carb cleaner

[pj the dj]

Hi i'm new to the barn and need advise. Have '30 coupe and it just started to run crappy. I bought a bottle of "guaranteed to pass" to pour in the gas tank and it says it's used to clean valves and injectors. But, i'm afraid to pour it in. Should I not do it? What would clean the carb short of me taking it apart? I never had a problem until I followed some ones advice and took the air maze off. Thanks for any advice.

[markyb]

I'm new to Model A's, but from what I've read, some carbs have modified jets or inlets to compensate for the reduced air flow of air filters. Removing the filter probably created yor problem, not a dirty carb

[Brentwood Bob]

Go thru some diagnostics. First, open the plug on the bottom of the carb,and see if you have a good flow of gas. If that is obstructed then unhook the gas line at the carb and see if you have good flow. I suspect dirt in the gas. Start there. Don't use the fixall, pour in the tank stuff.
Good time to learn how to clean the jets.
Bob

[ctvpa]

There are several fuel filters in the Model A. One in the gas tank, one in the fuel line, and one in the carb. Be sure they are all clean.
Please don't put anything in the tank.
Many use marvel mystery oil in the gas (controversial as to if it does anything), but it will not correct this problem.

Also check your gas tank cover, loosen it. Sometimes the vent gets clogged. Also where is your GAV valve set (the valve in front of the passenger seat). It should be 1 full turn to start, then it should be adjusted to where the engine runs well. For some, they can run closed, Mine runs best about 1/4-1/2. Many will argue this, but as a long time Model A'er told me, If there is a adjustment, Henry meant it to be adjusted.
Good luck

[Aok]

The old tank cork floats were I think varnished to seal them so read the ingredients if it has something that will eat the varnish it will sink your float.

[FL&WVMIKE]

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Originally Posted by Aok

The old tank cork floats were I think varnished to seal them so read the ingredients if it has something that will eat the varnish it will sink your float.

Aok ......................
The corks were coated with shellac to keep the gasoline from getting to to cork. Alcohol is a solvent for shellac. The new (corn) gas has alcohol in it and disolves the shellac, allowing the cork to soak up the gasoline.
Those cork floats worked for decades, before the new gasoline came along.
MIKE

[Aok]

Mike, Thanks for the correction , I found out the hard way car was running poorly I was thinking water in gas put in some dry gas which has alcohol in it. I installed a new neoprene float and gas gauge is working again

[SeaSlugs]

Originally Posted by pj the dj

Hi i'm new to the barn and need advise. Have '30 coupe and it just started to run crappy. I bought a bottle of "guaranteed to pass" to pour in the gas tank and it says it's used to clean valves and injectors. But, i'm afraid to pour it in. Should I not do it? What would clean the carb short of me taking it apart? I never had a problem until I followed some ones advice and took the air maze off. Thanks for any advice.

hmm
well lets see here: car was runnign good till you took off the air maze AKA a small air restriction. Since the engine cylinders cant adjust the amount of air they pull in and expell per stroke is going to stay the same.

an engine needs 3 parts to work: air, fuel, and spark. Since air and fuel both come from the carb, if you restrict one, the other has to give (or atempt to) the rest of the amount of air it sucks in per stroke.

Meaning in a nut shell:

With the air maze attached someone had to lean out the carb or it would suck too much gas causing it to run rich.
When you removed the maze the vacuum dropped so now it pulls less fuel so now your mix is too lean and not enough fuel so low on power, missing, coughing weird would be symptoms.

If you have ever messed with a pushmower and put your hand over the top of the open carb to restrict airflow it will flood the engine as its trying to suck air thru the fuel system (since it too is gravity fed just like an A)

Thats why if your push mower is hard to start and runs like crud check your air filter - usually their caked with dirt and oil and cant breathe.

A model A engine is nothing more than 4 lawnmower engines put together fed from one carb

so to answer your question: no carb cleaner will not help