I helped a friend pull his motor to check a knock and after having the rods refitted and reinstalling the motor in the car it refuses to start. I went to give him a hand trying to get it going and found that it is popping back through the carburetor. With all the plugs out and laying on the head they fire in the proper order just after TDC on the compression stroke. A compression test shows good compression on all four cylinders so I assume the valves are closing fully. I swapped the carburetor for one from a running car with no change. The car has a two piece timer and the fellow who worked on the rods swears that he did not touch the cam although my initial thought was that the cam had been removed and replaced incorrectly. I have tired everything that I can think of without any luck. The car was running fine before it developed a knock.
Has to be a timing issue Might check the pin that holds the rotor or brush Make sure it hasn't been damaged or bent I don't think you can put the roller or brush in 180 degrees out that at least seems Murphy proof
If the pin hole in the camshaft goes completely through you can be 180 out of time!!!!
As stated, I would be checking the ignition timing as well.
I sit corrected! I haven't seen one that went through the camshaft before...Murphy strikes again
Did you also try enrichening the mixture 1/8 of a turn?
The cam position is easy to check.
Take off the valve cover plate and turn the engine so the starter pin in the front pulley is horizontal, even with the underside of the motor block and the pistons 1 and 4 are all the way up. Now 1 and 4 cylinder will (should) be in TDC. To see which is on compression, just take a 0.10mm valve gauge and try pass between the valves and the tappets. The cylinder who the gauge pass is the one on compression the other is at the end of exhaust.
Now it is time to check the ignition wiring (I think your problem is there).
With a test light between the battery and the wire terminal of the cylinder on compression (1 or 4) on the timer, the lamp should light up or you should be able to make it light up by turning the timer a few mm left or right. If you have no light just look for the terminal that does light up. this will be your staring point to connect the ignition wiring. Firing order is 1243 and the timer is turning anti-clockwise.
Hope this helps.
Agreed the first thing to check is the timer register.
I lost 2/3 of a day one time because I put a new Anderson style timer on by feel in a 27...wouldn't start...tried everything even scratching my head...then pulled plugs and laid against the block...when the piston was just past TDC on #1...it wasn't plug #1 that was firing!
Had that 'well I'll be' moment when I found the camshaft had been drilled through at some point in its past and I had put the flapper on 180 degrees out.
George the hole goes all the way through on the cam and my friend had the roller 180 degrees out initially when he called me over for help. I corrected that and confirmed it was correct by watching the plugs fire in the correct sequence on the compression stroke of the correct cylinder. Unfortunately, the car still won't start.
Andre, I will check the valve timing as you suggest. However, I don't think it is the wires. Holding my thumb over each cylinder and watching the plugs fire the firing sequence is correct. That's what has me stumped. This is an open valve engine with a two piece timer and I am inclined to think that the problem may be in the timer if the valve timing is OK.
I will try to get back down to my friends later this week and hopefully figure it out but in the meanwhile any other suggestions would be greatly appreciated.
OK, step #1 out of the way...no need to worry about any other cylinder yet, double check #1...spark all the way up and even taped...thumb over spark hole #1 on full up until it blows your thumb off...watch/angle screwdriver while you turn further slowly until the screwdriver/piston top just starts to lower...watch the spark plug for #1 as you turn on 'batt' and rotate timer until you hear a buzz or see the arc...back it off until no buzz. Button it all up and follow wiring diagram from there. That way you know for sure it is correct from that point. You probably did this several times already...but just mentioning it again.
Do the plugs get wet? Doesn't take much of a manifold leak to kill the suck needed to draw real fuel as opposed to sounding as though it is trying...
Is there fuel in the bowl? Always worth a check and if it were me I'd choke and pull thru until it was spilling out and wait for it to settle...AND...open the needle valve a bit. Too lean, never start, too rich always still starts and you can adjust from there...
You might want to check the spark throw. Just because they jump in air doesn't mean it will jump under compression. Get it to jump about 1/4" in air and she'll be fine under compression. Some guys say whoa about this step as it supposedly can screw up a coil, but when all else fails...and only do it for a second or so at a time.
Fuel...Compression...Ignition...Timing both mechanical and electrical ...that's all it ever is. Has to be one of them.
Process of elimination gets you down to cam in wrong place, but that too is check-able as described above.
My gut tells me since still a total mystery manifold leak along about now if all else is as you say. Copper crush rings? If so, he didn't reuse them did he? That is false economy to do so, crush 'em once, use 'em once. Along about now is where a set of 3 in 1 greenies go just to prove or disprove a point! I did that with one car for a guy and he actually liked the greenies...so I slid the glands in to hold the manifold in place and left him green
Just forget to tell you:
- The distance of the rod connection center on the timer to the bolt center that hold the spring should be 2.1/2 inch. Than ignition is set a few ° after TDC.
- The firing order could be correct but the wires could be set off 90°. Than you will fire at the end of the intake stroke.
Glad to see that your " friend" wants to get his car ready for Boone. You can always ask Dave to stop by for help. Darn Fords!
Hey Willard. My friend won't be going to Boone as he will be in Germany by then. I just want to figure out what the problem is before he leaves otherwise it will bug me all summer! It is not my car that is having the problem although they are both '10s. Speaking of problems, I think #3 on your '12 is giving Dave a fit!
Andre, thanks for the advice but I would be careful using the distance method for setting the timer. It does not work on the early cars. I have his car set so that the plugs fire at 15 degrees after TDC with the spark lever in the full up position.