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Ford flathead - Engine 59ab

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Hi everyone!



I have a 1946 Ford super deluxe with engine 59ab. I´m having a problem with this engine...I think that it only works with 6 cylinders...


I put new parts:


-carburetor 94 two barrels



-complete distributor that I bought on the internet (ebay)..the seller indicates that  it was only necessary to install. All adjustment´s already done



cap (with crab style). I checked out that the firing order is the same like 1946-1948 engines



The question is that the engine doesn´t work right...the 5th and 8th cylinder seems died..! They are one the driver´s side flathead, at the ends..! I confirm that they have electricity on the plugs...I pulled out the plugs and I saw them work. The cylinders have compression .... The valve ares working and without plugs I saw the cylinders and valves clean!  When the engine is working I disconect the wire of 5th or 8th (or both at same time) and the engine works without any difference. In the all others cylinders, if I disconnect one wire, the engine looses power, easily understand that they are working ok! The 5th and 8th...not...


I don´t know what could be the reason for that...I checked again order or wiring with distributor and they are right!.


Could be the carburetor? not enough fuel to the extreme of the flathead? This make sense? I already adjust the two screw air mixture...but without differences...


Someone have one idea what could be the reason for that??


Thanks a lot





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How did you check the compression? If it is the same on all cylinders of the engine and the firing order is correct  1 5 4 8 6 3 7 2 then it should run unless there is a blockage inside the manifold, either intake or exhaust. Blockage would seem the next thing to check for.

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I didn t check the compression with specific tool....I only take of the plugs, put the engine runing and compare the air pressure between cylinders...I didn t see diferences...


I realized that when the engine is cold, at the first start I push the cold button, and if take off the wire of the plug of 5th or 8th, I feel the diference the engine looses power....but when the engine warm, nothing happens at 5th or 8th cylinder.......the pressure stays at 15 when the engine is cold...and almost zero when hot....this can change the valves function? (Intake, exaust).

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Try changing one of the failing spark plugs with a working spark plug. Sometimes a spark plug will work outside of the engine, but will not work under compression.


Is the spark on cylinders 5 and 8 as strong as it is on the other cylinders?


The low oil pressure  could  be alright. It should be checked with a mechanical gauge to  be sure. If the engine does not make knocking sounds it is alright to run the engine and drive the car.

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