One other thing when I pull the gas cap off after just sitting idling for a bit. There is a ton of suction.

 

If you have black sutt coming out of the exhaust it is running to rich. Make sure the choke is set correctly and the air fuel mixture needle is adjusted properly.

 

Now that I have the brake line fixed I can concentrate on how the truck is running.
I feel that the new Carb, fuel pump, dizzy cap Have cleaned up how the truck runs for sure.
I dont see the black soot anymore so I feel the carb is pretty well tuned in.

However the truck still feels allot less powerful then when the old carb was on there. Now I can be crusing down the road and give her some gas and she instantly hiccups then moves on, as though there was either a lack of fuel, to much fuel, or a fire issue. Specifically when I change gears and then hit the gas it hiccups, and then moves on.

I have lost the sputter under light thorttle while going down the road though.

 

Hey fusion, I didn't know there was a ton of suction when you took the gas cap off......you have a non-vented cap used with evap systems where the air coming into your tank to replace the gas you use comes through the system for vapor recovery. Older systems did NOT use this and vented the tank through the cap. They used to say vented or non-vented on the cap, but I haven't noticed this lately.

As an experiment, try running with your cap on, but not fully tight, preferably not with a full tank of gas. If the power problem goes away, you need to get a VENTED cap. Just another thought.

Dave

P. S. What year is the truck, anyway?

 

The truck is a 68. I'll try loosening the cap to see what that does.

 

Runs the same with the cap loose or tight. I though about swithing the coil back to the Accell just to see if that makes a difference, right now I have an Autozone 19 dollar coil in there.

Also I have the dual advance dizzy, but one of the vacumm ports is plugged and the one on the side is only being used. If I hooked up a vacumm pump, say one for brake bleeding to this port should I be able to pull enough vacumm to see the control arm move inside?

 

Ok more info for you guys and a question.

I've been trying out different scenerios to try and pinpoint my issue.

Issue #1 At idle after full warmed if I attempt to rev the motor with approx 1/2 throttle or more the engine chokes for a second then picks up speed.
Issue #2 If I pull out into traffic and give the truck more then 1/2 throttle in any gear, it nose dives almost cuts off then regains itself...but still feels really week when it regains itself.
Issue #3 I hooked a vacumm pump up to the outside Vacumm port on the dizzy the one closest to the firewall, applied about 15HG of Vac and the control arm inside didnt move. I tried the same thing on the Vacumm port directly on top of the dizzy and the control arm moved some. So I moved the vacumm line from the carb to that one, and capped off the other port.
Issue# 4 I performed just a standard air/fule screw adjustment of 1.5 turns out. Took the truck for a test drive, and while I was able to rev at idle. I was unable to get on it in any gear., it stumbled as though it wanted to cut out. I moved this to 2, 2.5 and 3 turns out all with the same results. Sometimes worse then others
Issue# 5 First gear is good for about 10 MPH, but I used to be able to put it in second at that point and go..but now it stumbles and bucks until about 20-25 MPH. Additionally third gear used to work well from 30mph up. However it also stumbles when shifting at that speed.

The only other thing I could think is maybe I have a bad plug or to, they are motorcraft plugs and pretty new. But who knows. When I took them out while putting the new carb on. All where black with a slight bit of greyness on the top. Non where wet.

Also on the right side of the carb there is a screw that faces down, it attached to an arm and spring, and moves during throttle. Do I need to adjust this screw?

Finally a question. Maybe I have been doing this wrong all along. If I turn the air/fuel screw clockwise all the way in the truck cuts off as I heard it should, but by doing this am I leaning it out all the way, or allowing to much fuel?

 

So this morning its about 55 degrees, so I pull the choke and after to tries she cranks right up. I let her idle there with half choke for about 10 minutes until I see 170ish on the temp gauge. I push the choke in, pull out of my driveway and immedialty the truck is sputtering. What the heck!.
I rev it a bit and all seems fine. Go to pull out of my subdivision give her about 1/3 throttle and she dies right there in the middle of the road. Cars coming I'm freaking out, and she wont start, so I throw her in first and just hit the starter to move me out of the way thank god for a strong starter!.
Get her cranked turn around and inch up the hill back home.

I've about given up.

 

Quote "Issue #3 I hooked a vacumm pump up to the outside Vacumm port on the dizzy the one closest to the firewall, applied about 15HG of Vac and the control arm inside didnt move. I tried the same thing on the Vacumm port directly on top of the dizzy and the control arm moved some. So I moved the vacumm line from the carb to that one, and capped off the other port. "

The port farthest from the distrib is the advance and should move away from the distrib with vacuum. The other on is the "Vacuum retard" It should push the rod toward the distrib with vacuum. You an replace the Vac advance with a single advance unit.

It sounds like you may have an Ignition advance related issue.

Chris

 

So even though the truck came with a dual advanced dizzy its ok to order just a single at the store? I'm going to try this since its only 38 dollars for a new one. Thanks

 

Yeah you can. I did that with my 68 Cougar with a 302, It had california emissions, I unhooked the retard line to simplify and improve performance. Then when the advance mechanism finally failed a few years later, I installed a single advance unit.

Chris

 

Right now I have the dizzy set up for approx 12 degrees on the timing, so on heavy acceleration or any acceleration for that matter this should increase to approx what?

 

Could some semi bent push rods cause this issue. I havent taken the cover off but was just wondering....

Should have the new Dizzy sometime tomorrow or Tuesday.,

 

Ok so I got the new dizzy in there and the truck cranks right up. At idle if I put it to the floor it bogs down, sputters a bit then revs.
So I replaced the autozone coil with my old accell coil, and the issue seemed to improve a great deal.
I took it for a test drive and its for sure a ton smoother, however it still bogs during shifts. If I am on the gas approx 1/2 throttle, shift to second, it bogs down for about 1-2 seconds then picks back up.
I'm running 14 degrees timing right now, two turns out on the carb, and .35 on the plug gap with the accell coil. Would increasing the plug gap help at all?

 

14 degrees sound like a little bit to much. Try setting it somewhere between 6 and 10 degrees before TDC and see if that helps any.

If you have a vacuum gauge try and set your air fuel mixture screw on the carb by it. Just adjust it in and out to get the highest reading you can. If you pull off a vacuum line from the intake manifold and the engine speeds up then it is getting to much gas, if it starts to miss out the it air fuel mixture should be pretty close. Are you sure you don't have any vacuum leaks anywhere from gaskets or lines?