Dropped oil pan - findings / question

[AAzz44]

Taking advantage of this winter and doing some maintenance on my A. I dropped the oil pan and wanted to run a few things past the group.
I noticed what looked like carbon build up near the front. Is this possible? I added photos to share.
Also pulled the spark plugs (which I replaced about 3 months ago) and here is how they look. Lots of carbon build up.

I just purchased this car about 6 months ago and noticed it always seem to be rough idling and lacked power. Been trying ti find out why since than.

Thoughts on why you see and where I should go next?
As info, oil pan was actually cleaner than expected with very little sludge build up.

Thanks
Mike

[AAzz44]

Forgot the pictures.

[J Franklin]

Crankcase looks fine to my eyes. Plugs show a too rich mixture. You might want to check some clearances while the pan is off, but it looks like it hasn't run much since last look.

[WHN]

What spark plugs were in your car?

Could be a couple of things. Plugs, carburetor and how it is adjusted, and the timing.

Had a similar problem 20 plus years ago. Turned out to be the spark plugs.

Enjoy.

[Ernie Vitucci]

What Brand and Number Plug are you running? Many folks run Champion W-16y or W-18y. Others will have other recommendations depending on experience and where they live...Ernie in the Wilds of Arizona

[Ed in Maine]

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Your description of operation could be from many different things. When you don't know, it is time for a general cleaning and tuneup as follows:
1. Clean the carburetor and flow test jets to be sure they are sized properly. If the Main Jet is too big, the car is going to run rich. A good setting is 155 ml/min.
2. Check to see that a leaking exhaust manifold connection to the tail pipe is not allowing exhaust gases to get into the inlet of the carburetor. Carefully place your hand on top of the carburetor inlet with your fingers pointing down thereby preventing the exhaust gases from going straight into the inlet. If Idle improves, reseal this connection. A good setting for the idle jet is 46 ml/min. and the Compensator Jet is 140 ml/min.
3. Retime the car and when driving strive to set the timing lever for best performance.
4. Set the GAV (Gas Adjusting Valve inside the car) for best performance often. Too far open and you are going to be running rich.
5. Clean the plugs and install new points and condenser
6. Have fun driving your Model A. Good luck, Ed

[AAzz44]

WHN & Ernie - I am running Champion W16Y’s.

[AAzz44]

Ed - I was thinking the carburetor might need to be looked at. My last resort was to pull and clean it.
2. I can tell you I checked for exhaust leaks and I am good there.
3. I did retime the car and no changes.
4. Weird thing here is I can run the car with the GAV closed. I tend to crack it open about a 1/4. Also, I noticed the GAV is really loose, as in it has a ton of play in it. Is this normal?
5. Plugs are cleaned and will also be checking distributor.

Thanks for the advice. I will let you know what I find.

[gdmn852]

Hello, if it runs well with the gav closed, I would suspect float level is off , that would definitely allow it to run rich. Check what carburetor you have some still have the original cast iron Zenith, others have been changed to die cast type. A search on the barn will give some info on the carb. I would also suspect the needle valve may need attention too. I would think your lower engine looks good, seems to have shims in rods that is good. Doesn’t look like a lot of slugh build up .

[WHN]

Originally Posted by AAzz44

WHN & Ernie - I am running Champion W16Y’s.

Those plugs are in our car. I would get new ones and also new points.

I think you carburetor needs to be looked at. Our GAV setting, when car is warmed up, is at 1/4 turn, counter clock wise.

Please don’t go crazy taking things apart. I don’t think you have a big problem here.

[Gene F]

I agree with WHN. It is either spark plug choice, or something in the carb. I'd suspect the float is a bit high.

[AAzz44]

Thanks for the advice. I will check it out. I ordered a few tools to check the float and will respond back to what I find.
Thanks

[P.S.]

My guess- The carb has repro jets that are too big, causing rich mixture. If it runs good with the GAV closed, then run it that way for a while and check the plugs again. Maybe that's all you need to do.

[rotorwrench]

If it's been setting a long time, the rings may be stuck or valves may be sticky. Marvel Mystery oil blended in the fuel per instructions will help loosen things up. Pour bit in each cylinder and let it sit for a while. It will soak through the rings and help dissolve the crud in there. The rings & valves will eventually unstick and function as good as normal wear and tear will let them.

With the pan off, a person can check the clearances on the mains and de-shim per a normal procedure if necessary. The valve cover has to be off to get to the center main nut. I don't know if the OP wants to go this far but it is one of the things that model A owners need to consider doing now and then when mileage or condition is in question.

[jeepguy1948]

If you are by chance using an air filter that will cause the engine to run rich. The updraft carb will simply not tolerate an air filter (I learned this from personal experience).

[PC/SR]

Looks good and the plugs are a little rich but not outrageous. Not to be disrespectful, as a 6 month owner you may be expecting too much? Comparison? Rough idle is usually carb, could be ignition. Could be a lot of things, do not over analyze things.