223 low idle and choke problems; What does your 223 idle at?

[Renegade]

Hello all, I own a 1956 Ford F-100 that has a 223 that has zero miles on a rebuild, I just can't get it running right.
I have gone to EVERYONE for any help and nothing has worked. I am this "ll" close to giving up on this expensive new rebuilt motor simply because I just can't get anywhere. This is my last hope and final straw because I honestly don't have a single clue what else to do.

I have two main problems:
1)The idle in the Ford shop manual says it should be at 450rpm. The engine will not under any circumstance run smoothly below 800.

2) Under no circumstance will the engine run with the choke plate fully open.


I had the carb rebuilt by a man named Michael Mayben, maybe some of you Holley guys know him, so I know the carb is absolutely perfect.

Because of these problems I can't properly tune the carb with a vacuum gauge, so the thing just doesn't run perfectly.
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Things I've tried:
-Vac gauge--The needle is a little fidgety, but it doesn't move very much at all, I can post a video if you care. It doesn't indicate a serious vacuum leak.
-Spray starter fluid around manifold to see if rpm increases from a vac leak, nothing.
-Full and proper carb rebuild.
-Clean and check ignition multiple times
-Fuel delivery is optimal
-Many little things that don't come to mind.


I don't see the point in driving the truck if I can't tune it to run right, and I can't tune it with the current issues. I was told if it runs out of tune enough that I can burn a valve/piston, cylinder wash(of oil), Bad mileage, premature engine failure, just the basics. But if I can't get this thing running better, should I just throw the damn engine in the trash?? :|

Thank you so very much.

P.S.--So what rpm does your 223 idle at? Will yours go to anything below 700? 450? Will yours idle with choke open completely?

 

[JimKoz]

Mine will idle at 450 and below with the choke completely open. I run an Autolite 1100, which may be inferior to the Holley 1904 that you probably have. Getting the vacuum leaks sealed and the ignition system in good working order was key, though. I even installed a smaller PCV valve from a Pontiac "Iron Duke" application to get even more vacuum.

I think Mike Mayben is the International Harvester guy, right? I'm pretty sure he tests his carbs on a running engine before he sends them out. That doesn't mean that something can't go wrong between testing and installing. I'd be tempted to borrow a carburetor from a running 223 if I could. They're very sensitive to fuel pressure, but you probably already knew that.

Your engine is recently rebuilt, right? If so, one common mistake with a 223 or a Y-block is to improperly index the camshaft sprocket relative to the crankshaft sprocket. The marks aren't supposed to line up like they do on every OTHER engine I've ever seen. Ford's better idea back then was to offset the marks by 6 links of the timing chain so that the timing marks were both pointing at about the 2-o'clock position. Just one or two links off might allow the engine to start, but run poorly.

 

[59F100]

Tell us a little more about the engine.
Single barrel carb?
Does the new cam have stock cam figures (lift/duration)?
Was the installation/degree verified?
Have you checked valve lash?
Compression?
What vacuum readings are you getting?
What are your plugs gapped at?
Are all plugs firing?
What type of ignition (LOM or duraspark?)?
Gap/dwell settings?
where is the timing set at idle?
how are you checking rpm?
How does it not "run right"? Does it just not idle down below 800rpm? how does it drive?
etc...

These are some of the questions I would be asking you in a BS session. My 223 (stock) will EASILY idle below 800 rpm and at 450rpm (you can almost count the rocker movement. Granted, it doesn't run worth a turd when you load it down, but it starts and idles like a new engine. Give us more info and lets go from there.

 

[Renegade]

Mine will idle at 450 and below with the choke completely open. I run an Autolite 1100, which may be inferior to the Holley 1904 that you probably have. Getting the vacuum leaks sealed and the ignition system in good working order was key, though. I even installed a smaller PCV valve from a Pontiac "Iron Duke" application to get even more vacuum.

Never thought of that. But I tried undoing the PVC and just blocking it and it didn't change anything.

Your engine is recently rebuilt, right? If so, one common mistake with a 223 or a Y-block is to improperly index the camshaft sprocket relative to the crankshaft sprocket. The marks aren't supposed to line up like they do on every OTHER engine I've ever seen. Ford's better idea back then was to offset the marks by 6 links of the timing chain so that the timing marks were both pointing at about the 2-o'clock position. Just one or two links off might allow the engine to start, but run poorly.

No kiddin? Damn, I didn't check the static timing before installation. When you pay a shop that's been in the business for 40 years thousands of dollars, you'd think they'd time it right. Only reason I didn't check.
The thing is, it runs pretty well at other times. If you revv it up it'll be smooth. Just seems to idle rough. especially below 800.
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Tell us a little more about the engine.
Single barrel carb? Yes, Mayben told me it was actually a Holley 1960 and that is correct for my truck

Does the new cam have stock cam figures (lift/duration)? I asked for a stock cam, yes. Motor is bored 0.080" Max bore

Was the installation/degree verified?No, dangit, and that isn't the first time I've been asked that.I regret that now

Have you checked valve lash? To be honest, no. Afraid to deal with a valve cover leak...they had to have set it right.

Compression? Something that's been on my mind for a couple weeks now.

What vacuum readings are you getting?Depending on timing, 15-20 inches. If I advance the timing a tad more than stock, it'll be at 20". With Stock timing vac is 15"

What are your plugs gapped at?Not sure the exact amount but I KNOW it's the spec as per the book, and the plugs are correct

Are all plugs firing?Yes

What type of ignition (LOM or duraspark?)?No clue, hahaha. It's what looks to be original to the truck from '56. Any way I can help you identify?

Gap/dwell settings?gap is the spec of 0.024"....the dwell is hitting the nail on the head at 37º

where is the timing set at idle?The spec as per the shop manual: 4ºBTDC. I have advanced it a few times trying to tune the carb, but I set it back recently

how are you checking rpm?An old tach that my dad's had for a while. It's a tool, not just a gauge. Tests Dwell and one other thing too.

How does it not "run right"? Does it just not idle down below 800rpm? how does it drive?
etc...It will idle down to 5-600, but rough as hell and may even die. But you also forgot the choke issue. Will NOT run at all ever with the choke open fully(unless foot on gas.

I have never driven this truck....Just around the block to park it, no acceleration or anything.Just want to get that out there.

These are some of the questions I would be asking you in a BS session. My 223 (stock) will EASILY idle below 800 rpm and at 450rpm (you can almost count the rocker movement. Granted, it doesn't run worth a turd when you load it down, but it starts and idles like a new engine. Give us more info and lets go from there.

What do you mean "it doesn't run worth a turd when you load it down". Is that the way all 223's are? Or are you just speaking of when the idle is at 450?

Are your idles set at 450? Or do you just know it will idle there, but it's set higher?



I have some work to do! You guys have been more help than anyone for the last month!! Thank you so much. Ask for anything else, I'll do what I can!

 

[59F100]

What do you mean "it doesn't run worth a turd when you load it down". Is that the way all 223's are? Or are you just speaking of when the idle is at 450?

My 223 would bog real bad when you put a load on it. In other words it would die/cough/sputter when you put your foot in the pedal. It would start hot or cold on the first try, even on winter days, idle real nice, rev, etc...just wouldnt run down the road. I have done some work to it since and hope to try again here in a few weeks. It should run better but I am probably still looking at a new cam, bearings, and rings.

Are your idles set at 450? Or do you just know it will idle there, but it's set higher?

It will idle at 450 according to my dwell/tach meter. I think the idle is set around 475.

I have some work to do! You guys have been more help than anyone for the last month!! Thank you so much. Ask for anything else, I'll do what I can!

That's why this site is here. Check on some of the unknowns mentioned and report back.

 

[Renegade]

Thank you very much, hopefully I'll start with the compression test in the next couple of days.

About the ignition, whats an LOM, and how is it different than a duraspark?





Hey, I just had an epiphany. You can tell if the crank/cam relationship isn't correct simply by getting the motor to TDC, technically. If the piston is at TDC, and the valves are completely closed, then they should be fine.

To confirm this I checked that when I first got the motor, so I know for a fact that the cam/crank are times together properly!

 

[manglass]

Since you mention the engine won't idle properly with the choke fully open. I would suggest the first thing you check is for a (large) vacuum leak. Secondly, a clogged idle jet. I know you're sure the carb was rebuilt properly but it could have injested contamination from the vehicle fuel system.

Lou Manglass

 

[Renegade]

Since you mention the engine won't idle properly with the choke fully open. I would suggest the first thing you check is for a (large) vacuum leak. Secondly, a clogged idle jet. I know you're sure the carb was rebuilt properly but it could have injested contamination from the vehicle fuel system.

Lou Manglass

The carb has two fuel filters, one before the pump and one after the pump, I don't think the main jet has a problem.

About the vac leak, that is interesting, I've been told that time and time again, and the needle on the vacuum gauge doesn't stay perfectly still. Almost, but not quite. I think that's one of my problems. But there seems to be no manifold leak........I just need to keep hunting it down, there must be a leak somewhere.


Thank you for your input.

 

[Drumhead_Dan]

Things I would check:

Run the truck at 800 rpm, or whatever you can do it get it somewhat smooth. Throw a timing light on each plug wire, check where your final timing is at and all cylinders are firing smoothly. Check fuel flow by gallons per hour and pressure. A non-vented cap or some other odd thing might be screwing you. Two fuel filters might be messing with you. Check to ensure carb heat bypass in the exhaust manifold is operating and not clogged under the carb. Because the carb seems to be running lean and a vac leak that large would be heard from the cab I would say it almost has to be in the fuel delivery system, but a tooth off on the dizzy might give a similar result. I don't think a mis-matched load-o-matic would cause this sort of issue, but I haven't had it come up. Good luck.

 

[Renegade]

The carb heat bypass is nonexistent. Someone removed the whole thing a long time ago. But that didn't affect the way this truck ran when it was last running 20 years ago.....

Explain to me checking the timing of each wire....?

The dizzy being a tooth off wouldn't matter as long as the timing was correctly set, right? It's set right at 4ºBTDC

 

[Drumhead_Dan]

4 degrees would be on the number one cylinder. If you put the sensor on each plug wire in turn and watch the flash it should beat steady. This is to ensure there is no cross-firing and each plug is firing steadily. Checking for a tooth off should be easy enough, roll the engine up to 4 btdc and physically look at the rotor in the dizzy. It should point right at or very close to the number one spark plug on the cap. What you're saying sounds right about if #1 is at 4 degrees, but for some reason I think I'm missing something about that. At 800 rpm you should be showing a lot more advance than 4 degrees is what I'm thinking.

Did you look over the load-o-matic info?

 

[Renegade]

You have to remove the vac advance for any and all tuning. It is removed if that explains the lack of advance.

Yes, the advance works as normal. I totally forgot to mention it's been unhook this whole time.
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This is sort of a pointless update, but I just went out and re-oiled and torqued all of the IM bolts and fired it up, at stock timing it eventually gets to about 19" of vac but the needle is still fidgety... On the gauge it doesn't fidget more than HALF of an inch of vac, very very little, but it is still fidgety nonetheless.

About the choke, it's very very touchy. It will purr like a kitten at one point of the choke(~1200rpm, no vac advance), and all you do is push it in any amount your hand can feel, not even measurable, and the truck will start spitting and sputtering, missing. Take it even further and it will plain out die.

I still need to check the compression. The fuel bowl level is perfect, so I think the pressure is just fine.

 

[Drumhead_Dan]

Just a chance... but the choke cable isn't grounding anything out under the dash, is it? How much vac are you showing at the distr?

 

[Renegade]

From what I can tell the dizzy doesn't pull vac??? :

 

[Drumhead_Dan]

Vac from the carb at the distr.

 

[Renegade]

Oh, so at the end of the vac tube? Ok I'll get that ASAP.

It should be nil though, since it's above the throttle plate. There really is not vac above the throttle plate at idle.

 

[Drumhead_Dan]

With the breather on it shouldn't be much, but there should be some at that rpm.

 

[59F100]

Renegade, whats the latest on your truck :

 

[Renegade]

--I just got a compression tester from a friend. I'll be doing that either later today, or tomorrow. I have some school related things to finish. :x
--I took the IM off and had a shop belt-sand(resurface) it so all of the ports line up perfectly. I didn't do that before. New gasket. I also Magnafluxed it to recheck for cracks.

I LITERALLY just came into my house from installing everything back. It's ready to be comp tested. 8)


Unfortunately, this truck has wronged me so many times, I am now pessimistic....

.......I highly doubt I fixed anything. :thumbdown:



Either way, Thanks for asking. I didn't update because there was nothing done so far. I had to wait until the holidays were over for parts and the shop.

 

[Renegade]

Just as I suspected.
Not a damn thing changed.

Comp test revealed:
Cyl1-130
Cyl2-140
Cyl3-140
Cyl4-140
Cyl5-150
Cyl6-140

Vacuum gauge still fidgets. Engine still won't idle smooth under 800rpm. Engine still won't operate with choke open.

I'll post a video later.




Well, this is(was) my last stand. I am done with this truck and motor. Nothing has worked; nothing has changed anything. It's been rebuilt for a year and a half; it's been running for the last 9 months(and yet the chassis hasn't moved more than a half mile). Nothing has gotten better. All the same. I think I'm done(I think it is too). :thumbdown:

You guys had the best ideas and really helped a lot. You also seem like the definite I-6 experts. If I feel like trying again someday, I'll be back here.