missing on #1

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DAN CHALMERS
Posts: 48
Joined: September 30th, 2008, 5:50 pm
Body Type: 82B
Model Year: 1931
Location: southwest harbor, maine

missing on #1

Post by DAN CHALMERS »

put a rebuilt 4 cyl. in a 32 BB. Not firing#1 cyl. . compression 82 lbs., new cond., dist cap, rotor, points, bushings on dist shaft,new cam lobe, new pts., new plugs, plug coppers, rebuilt the carburator, chked pts. gap and timing over and over, plug gaps, inter changed plugs, and still weak. If manifold gasket leaks would it not show on compression test? I must be overlooking something simple. Please help me feel embarressed. :oops:
I know its 32 but still Ford 4 Danny
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spectria
Posts: 1874
Joined: May 15th, 2008, 9:53 pm
Body Type: Mail Truck, Stakebed
Model Year: 1931
Location: Quincy, Ca.

Re: missing on #1

Post by spectria »

DAN CHALMERS wrote:put a rebuilt 4 cyl. in a 32 BB. Not firing#1 cyl. . compression 82 lbs., new cond., dist cap, rotor, points, bushings on dist shaft,new cam lobe, new pts., new plugs, plug coppers, rebuilt the carburator, chked pts. gap and timing over and over, plug gaps, inter changed plugs, and still weak. If manifold gasket leaks would it not show on compression test? I must be overlooking something simple. Please help me feel embarressed. :oops:
I know its 32 but still Ford 4 Danny
To begin, how do you "know" #1 is not firing?

Manifold gasket would not affect compression test. An air leak around #1 intake port would lean that cylinder out more than the others, spray wd 40 or B12 carb cleaner around intake port with engine running, watch for change in engine speed. ( careful, flammable ).
Good compression, plugs good, wiring intact, should expect to see #1 operate as usual.
Carb mix, distributor timing, points, airflow, all should affect all cylinders, so if there were a problem there it would do the same to the others.
Dave in Quincy, Ca. I love Pics!!!! Post them All!!! :)
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gunmetal 2
Posts: 222
Joined: April 1st, 2013, 12:51 pm
Body Type: 82-A
Model Year: 1929

Re: missing on #1

Post by gunmetal 2 »

Take the wire going to #1 plug and see if you get spark. If you do go to #2 and see if you got spark etc. If all cylinders have spark you my have a bad spark plug, to check that take plug out with the wire connected and see if you got spark 1,2,3,4. Try this and give us a up date what you find.
SHELBY MESSER
Posts: 752
Joined: March 9th, 2009, 8:06 pm
Body Type: 75-A
Model Year: 1930
Location: Sacramento, Ca.

Re: missing on #1

Post by SHELBY MESSER »

Danny, You said that you replaced the distributor cap :?: Did you replace the distributor body? If so or :) not try a different body. Some times they are bad or get bad. Seen this happen before :shock: Shelby, Louisiana.
DAN CHALMERS
Posts: 48
Joined: September 30th, 2008, 5:50 pm
Body Type: 82B
Model Year: 1931
Location: southwest harbor, maine

Re: missing on #1

Post by DAN CHALMERS »

easiest way for me is to short out the plugs with a screw driver and see which one isn't making a difference. 4 and 3 nearly kill the engine , 2 makes considerable difference and 1 just arcs on the cyl. head . I have rotated plugs replaced with new, and yes I did replace dist. body as well.compression is 82 on 1, 77 on 2, 75 on 3, and 77 on 4.
Is it possible to have a crack in water jacket and still have good compression? Plug is fouled but appears to be unburned gas. I'm confused. :?: Danny
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spectria
Posts: 1874
Joined: May 15th, 2008, 9:53 pm
Body Type: Mail Truck, Stakebed
Model Year: 1931
Location: Quincy, Ca.

Re: missing on #1

Post by spectria »

DAN CHALMERS wrote:easiest way for me is to short out the plugs with a screw driver and see which one isn't making a difference. 4 and 3 nearly kill the engine , 2 makes considerable difference and 1 just arcs on the cyl. head . I have rotated plugs replaced with new, and yes I did replace dist. body as well.compression is 82 on 1, 77 on 2, 75 on 3, and 77 on 4.
Is it possible to have a crack in water jacket and still have good compression? Plug is fouled but appears to be unburned gas. I'm confused. :?: Danny
Yes, but this shouldn't cause the problem you are having.
Does the #1 plug smell of fuel on plug? Maybe a huge buildup of fuel in #1, repeatedly fouling the plugs.
Prop the carb and choke wide open, ignition off, #1 plug out and crank the motor, see what comes out the #1 plug. Safer to put the compression test hose in the plug hole and cover opening with heavy White cloth.
Your shorting method proves ignition to each plug. Great if you could post a pic of the #1 fouled plug.
Dave in Quincy, Ca. I love Pics!!!! Post them All!!! :)
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BrianT
Posts: 254
Joined: October 25th, 2013, 8:27 am
Body Type: 82A
Model Year: 1929
Location: San Diego, California

Re: missing on #1

Post by BrianT »

DAN CHALMERS wrote:easiest way for me is to short out the plugs with a screw driver and see which one isn't making a difference. 4 and 3 nearly kill the engine , 2 makes considerable difference and 1 just arcs on the cyl. head . I have rotated plugs replaced with new, and yes I did replace dist. body as well.compression is 82 on 1, 77 on 2, 75 on 3, and 77 on 4.
Is it possible to have a crack in water jacket and still have good compression? Plug is fouled but appears to be unburned gas. I'm confused. :?: Danny
The the B engines are well known for cracked blocks the plug could be water fouled, another possible cause is a water leak from the steam hole into the cylinder, have someone crank the engine with the key off, and watch for fine bubbles rising in the radiator, or leave out the plugs and let it sit for a while crank it and watch for water vapor from #1, if OK then look into # 1 and check that either valve is opening, ----- tell us more about the rebuilt engine, ---- In addition install a vacuum gauge and let us know what you see.
RustydoubleA
Posts: 108
Joined: June 18th, 2014, 10:22 pm
Body Type: express
Model Year: 1930
Location: N. Calif.

Re: missing on #1

Post by RustydoubleA »

SWAP OUT THAT SPARK PLUG!!!!!!!!
ModelAkid
Posts: 478
Joined: June 3rd, 2013, 6:15 pm
Body Type: 186-B stake
Model Year: 1931
Location: LHC Arizona & UP Michigan

Re: missing on #1

Post by ModelAkid »

In the first post Dan said he tried switching the plugs around. This is a most interesting problem!
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spectria
Posts: 1874
Joined: May 15th, 2008, 9:53 pm
Body Type: Mail Truck, Stakebed
Model Year: 1931
Location: Quincy, Ca.

Re: missing on #1

Post by spectria »

A broken lifter or flat cam could cause this misfire, you could still get good compression. A valve not opening could cause this. Likely an exhaust valve.
Remove the valve cover and check lifters...
Dave in Quincy, Ca. I love Pics!!!! Post them All!!! :)
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ModelAkid
Posts: 478
Joined: June 3rd, 2013, 6:15 pm
Body Type: 186-B stake
Model Year: 1931
Location: LHC Arizona & UP Michigan

Re: missing on #1

Post by ModelAkid »

The easy way to see if the valves are working is to just look at them through the spark plug hole. If you can't see one put a wire through the hole, on top of the valve then crank the engine to see if it is going up & down.
KimVanOrder
Posts: 753
Joined: August 11th, 2013, 4:25 pm
Body Type: 82-A Platform
Model Year: 1928
Location: Hamilton, Mich.

Re: missing on #1

Post by KimVanOrder »

Back to basics...... How do you know it is #1 that is missing?
KVO
Dec. '28 AA
ModelAkid
Posts: 478
Joined: June 3rd, 2013, 6:15 pm
Body Type: 186-B stake
Model Year: 1931
Location: LHC Arizona & UP Michigan

Re: missing on #1

Post by ModelAkid »

DAN CHALMERS wrote:easiest way for me is to short out the plugs with a screw driver and see which one isn't making a difference. 4 and 3 nearly kill the engine , 2 makes considerable difference and 1 just arcs on the cyl. head . I have rotated plugs replaced with new, and yes I did replace dist. body as well.compression is 82 on 1, 77 on 2, 75 on 3, and 77 on 4.
Is it possible to have a crack in water jacket and still have good compression? Plug is fouled but appears to be unburned gas. I'm confused. :?: Danny
A crack between the cylinder and water jacket is beginning to seem likely. I do not think a hairline crack would affect compression noticeably but any water getting in the cylinder could foul the spark plug. When you put in a clean plug, does it fire at first but then quit? I would pull the head and closely examine it as well as the block and the valve chambers. Like BrianT said, the B engines seem to be more problematical for issues like cracks than A's are. Maybe Ford tried to make the "walls" too thin. Maybe they were not up to the increase in compression and HP.
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