might give that a go then. I'll need a new unit regardless, since the stocker I had was making some noise when I took it off. It was old for sure.

What extra connections are needed with that one aside from the battery wire?

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6speedsd

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That looks nice and clean. Im starting to miss the days of being able to see and work every part of the engine in the truck.

live life full throttle
It's kinda nice! I work on this one a while, then work on something newer, and cuss the newer thing the whole time I'm doing it. A clean engine bay is a thing of the past.

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mandkole

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Good deal. I might give that a go then. I'll need a new unit regardless, since the stocker I had was making some noise when I took it off. It was old for sure.

What extra connections are needed with that one aside from the battery wire?

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In the amazon link , there’s two plugged harnesse/wires that you need. The regulator harness and the field exciter wire.
 

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