48 ford hard to startmr 48

O

ora masters

Well-known member
my 48 ford with 60,000 miles has never bin overhauled it had a bent valve stem when i got it two years ago after a lot of work and help from ford barn got that fixed it starts first time over when cold after that a lot of cranks have ruled out vapor lock with electric pump this morning checked the compression all 8 were 75 pounds engine was cold it cranks good when hot any help would be great thanks ORA
 
ora masters said:
my 48 ford with 60,000 miles has never bin overhauled it had a bent valve stem when i got it two years ago after a lot of work and help from ford barn got that fixed it starts first time over when cold after that a lot of cranks have ruled out vapor lock with electric pump this morning checked the compression all 8 were 75 pounds engine was cold it cranks good when hot any help would be great thanks ORA
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Check battery voltage, should be over 6.3 Check voltage at the coil wire from the ignition switch to the coil. With the switch on and the points open you should have over 6.0 volts. Measure on the coil side of the resistor with the points closed and should be around 4.0 volts, with 3.5 volts it should start fairly good but at 3.0 volts it will be hard to start. You can tell when the points are closed by the lower voltage readings. When the points are open the side of the coil going to the points is just like hanging in the air, when the points are closed it completes the positive side of the battery which is grounded to the engine. MAKE SURE you don't leave the switch on over 5 minutes or you can melt the coil if the points are closed. If the engine and coil are hot and it don't start this is typical of all old Ford coils, send it to Skip Haney in Florida to have it rewound this solves the problem. G.M.
 
If the battery checks good and the voltage on the coil is good per GM, pull a plug wire and check the quality of the spark holding the wire slightly above the head (might want to use an insulator around the wire where you're touching it). The spark should jump and be a bluish color, not yellow. Yellow indicates low voltage.
Then check for gas because a bad economizer valve in the carb can let the gas drip out of the bowl.. Takes a lot of cranking to fill the bowl again. Sometimes I pour a little gas down the carb to see if it will start right away to determine if I have a fuel problem. Others are more expert than I am on these problems, but these are easy checks to do. Hope it helps.
 
Put a diode wire from starter wire side of starter relay to coil and it will start hot or cold. This will put 6 volts to coil for starting when you let off of starter button the diode will keep Voltage from going back to starter. Hope this will help you.
 
thanks GM i mailed the original coil to skip this morning i had already taken it off and put a new barrel coil on did not help so i am not sure coil is my problem
 
thanks brooks for reply i am an old model A nut i know model A but nothing about any thing past 1932 what is a diode wire and were do i get one draw me a picture i am not real smart when it comes to electric wiring
 
Try a jump wire from the battery Neg to the coil see if that helps as it will indicate bad connection/ contacts I,N,G etc. Swap /tighten condenser . swap the rotor .check the spring loaded contact inside the disrubtor .Ted
 
brooks got your email +could not bring up picture will get diode from radio shack and get my buddy to hook it up thanks
 
got your email still cant bring up picture i am not real sharp om this thing next week will find someone to put diode on thanks Ora
 
If you have the new round coil for a 6 volt car,
" The resister is NO longer needed."
You could be loosing 1 -1.5 volts, and try a newer ign switch.
Those ign switch's are to old.
 
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