so i picked up an old 50 f1, mostly all the wiring was pretty well chewed up, but still in tact. I've gone through and replaced mostly everything that is of importance for me getting this v8 flathead to fire, got combustion, replaced points and ive got good spark.... however... ive got a spark at the carbeurator.. ive gone through this truck for a week now, block is grounded.. ive basically tried to eliminate everything and just run grounds and then power the starter right off the battery... still getting this spark at the carbeurator.. anybody have any clues where I should be looking???? got a nice thick ground cable to the block and to the chassis, but have spark jumping at the carb.. feel like it should be easy enough to find, starters reading about3.5a when i run power to it.. starter does sound somewhat weak,... help!
I would trace the wire thats causing the problems and diagnose the wiring issue with a backwards approach for starts maybe you will see something you didnt catch.
If you are getting spark when cranking it it could be bad spark plug wires, the lead to the coil or even bad plugs. If that does not work. Disconnect everything run a lead from the battery to the resister block for the coil. Put a heavy duty switch inline so you can shot it down. Pos battery cable to the starter solinoid and jump the solinoid to start it.
sparks at the linkage when you give it gas it starts arcing . spark plug wires are pretty ate up but i know theyre not touching anything they shouldnt be
hahaha.. i did also find some old bondo covering up a hole in the intake... got somebody by for awhile i suppose but one more little setback in bringing another old flathead back to life
Got to be bad plug wires. If they are internally broken, they'll look for something else to ground to.
Yea its most likely your plug wires popping the block and grounding off your linkage and your firewall. Replace the wires and see if that gets you by.
chewed up plug wires don't have to 'touch anything'. That's a lot of voltage and it will take the easiest route to ground. High-voltage wires (which is what spark plug wires are after the coil does its job) will jump anywhere it can. "Chewed up"???? Time for replacement - you get a spark near any fuel source and you'll have more than chewed up electrical.... dj
Slow cranking makes me thing you don't have a good ground connection and you are trying to carry current through you linkage. Check the connection by reading from the battery ground post to the block, should read almost zero. Spark plug going to ground won't arc somewhere else.
appreciate it. ill try throwing some plug wires on tomorrow and see how that goes as it seems to be the general consensus.. ive got all the fuel disconnected and away from the vehicle for obvious safety reasons. ill check back in with the results
I assume that this is happening when just cranking over and not running if you have no fuel present. If it is arcing, and not snapping a long single spark you might have a bare wire on the the gas pedal linkage under the dash that is rubbing when moved, and it is grounding back through the carb.
ahA!.. changed the spark plug wires, not that it was a bad idea to say the least, didnt solve my problem. you know that one elusive wire that you don't notice tucked away under the dash the first 10 times you've got your head up under there. that was my big problem.. still doesnt start, but at least i'm back to making progress. appreciate all the good ideas, this time it was just somethingtucked away i didnt see
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