All Plugs Fouling on Right Bank

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Will be checking tomorrow. Worked my a$$ off this week, no time to play with it.
 
Finally playing with it today. Rod was not bent. I put it back in and fouling is gone. That's the good news.
But I have a nasty stumble off idle. I've set the initial at 15* before, she's warmed up and idling at 800 (manual transmission). The choke is fully open. The smoothest and the highest I can get her to idle is with the two idle mixture adjusting screws turned full counterclockwise (richest setting, says the manual). I feel it should be idling a little smoother.
 
float level set to low or you need to jet up. Remember, with out that metering rod in the jet hole, that's way bigger jet..........
Take the top off and check the float, jet it up and see what happens.
If you look down the carb and slightly open the throttle and nothing comes out the squiter,......probably float level set to low. set it back to the factory setting.

EDIT: check squirter pump while you have the top off of it.
 
Got just a little dribble at best. I will reset the float. What do you think about the plugs? I cleaned best I could, seems to idle fair enough (see pic).

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clifftt said:
You mean accelerator pump? I will check it, it was replaced from the kit.
Click to expand...
Yup never know if the squirter pump (accelerator pump) is set to high, float set to low or that little plastic tube is trying to fall off.
Just look it over closely when you get the top off of the carb. The problem is in there somewheres.

It easy to change the jets while you in there..........But i bet you find the problem elsewhere inside there.
 
I'm not sure the transfer slots apply to AFB do they?
 
Cudafever said:
I'm not sure the transfer slots apply to AFB do they?
Click to expand...

Carters have transfer slots just like Holleys, I think it's a necessity in pretty much any fixed-venturi carb...?

If you had a dual-plane intake with the same problem (carb too rich on one side) it would show on cylinders 1, 4, 6 & 7 or 2, 3, 5 & 8 because the plenum and runners are split to create even intake pulses based off the firing order of a V8.

See if it'll take more initial timing, what kind of vacuum is the engine pulling at idle now? Also might want to check valve lash just to rule that out.
 
Thanks to all your replies. First chance in two weekends to mess with this.
Engine is pulling 15 to 15 1/2 lbs vacuum at idle. I reset the valve lash after breaking in the engine. I have set the timing with the vacuum hooked various times between 32 and 38*.
I checked the floats, they were 8/32", I moved them to 9/32 (spec is 7/32"). I also have the float drop set to 3/4" like the factory manual shows.
The engine still idles noticeably rough, idling around 850 warm. I see the primary butterfly is not completely open, held a little closed by the heat thermostat in the intake manifold (see picture). It clears up a little when I pull the choke fully open (see the second pic). Maybe the choke thermostat is not pulling the butterfly fully open??What should be the normal position of the choke butterfly after full warm up?

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Your timing cannot be set with vacuum on the can. It must be removed. It should be around 34-36 total by around 2500 or so. Then the vacuum can needs to be hooked to a ported vacuum source.

But total on a street car is not terribly important. You need to have around 20 degrees initial and 14-16 mechanical. This is without the vacuum can hooked up. Once you get the initial and total right, hook the vacuum can to ported vacuum and you're done.
 
Ok #1
See that choke pull off on the right lower portion of the picture? It should be pulling the choke blade open.
Is there vac to that diaphragm, is it pulling on the linkage.
When it's cold and the choke coil is strong, the choke pull off can only pull it out so much, as the choke coil warms(eng warms up) the coil gets weaker and the choke pull off, pulls it fully open. like your finger is doing in the 2nt picture.
If the eng is running, in that 2nt picture, the choke pull of is NOT working.
You are still running rich, because you choke is not working properly.(not opening up fully)

Once you get your choke pull off to work, there is instructions on how to set that up as well.
 
^^^ Cudafever is right, when warm and running the choke should be completely open like it is in the pic of you holding it open. The fact that your choke pull-off vacuum can isn't working could point to a vacuum leak there which could certainly cause a rough idle. 15" of idle vacuum is pretty good though.
 
The choke pull off only opens the choke so much (not all the way)
It is designed to open the choke just a little when the engine fires up.
The rest of it opening relies on the bimetal spring as the engine gets hotter, and sometimes they don't open all the way due to a plugged up crossover in the intake. (usually older OEM manifolds)
The other reason is that the bimetal spring that controls the choke is bad.

An electric choke conversion kit for that would be nice to have.
 
TrailBeast said:
The choke pull off only opens the choke so much (not all the way)
It is designed to open the choke just a little when the engine fires up.
The rest of it opening relies on the bimetal spring as the engine gets hotter, and sometimes they don't open all the way due to a plugged up crossover in the intake. (usually older OEM manifolds)
The other reason is that the bimetal spring that controls the choke is bad.

An electric choke conversion kit for that would be nice to have.
Click to expand...
The bottom of the manifold was opened up when at the machine shop and all the crud cleaned out. Man, it was packed! I'll explore my choke options.
 
See if it runs any better if you disconnect the choke pulloff and plug the vacuum port that feeds it and fiddle with the choke so it manually stays fully open. I'm willing to bet the vacuum diaphragm is torn.
 
First chance to work on this problem this week. I changed the right bank of spark plugs, now all eight look clean. Timing set, per RRR's post with vacuum disconnected.
Warmed up the car, still idling rough. The bimetallic choke never fully opened, so I wired it full open. Engine is warm by this point. At various stages, I disconnected and plugged the choke pull off, the pcv hose, the distributor advance hose, and the brake booster hose before the check valve. I was really hoping to find the problem somewhere here, but nothing changed.
When I give the throttle a quick flick, a strong double jet of fuel shoots out, but the engine stumbles.
The engine runs best when the idle adjust screws are full open (rich). But the accelerator pump, when hit, still causes the engine to stumble.
By now, the engine has been idling for about 15 minutes. I pull a few of the spark plugs and they're clean as a whistle, not fouled at all.
To recap, the engine idles rough and bogs when the throttle hits. At this point, I'm thinking about replacing the carb. Thoughts welcome.
 
Are there any holes drilled through any of the butterfly plates? If yes, then they all need to be closed up and then go here;
AJ's guide to Transfer Port Synchronization

After that is done, reset the pump linkage, to initiate a stream at the slightest, most gentle throttle-arm movement.A stream not a dribble or a hesitation, and all gas no air!
What the T-port sync attempts to achieve is a synchronization of the transfer ports to what the engine needs.These transfer slots are your main low-speed transitioning circuit. The mixture screws that you can play with, just fine tune it for idling.These transfer slots are the only way to get fuel into the airstream until the airspeed through the boosters starts to pull fuel for the main metering circuit.They have to be timed pretty accurately.
If someone has drilled the plates for a big camshaft, this will totally mess up the sync. If the initial timing is too much, or too little, this may totally mess up the sync. If the butterflies are too far closed then the engine will go immediately lean on tip-in and stumble. If the butterflies are way too far open then idle vacuum may partially dry them up and tip-in will again be lean. And if they are just a little to far exposed then the engine will idle fat. It may just be rough, or it may have a miss, and messing with the mixture screws will give little to no relief.
But if there are no holes in any of the plates then the secondaries need to be closed up just short of sticking, and the brake-booster line clamped shut, the PCV proved correct for the application, and then the T-port sync still has to be performed! When done, un-clamp the booster line, and after a slight sag as the booster comes on line, the idle speed and quality should return to that pre-unclamping.
When all else fails, crank up the float level 1/16" and start capital-A,All, over.

Bolting on a new carb may or may not solve the condition, depending on what is causing the condition. So
the T-port sync is job one! Then cuz the butterflies may find a new setting, the pump-shot needs to be revisited.
Good luck!
 
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You may be lean now.......let the choke be half way closed and blip the throttle. If the stumble improves......Its lean

aka may need bigger jets or a different metering rod that does the same thing.
 
AJ/FormS said:
Are there any holes drilled through any of the butterfly plates?
Click to expand...

I pulled and rebuilt the carb and am pretty sure there were no holes drilled. I'm going to pull the carb off this week and look.

Cudafever said:
You may be lean now.......let the choke be half way closed and blip the throttle. If the stumble improves......Its lean
aka may need bigger jets or a different metering rod that does the same thing.
Click to expand...

i did blip the throttle with with the choke partially closed, but it still stumbled.
 
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