eab flathead engine starting

5

52fordv8

Member
ok heres where im at all new plugs and wires and cap and condensor new coil new points points set is inbetween 0.14- 0.16 like i have read about and u pour little gas doen the carb and it hits and like it back fires threw the exhaust u can feel the heat where it burnt up the raw gas . and the exhaust pipes steam . could this thing have a stuck valve in it ??? causing that or maybe a stuck ring ??? cause its not back firing threw the carb as it should if it was out of time or etc . i rechecked the firing order made sure that no wires was crossed and etc . or maybe the carb aint doing its job ???
 
no havent had the heads off yet . im getting to tat point where i think im going to pull the heads and intake off and sprin it around and see whats going on in the cylinders and see if all the valves are moving and etc . besides its just costs a set of head gaskets and intake gaskets to see whats going on in there i guess
 
in my very limited experience, checking engine vacuum against one of the charts can tell you what is wrong. a compression test can tell you where it is wrong. I wouldn't pull anything first. I was asking about heads to guess the state of the gasket. Good luck.

Bill
 
so i have a compression tester so i need to pull one plug at a time and screw that thing in and turn the engine with the battery and see what each cylinder psi is
 
sounds like a stuck exhaust valve, run a compression check to find the bad cylinder, pour some marvel mistery oil in the cylinder and let set for a day or so, then turn engine over to distribute the oil and clean out the cylinders, this works most of the time
 
remove all plugs when doing a compression check, you can put your thumb over the spark plug hole and turn engine over, you can usually feel the difference in compression on weak cylinders, a short cut, but its still better to run a full check
 
ok ill try that . i know when i take each plug out u can look in the hole and see a valve open up to the top on each cylinder ???
 
yes but you cant tell if it closes all the way, and a little more info, if you have a stuck intake valve the engine will fire out the carb, just like an ignition problem
 
yes thats just a quick way to find a weak cylinder, but that quick test doesnt take the place of a complete engine compression test, also tie the carb wide open before you check compression
 
ok ill do that tomorow ill take all the plugs out and etc and do 8 fast spins and just see whats going on i have a tester what psi is ok on the gauge ???
 
Probly a valve stuck. Pour the MMO down the carb going side to side so it goes to each cyl. bank. Turn engine while pouring.
 
Block your throttle plate(s) wide open when doing a compression test.

Like someone else said, pull all your plugs (you're going to have to pull them all anyhow) to get the highest cranking speed you can.

BTW - We have seen engines pass both compression and leak-down tests and still have intake valves stick once the engine came up to temp.

Don't know if it will work as well on a flathead since the valves are upside down, but I have seen Seafoam work miracles. Fixed both sticking valves and stuck rings bringing compression back into spec. Never believed much in magic additives until now. I'm now a Seafoam acolyte.

We also had some engines with little petcocks in the intake manifolds to spray Marvel Mystery Oil (what you call MMO?), or Kroil. Shoots it right at the intake valve. It was SOP to routinely give it a few squirts.
 
You must log in or register to reply here.
Back
Top