Choke, cold running misfire question

There is a metal pipe coming off of the cat housing that is flattened and rolled up.  I'm guessing that was the EGR pipe?  I'm assuming the cat housing is gutted as well.  It has been welded on one end.  I have NO inspections of any sort in NC.  Not even safety.  

But the truck runs dang good even with the carb leaking.  SO I'm thinking that's something that can be left in place.   It has a block off plate on the rear of that housing.  The extra 3/4 rise it provides can't really hurt that I see.  And it provides a little extra room under the choke area to "tickle" the fast idle screw.  

Coil clearance also.   I think I'll just leave it.  

Thanks for the help.

That is not the correct carburetor for your truck.  That specific carburetor was calibrated for a 5.0 with an AOD (Automatic Overdrive) transmission.  You can tell from the extra linkage on the throttle lever.  So, someone either switched the carburetor out with the wrong one or swapped transmissions.  

That carburetor was also calibrated for an EGR valve, and yours is missing.  The plate is still there under the carburetor, but the valve itself is MIA.  

And your hot air choke isn't even hooked up.  Your choke will never work correctly without it.

Everything works.  That said, it's hard to find a manual trans carb so far.  Rock Auto only has carbs for autos and AODs.  I have no idea the original trans in truck other than it was an auto.  This is a reman UREMCO carb.  from 2015 I think.   What are the differences?  

My trans was changed to a M5-od-R2 by someone else.   EGR has a plate, yes.   If I had same reman carb, it should run at least like it does now without the gas leaking at throttle linkage.  

In the past, I used YOUR idea for the choke tubes out of the Dorman housing and documented that elsewhere.  I still have the photo saved with these.   So it currently does have the choke hooked up and working at least as well as I can tinker it to work.   These are old photos, trying to figure out what the EGR plate was for.  

And gosh only knows what the engine was spec'd as.   Some sort of 302 (?) from AutoZone.  It will bark 2nd and runs pretty dang good for what it is, a 40 year old semi restored truck.  

I like my truck, just trying to make it a little better.

the truck was originally an auto as it still has the auto shifter column. how specific to get with everything being factory correct is absolutely "drivers' choice". Very minor differences between auto vs manual when it comes to carburetion other than fitting to linkages etc. if anything the auto tuning may have a slower vacuum response for a more sustained lower vacuum under load.  the air injection pipe at the cat converter would have originally gone to the thermactor system to supply air to the exhaust. many defeated ones are rolled and welded. many replacements come with a pipe that often gets done that way too.  the engine "is" getting more air and fuel as a result of the egr being removed and plated over and the cyl will run a little hotter and pinging can happen more so you may want to pull a degree or two back from your dist. advance. pinging and valve rattle can do damage. that's not to say that millions haven't run well and long without egr.
egr was designed to lower combustion temperature and the damage it can cause. egr systems do not operate all of the time and there are means which were built in to operate it when needed and not when unneeded

Thanks Mat.  Good information.  I haven't noticed any pinging.  Guys that did the engine swap are pretty good so they may have worked on all that.  

Those are refinements I'll be addressing next.  

I did order a new carb today.  Hopefully that will work out smoothly

engine swap? what was it before?

VIN indicates 302 originally.  But I have a receipt from PO that shows engine change and talking to garage that did the change said it was an Auto Zone reman 302 engine.

Beyond that, I don't know what's in the reman engine - nothing special I'm sure.  Probably embarrassingly low hp.   But the truck runs fine and does what a truck is supposed to.   Some vac lines gone and some plugged.   Emissions at least partially removed.   NC has NO inspections for this old a vehicle.  

most likely an autozone "long block". it's, time for an Edelbrock performer and avs 2 600 cfm carb. hey if you are going to delete half of the emissions, do it right ! haha

Send that to me and I'll install it!  No money for that and I like stock right now.   That might be for V 3.0.   We just up to V2.0 of me owning it.  But that is a great idea.  Along with some 5 slot mags, of Keystones or Cragars.  May as well dream big eh?

I have deleted nothing myself.  I'm driving it as I bought it other than fixing the choke.   Just now getting into making it better.

you gotta start somewhere.  how far are you from Salisbury by the way? i go there regularly and probably headed there in the next two weeks. I'm building an 83 f100 there. i just picked it up last month and im building the 5.0 for it to take out there and install along with a c6 for starters

I'm less than an hour from Salisbury.  Or right at an hour maybe.   Where are you in TN and what route do you take to get to Salisbury?  You may pass right by.

suburb of Nashville. I'm travelling I40 all the way to Statesville, then across to Salisbury just east of I85

Ok.  I'm on the I-81 to I-77 to I-74 route from TN to NC.   That passes within 3 miles of the house off of I-74.  But let me know when you're heading this way if you might need help or whatever.   Btw now and Christmas, probably won't have time, but who knows.

very kind. thats the true point of this forum .

New carb installed.   Worked well initially with a few idle adjustments.   Truck runs great.  Ran it up to 80 with more left.   It would run that before as well though.   But this one shows no leakage unlike the old one.   Still adjusting on the choke, though.  

How hot does the truck have to get to open the choke plate to vertical?  I only idled a bit and drove my short lap around the block - 2 or 3 miles yesterday (Sunday) and it wasn't completely open when I got home.  The temp gauge was up and moving at least near where it normally runs.  I didn't have a lot of time Sunday to fiddle with it.

I had set it Saturday to be completely open when truck was thouroughly warmed up, but I drove several more miles and scenarios on Saturday.  The whole choke system seems like a lot of adjustments to get all the factors working correctly.   Choke plate completely closed, vac pull down, fast idle speed, time on fast idle cam, time to open the plates completely.  

Pics are on my project page in that section.

There's really no way to accurately say when the choke should be completely off.  That's because there are so many variables, like outside air temp, how lean your carb is jetted, whether or not you have hot air plumbed to the carb and if that system is working, etc.

So the best thing to say is that it should be fully open when the engine no longer needs the extra fuel.  I'd expect that to be when the coolant temp is up fully and you've put some miles on the vehicle.

But the real test is how well the engine runs.  If everything is set up correctly it should start easily, keep running through warmup, and not have any bogs.  Plus, it shouldn't blow black smoke at any time, which indicates too much fuel.

It sounds like you have it set just about right.  But the fact that the choke wasn't fully off after your jaunt around the neighborhood suggests it might be a tad too rich.  Still, the proof is in the driving.

rcarlisle wrote

How hot does the truck have to get to open the choke plate to vertical?  I only idled a bit and drove my short lap around the block - 2 or 3 miles yesterday (Sunday) and it wasn't completely open when I got home.  The temp gauge was up and moving at least near where it normally runs.  I didn't have a lot of time Sunday to fiddle with it.

The choke plate *should* be completely open when your engine is at full operating temperature.  If it isn't, your [thermostatic] choke isn't getting enough hot air up to it.

rcarlisle wrote

The whole choke system seems like a lot of adjustments to get all the factors working correctly.   Choke plate completely closed, vac pull down, fast idle speed, time on fast idle cam, time to open the plates completely.  

Yes, and that is a big reason why all vehicles went to computer-controlled fuel injection.  But like Gary said, when the choke is set up and adjusted correctly, your truck should run as well as a fuel injected one, even in the coldest temperatures. Mine does.