engine won't fire

W

wbs

Senior Member
hello-need advice---timing method:with spark lever all way up and while making sure number 1 cyl on compression cycle, and while watching piston rise, reach tdc, then let piston go down 1/8" by visualization and by probe -then set the points so they just open---has excellent visible spark
car has excellent compression by feel
to rule out carburetor prob:
tried putting tbspoon gasoline in air intake of carburetor, no firing
tried putting tblspoon gasoline in no. 1 cyl , no firing
open to ideas thank you
 
Which coil was working from the commutator? Try a shot of some starting fluid at the carb while cranking.
 
Clean your points and check that you have voltage at the points. Easy way is with power on, points closed, open and close by hand if they spark you have voltage there (6 or 12 volts only at the points). The points need to be set to just be ready to open the at the the setting that you were using for just past top dead center.

ALSO, make sure you are wiring the plugs to the terminal that you have set for No 1. Unlike many cars that came with a distributor, Model T's DO NOT have a dedicated position for No 1 when adding a distributor. Check your rotor position and wire 1243 from there. Make sure you are timing on compression stroke, both valves are closed.
 
A distributor on a model T engine likes to be set at 15 BTDC....
Snyder makes a timing tool to get this perfect by screwing the tool into the spark plug hole...
 
thanks to red and bubba--if you look at the face of a clock, each minute past 12o'clock is 2 1/2 min past 12 oclock is 15 degr-i think i 'm at that and i know i was on comprsn as i felt the piston trying to force my thumb off spark hole-it gave a good spark-------if i could just separate a carb prob vs ignition prob it would a big step- i think i'll try putting a tsp of gas or carb cleaner in all 4 cylinders and see if that works better than just 1 cyl - i'll also look at the tool that bubba suggested--
 
No way I am going to nor recommend anyone to set spark to 15 BTDC (before top dead center)! That would be a great way to break your arm hand cranking your T and the kick back on the bendix would not be good ether.

15 BTDC is about what the Model B front cover has built into it for timing (might be 17 deg's).
 
redmodelt said:
No way I am going to nor recommend anyone to set spark to 15 BTDC (before top dead center)! That would be a great way to break your arm hand cranking your T and the kick back on the bendix would not be good ether.

15 BTDC is about what the Model B front cover has built into it for timing (might be 17 deg's).
Click to expand...


Your are correct , 15 wouldnt want to hand crank. I assumed he was using a starter.
Did i ever tell ya about the time i broke my thumb trying to hand crank a model T ???
Havent had a hand crank in the garage since!!:eek::)
 
thanks for feed back- i thought that the spark retard [15 degrees or 2 1/2 clock minutes]] was the same for both hand crank or motor cranking. yes, no? the thought being that being that the starting revolutions are slow so you want the piston on its way down when combustion occurs so taht it will continue its downward direction------if combustion occurred when piston ascending, the rotation would be reversed[kick back]---that is what i have done--set the spark to occur when the piston has passed top and is slightly down
 
thanks to all especially red and bubba who gave multiple responses---i did check the firing order and it was 1243 ccw while looking downon the distrb. i did not make any changes to carb or igninition but did spend the last 8 hours getting the starter working. theni held the starter down for 2 or 3 complete revolutions and the engine fired . i did not try to hand crank after.
i have no explanation why it woud not fire by hand crank but the car had not been run in 9 mos. and i have pull start lawn mowere that does the same thing after being idle for a few months--i have to pull it about 10 times then wait 20 mins , give ita a pull and it starts.
 
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