manifolds

murrie

Member
any one know why when i removed intake/exhaust manifold,raw gasoline was in one of the chambers?never seen this before thanks
 
Stock updraft carburetor or downdraft? If updraft then the only way I know of is if the car did not start after choking it. Otherwise the intake manifold and exhaust manifold get hot enough to evaporate any raw gasoline.
 
Why did you remove the manifolds, and what did you do prior to pulling the manifolds?
If the engine wasn't running & up to temp, you would be pulling fuel into a cold engine when choking. What about when stopping? When you kill the ignition, engine rotation will still cause fuel to be pulled into the intake
 
the engine would fire and not run.pulled manifolds assuming the intake was leaking and not pulling gas up to run,plus exhaust manifold was leaking.i never got engine to run.i have got good spark at points and fuel to carb. but cant get it running.
 
It take 3 things to make an engine run …
1 Compression
2 fuel
3. Fire at the right time

I would say you have fuel unless you have a stuck valve issue on one or more of the cylinders that is making it hard to start . it sounds like it’s pulling the fuel mixture. Check your correct timing and compression on all cylinders and troubleshoot methodically what the issue is.
Keep in mind the 3 thing above including fire at the right time .
Make it run !
Larry Shepard
 
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the engine would fire and not run.]pulled manifolds assuming the intake was leaking and not pulling gas up to run,plus exhaust manifold was leaking.i never got engine to run.i have got good spark at points and fuel to carb. but cant get it running.

This is a very common problem.

If engine starts and runs a second or two then stalls.

Most likely cause is failure to open the GAV ONE turn before starting the engine.

This is covered in the Model A Owners Manual.



If temperature is 10 or 20 below zero then More GAV may be needed to keep engine running.
 
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Spark at the points is not a guarantee that there is spark at the plugs. Spark at the points is indicative that the low voltage ignition is working, but does not give you any info about the hi-voltage ignition. Check these slides for some things to look at.
 

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Spark at the points is not a guarantee that there is spark at the plugs. Spark at the points is indicative that the low voltage ignition is working, but does not give you any info about the hi-voltage ignition. Check these slides for some things to look at.

Great presentation, Bob
 
Spark at the points is not a guarantee that there is spark at the plugs. Spark at the points is indicative that the low voltage ignition is working, but does not give you any info about the hi-voltage ignition. Check these slides for some things to look at.

Great presentation, Bob

We call the "High voltage trails" on the distributor cap and body "carbon tracking in this neck of the woods. Check the coil for carbon tracking also.
 
alright gentlemen,did the bob bidonde spark in the dark test,great idea by the way, and found bad resistor.replaced, thet reinstalled straight manifolds,gasket, and still no gas to cylinders.removed spark plug,poured tiny amount of fuel in plug hole,engine fired.i understand i'm not getting gas to combustion chamber,but i dont know why i'm not.good flow of gas to carb.i'm new to this,why no gas from carburator.thanks again looking forward to hearing from yall.
 
Bad gas flow to the carburetor could be several things. The screen filter in the carburetor or the filter on the firewall may be plugged with sediment which is usually the cause.
 
alright gentlemen,did the bob bidonde spark in the dark test,great idea by the way, and found bad resistor.replaced, thet reinstalled straight manifolds,gasket, and still no gas to cylinders.removed spark plug,poured tiny amount of fuel in plug hole,engine fired.i understand i'm not getting gas to combustion chamber,but i dont know why i'm not.good flow of gas to carb.i'm new to this,why no gas from carburator.thanks again looking forward to hearing from yall.

Bad gas flow to the carburetor could be several things. The screen filter in the carburetor or the filter on the firewall may be plugged with sediment which is usually the cause.

He mentioned he is getting good gas flow to the carb.

I didn't see it mentioned, Did you ever checked your compression?
 
Also, check to see that the gas line into the carb is not too long and blocking the fuel flow. The ferule should be only 1/8 inch or less from the end of the fuel line.
 
What resistor? Do you mean condenser?

You can check for adequate fuel to the cylinders by turning the ignition key OFF, and then choking the carb by holding up on the choke rod while engaging the starter for about 10 cylinder compressions. Have your plug removal tools handy and quickly check the 4 plugs to see if they are fuel soaked.
 
got it fixed.took carb off of other car to eliminate carburator it worked fine.after that took manifolds off,and got new manifold i had.used copper gaskets,other manifolds were warped. fired right up.oh well learn by making a mistake.thank everyone for you help.
 
Y-Blockhead, thanks for the compliment. In my presentations, I consider that the audience has people newly exposed to the antique car hobby and the Model "A", so I try hard to avoid using hobby jargon. You experienced and wise senior hobbyists know what I am talking about.
The slides I posted are the tip of the iceberg when it comes to the ignition. Yes, I do recommend checking for hi-voltage leaks in the dark on other slides.
 
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