Too lean....

EGR effectively richens the mixture by displacing some of the oxygen in the intake charge.
This slows the burn because there are less highly reactive oxygen molecules available to spread the flame front.
This allows you to get away with more advance, because the burning charge is not creating more pressure against the rising piston.

 

Oh bummer! I wondered if I had that backwards. Thanks for catching that, Jim.

 

Somewhere on the early interwebz there was a multipage manifesto by a retired GM engineer explaining EGR and why he felt it was necessary not only to reduce NOX, but to get the performance we expect from 'modern fuels and engines'.

I'm not even going to start searching for a link, everybody has seen it before.

 

Not written by Gary?

 

E2PZ-9A586-U replaced E2PZ-9A586-B (Motorcraft CT-1441 replaced CT-1327).

 

Hard to believe, huh?

 

Well I messed with the truck some, used my vacuum hand pump on the choke pull off, didn't seem to want to pull the choke open so swapped my motorcraft one I bought for my mercury on and without any adjustments it was actually pulling the choke open. The other would pull but wouldn't pull the choke open.

So now I got it where the truck will start on its own again like it used to. Hot restarts, after engine was hot shut it off let it sit about 5 to 10 minutes hit key fired right up ran for a few seconds dropped dead. The up side is when I hit the key again truck fired up again and continued to run. Before you had to crank on it and hold the throttle down some like you were clearing out a flood. Not doing that now with this new choke pull off. Fuel filter I pulled old off I could blow through it as easily as the new one so I put the old one back on since the new one looks like someone started cross threading it and I couldn't get it to start.

aside from that got the truck running decent, has a roughness in it at idle in gear even with the A/C off so need to play around with it some more but think I will wait till I get the carb kit to go through it and go from there.

When it dropped dead on me on the initial restart hot I had the aircleaner off already and I quickly looked down the carb just after it died to see if it was dripping or pouring fuel in. Nothing was dripping from the boosters so I honestly do not believe the truck died from flooding out. Might be right might be an electrical problem. Thing is though I did a wiggle test on all ignition connectors and no change. So now I am wondering what could it be. I need to check and see I don't think I changed the coil I have to see if I can find receipts or if I can look at it closer and see if it looks fairly new. I also don't believe it could be the new Motorcraft ignition module I put in cause thoses they go dead they are dead I never really heard of one acting like this. Distributor is new lifetime warranty CARQUEST brand, plugs are new motorcraft plugs, and plug wires are new Ford racing 9mm wires. All this was done earlier this year when I had a miss and cut out while cruising on the highway for a second. Hasn't done that again.

 

It sounds like the choke was coming back on and now the vacuum pull-off is fixing that.

 

That's what I think too cause when I would restart it after the truck sat for 30 minutes or so during lunch when I would get back in to go back to work it would start up run for a moment then drop dead. Then when you hit the key you just had to crank on it. Unless you slightly depressed the throttle down it would start up but youd have to hold it around 1500 rpm for a bit to clear out the flood.

So I fixed that. But I am just wondering what this dropping dead is being caused by now. Cause it still does it but it starts right back up without having to hit the throttle.

I'm wondering if it could be something like a leaky power valve or leaky needle and seat. After all this carb is very old and hasn't been apart. Will still go through with the rebuild anyways I just hope I don't have some electrical problem that is causing the drop dead but I find it odd it only does it on hot restarts if the engine fully cools off it doesn't do it.

 

That kind of heat-related failure is a common symptom of ignition module failure, sometimes the ignition switch itself... might investigate that stuff sometime....

 

the module has been replaced earlier this year with a NOS Motorcraft one. The ignition switch how ever has never been replaced as far as I know.

maybe take and unplug my new motorcraft ignition module and plug in a old one that I know was good when it was removed and see if that corrects the hot restart.

 

That's a good way to diagnose, see if the problem goes with the change or not; if not, change it back and proceed on.

 

Yep, the truck I converted to a 5.0 Coyote engine I took the ignition module from it and kept it I knew it was good as it was a running and driving truck when he brought it in for this conversion so I might take and swap it out tomorrow. Take and warm truck up let it sit restart it verify its still doing it then swap the module run it then let it sit and try it again.

 

Well drove the truck today, same thing. Got to the store hit the throttle and quickly let off as people walked out infront of me truck stalled out then had to crank on it and crank on it to get it to start. Then came out started truck up after about 15 minutes of being in the store fired up dropped dead cranked on it about 4 seconds it started up ran on its own but surged till I held the throttle up slightly and cleared the fuel out.

So its still flooding out on shutting off when hot. I am not sure what it is I will rebuild the carb cause I saw no fuel leaking but I did hear that a bad power valve on these carbs will cause it to run rich. I asked my rider today if they smelled fuel they said it didn't smell rich today. So now I am at a loss. Maybe take and pull the air pump belt off since I have no converters the thing is causing my exhaust temps to push 650* easily maybe its boiling the fuel on the heat cross over.

 

That's what I was just gonna suggest; have you gone down that path and looked at, say, the phenolic spacers and such that people use to insulate the carburetor?