Dies under acceleration

[stevechaos13]

Hey all.
I hit another snag in my truck. I finally got some of my parts in and decided to go try to throw em on this weekend. Went out and cranked the truck up and she sounded just fine. Started right off the bat, no struggle or anything and idled just fine. I had purchased one of those offset thermostat housings to allow clearance for my HEI dizzy, and decided to throw that on first. I marked the distributor position, pulled it loose and replaced the thermostat housing. Then I threw the distributor back on and cranked it up. Fired up just fine and idled normally. So I decided to take her around the block. Bad idea. I hopped in and tried to take off. It’s a residential area so I just crept out onto the road. No sweat. Once on the road it was a different story. She was running weak. I figured she was just cold and needed to warm up a bit and circulate. Took it down to the end of the street and tried to cross the highway. Punched it a little bit and she started sputtering bad, probably never got above 20 mph with the throttle to the floor and then died. Started up again just fine, but giving her any throttle whatsoever would kill her. I let her sit again for a second on the side of the road with the engine off, and then cranked her again. She fired right up, but still was lagging big time. I had limp her home by just barely tapping the pedal. Anything more and she threatened to die again. Got it back home though and lifted the hood. My first thought was fuel delivery, so I checked all my fuel lines for kinks or binds, and found nothing. I’m running two fuel filters, one below the fuel pump and one right after. They are both pretty new and looked fine. I did notice though that the one to the carb was almost full. I cranked the engine and opened tugged the throttle cable and it stumbled and died again. It sucked the fuel in, but it still died.
I’ve never had this problem before and I’m not sure what it could be. I’m going to change my spark plugs (mainly because I know they need it) and see if that helps, but I’m pretty much stumped. Other than that and maybe a fuel pump issue I don’t know what could be wrong. I’m running the stock mechanical fuel pump and it seems to be working just fine, but something past it is amiss.
How big of a deal is a PCV system? When I bought my truck, the PCV system had been disabled with the exception of the one coming out of the passenger side vavle cover. That one is hooked up the carb’s riser, but there isn’t one going into the air filter, and the one on the top of the oil fill hole has been capped off. I know it needs it, but it’s never acted adverse without having it hooked up. Could it be a factor?
Truck is a 65 f100 with a 460…

[64 f100]

If it wasn't doing this before you did your work, then I would start checking what I did, Otherwise, I would supect a fuel delivery problem. If not that, then it has to be electrical. I still think it may be fuel related even with your saying it dies . Easiest way to chekc electrical is timing light under these circumstances. If it just dies sounds like it has quit firing . I can't see where opening the throttle is the culprit there, though, unless it has very weak fire, and even that does not make sence. What I would do, is take the top of the carb off, and see haow much sediment has gotten thru the filters. I would replace the filter that is parially full, as this will call a leqan condition fuel wise. I would guess your not getting enough fuel to the car. You may have already gotten to much fine sediment into your carb also. The gas tank sounds like it needs a good cleaning, especially if it has sat for any length of time with the modern fuels in it without fuel additive for storing.

Rich

[stevechaos13]

Well, all I actually did was pull the dizzy and replace the thermostat housing. Nothing else got done past that because of this annoying little problem. Problem is though, that I didn’t try to drive it before I pulled the dizzy. I fired it up, and let it idle for awhile, which I do about once a week since it’s been sitting, just to let it circulate and cycle and whatnot.
What strikes me as odd is that after I messed with the distributor a bit I thought I had it solved. I got it to where it would idle higher, and I even pulled the throttle open a couple of times and revved it up pretty high and it didn’t die or stall. Then I hopped in a tried to take it out again. As soon as I would try to get on the gas it would start sputtering again and trying to die. So that’s what confuses me. Now it’s not dying as easy, but it still seems that under load it wants to…

[Kid]

float in the carb could be stuck, letting in enough gas to run but starves out with higher idle and under load

[jkimbrel65]

If you still have points check the gap.

[stevechaos13]

float in the carb could be stuck, letting in enough gas to run but starves out with higher idle and under load

That's a damn good possibility. I've been meaning to rebuild that carb for some time now, and figured it could be a culprit in this. That's also why I brought up the PCV issues. Does anyone have a diagram of the correct routing?

[Brian Taylor]

Steve,
You may have a resistor wire on the power for the new dizzy which might be making problems .
Also the way you describe the lack of accell. you might just have a dirty fuel filter.
Check the easy before you dig too deep.

[fendermender]

Set the timing with a timing light and check for vaccum
leak on advance.

Johnny

[stevechaos13]

Steve,
You may have a resistor wire on the power for the new dizzy which might be making problems .
Also the way you describe the lack of accell. you might just have a dirty fuel filter.
Check the easy before you dig too deep.

Are you talking about inside the dizzy or going to it? It might have one inside, but I know it doesn't have one going to it because I rewired the truck myself completely.
As for the filters, that shouldn't be the case, as I just changed them before I parked it.
I bought a new set of plugs to put in today and I'm going to throw them in, and re-time my dizzy this weekend and see if that helps. Beyond that, I might replace a couple of fuel lines too.

[63Longbow]

check those points , and see if they are advancing.....

[Tech]

If you have points and no resistor it doesn't take very long to burn up the points.

Check the timing
Check the points gap. It can get misadjusted just by adjusting the timing.
Your problem could be a very weak spark.
Tech

[Brian Taylor]

Steve,
If you are still having trouble with it I can come up and see what kind of trouble I can make.

[charliemccraney]

If you have points and no resistor it doesn't take very long to burn up the points.

Check the timing
Check the points gap. It can get misadjusted just by adjusting the timing.
Your problem could be a very weak spark.
Tech

This will be my guess, too. Burned points will allow it to idle, and rev with no load but when there is a load on it, performance will be less than satisfactory. If this is the case, the easiest solution will be to get a coil with an internal resistor, for use with points.

This is what happens when points are run without the proper resistance. This set lasted about 5000 miles. With these, the symptoms were it idles fine, it revs fine, but on the road, it would start missing around 4000rpm. Lesson learned, points changed, 3 ohm coil installed and problem solved.

[stevechaos13]

Hmmm...
Good thinking guys and that would have been my first guess too, excpet that I don't have points anymore. I'm running HEI. If it's a weak spark it's coming from the module malfunctioning. But I don't think that's the case. My dizzy has a clear cap, and you can see it spark. The sparks are bright blue, and look very strong.
I'm gonna throw a new set of plugs in tomorrow and see how that helps her. I think I may have had a similar problem before due to plugs on one of my other cars, but of course since my truck ins't sitting at my house, everytime I have an epiphany I can't run out and test it! I know that my number one plug was loose, and tightening it seemed to help a little, but I didn't get enough chance to check the rest. I ran out of daylight and it was f*&cking cold!
I've got a whole grocery list of things to do to her this weekend. She's getting her kickdown (finally), a throttle cable (no more coat hanger wire!), new plugs, a new passenger side door, a 3" drop in the back, and a new fuel gauge sender! I can't wait to get this stuff all installed and have her back on the road. BUT she won't be going anywhere if I can't get this lack of acceleration problem fixed.
Come to think of it, the last time I took her out and around the block she was hesitant too. This truck used ot be a screamer. You could punch it and break the tires free stopped or moving. Sad to see her just kind hunch down the road...
Brian, you're welcome to come out at see how much more damage both of us can do... LOL!

[William-in-St George]

Carefully examind the plugs at the dizzy and cap. Then consider adding a 30 amp relay into the run circuit. Use the key on hot wire to actuate the relay and some nice heavy 12 gage wire from the battery to the relay and from the relay to the dizzy. If you are using the Accel plug you can see that they provide a 12 gage wire pigtale for the hot in connection. Having a steady 12v + power supply is crucial with these HEI dizzys. And a relay takes all the stress off your ignition switch which already has plenty to do. You can use the same relay to turn on the tac or anything else that needs ignition on power since the relay has two hot outs. After that consider replacing the control unit in the dizzy with a good quality aftermarket unit, and lastly replace the coil. These Pro Comp dizzys work pretty well but I have had control module and coil issues. Do you have a source and PN# for the flat thermostat housing? I need another one and as usual I have forgotten where I put the PN#.

[Lowell]

Make sure the wire from the coil to the points is good. Ive seen them with the wires broken inside the insulation and the engine would cut out when the advance plate moved by the vacuum.

[stevechaos13]

All the mention of vaccum brings up a question in my mind. How exactly can I assure that my vacuum system is working correctly? I’ve got the hose hooked up to the vacuum advance on my distributor, but only out of habit. I can’t even tell you that I know exactly where it goes. The PO was a moron, and I’m still undoing all the southern engineering that he had done. Seems like everytime something on the truck goes down, or something seems off and I’m under there working on it, I find more stuff that has been jury rigged. There are numerous ports on my carb that aren’t hooked up, and even though it looks like ass, it seems to work (usually) but, I’m sure they could be causing little problems that could add up to big ones. Any body got a diagram of the vacuum advance system and how it’s supposed to be?

[Lowell]

If the vacuum advance is good you shouldnt be able to blow or suck air through a hose connected to the diapfram on the dist. if you happen to be a smoker you shouldnt be able to blow smoke out of the distributor. if it is bad the engine will stumble on acceleration but it wont cut out completley. You could unhook the hose and plug it and go for a test drive .

[Obsa]

Steve I didn't see where you said what carburetor you have but there are two different places to pull vacuum for the distributor. I agree with Rich I believe you might have a fuel supply problem.

Here is a link to FordMuscle's tech pages there might be somethings there to help you out.

http://www.fordmuscle.com/TechDepartment/ignition.php

[William-in-St George]

It could be a fuel starvation problem, the pump, the filters, kinked line, floats or crap in the carburetor. I still think its electrical. Put a timing light on it and rev the engine gently, the timing mark should advance (centrifugal advance at work). Take off a plug wire and wearing gloves or a rag, hold the end of the wire near the engine block. You should see and hear a snapping blue spark that seems to be capable of knocking the paint off the engine. If not, its coil or module. IMHO!