Compression #'s = non running motor?

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valves were way out of whack, readjusted per the fsm and it turns over nicely now, have spark at plugs but still won't fire, neighbor helping and mentioned it is probably flooded, makes sense as I have been cranking it for a few days now. I pulled the plugs and shot air in the cylinders and carb to air it out.

also did a 2nd compression tests, #'s a bit better.

Will let it sit and try to fire it in a bit. I plan to also pull the choke valve during starting as well. Wish me luck.

Noah
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ok, dug into it some more today and it seems that the 2f used dizzy shaft is very worn. I did not notice this before. I compared it to the 1f dizzy I have and the 2f shaft where the points ride against is rounded fairly badly. The shaft also has quite a bit of play in it. So we removed the 2f dizzy and cleaned up and installed the 1f distributor, cleaned the ignition points on the cap / rotor, etc.

Just to make sure I: set the BB to the pointer, took the valve cover off and made sure that the first 2 valves have some play in them, pulled #1 spark plug and tapped the piston with a screwdriver AND dropped the dizzy in with the rotor pointing at #4 per the FSM. I also at this time adjusted the valves per the fsm just to make sure. I also reset the points gap on the 1f distributor when the points were on the higher ridge of the shaft.

No fire. I think the culprit is a weak spark. I am getting 12v to the + side of the coil before cranking. During cranking however with a meter at the pos and neg side of the coil the voltage drops to 6v??

We also did a standard spark test using a screwdriver on the valve cover and the spark was very weak.

Remember I am only using a coil, no igniter. The 1f dizzy has the condensor, etc.

So, the question is why would my voltage go DOWN to 6v from 12v at the coil while cranking? The battery is low, but I can't imagine that could be it?

Any comments, suggestions appreciated! I am at a loss. I do have a pertronix unit on order with one of their flamethrower coils along with a trollhole carb. Maybe these will remedy the weak spark but I sure would like to get the truck on the road this weekend.

Noah
 
so I double checked my grounds, made sure the disty is bolted down to the block, have cleaned ground wires. Have neg to starter mount bolt ground wire, starter to frame and then added another ground cable from neg batt cable to alternator engine block. Still won't start and still getting only 6v when cranking the engine with the meter probes at + and - of coil. Any ideas??

Noah
 
Hey Pinhead, yeah have had the disty out probably 100 times by now. Talked to my father in law whom used to build engines and he thinks I am 180 out as well. I plan to check spark at the plug to see if it is yellow or blue (hot). My father in law also mentioned that it is somewhat normal to only have 6v. I have a trollhole carb on hand I think I might slap on there as well.

He told me to turn the crank until the bb is pointed at the pointer and the back of the rotor is pointed at 1 cylinder on the cap, THEN pull the disty and rotate 180 and drop back in. Hopefully that will do the trick.

this engine should fire....

Noah
 
Turn the engine CW and watch the intake valve for #1 close and then bring it up to TDC for #1.
If it is 180 out, just swap opposite wires at the distributor cap.
Being 180 out could explain why your valves were way out, depending on how you set them.
The stock points distributor does not need an ignitor, but the Pertronix does.
 
1973Guppie said:
I believe the ignitor is included in the unit within the distributor, thx......
Click to expand...

Yes, it is. I've had a Pertronix in use for several years now.

Don
 
1973Guppie said:
Hey Pinhead, yeah have had the disty out probably 100 times by now. Talked to my father in law whom used to build engines and he thinks I am 180 out as well. I plan to check spark at the plug to see if it is yellow or blue (hot). My father in law also mentioned that it is somewhat normal to only have 6v. I have a trollhole carb on hand I think I might slap on there as well.

He told me to turn the crank until the bb is pointed at the pointer and the back of the rotor is pointed at 1 cylinder on the cap, THEN pull the disty and rotate 180 and drop back in. Hopefully that will do the trick.

this engine should fire....

Noah
Click to expand...
IIRC, the starter /ballast resistor that is the long ceramic thingy on the side of the older dizzies, is disigned to give you 12v for starting, but then switch it down to 6v for normal running, so as not to burn up the points. Sounds like yours is working the other way around.....................
 
new trollhole carb installed, engine cranks well, plenty of spark (blue and shocked me) out of the plugs, the car seems like it wants to fire but instead just puffs white smoke out of the top of the carb and one open port on the intake. any ideas?

seems like timing is off but I have gone over and over on this and still no luck. This morning I turned the bb to the pointer when the backside of the rotor pointed to #4, pulled the disty and reinstalled with the rotor pointed at #4. Still no luck.

plugs are darkened with lots of fuel.


Noah

Noah
 
Leave the dizzy in a little loose and try to adjust the timing while cranking it over. It sounds like your timing is still off and you may find the spot while turning the dissy. Are you sure you're still not 180 degrees off?
 
this morning was thinking I was 180 off, but I came out and turned the flywheel to the bb / point mark where the backside of the rotor was pointing to #4 spark plug, pulled the disty and dropped it back in with the rotor pointed to 4 and still nothing. I am at a loss right now.

Noah
 
ok, have been doing some reading and using the search button

question: I have been using the bb lined up with the pointer, I read that I should be using the "tdc line" on the flywheel, is this correct?

question: when determining tdc, someone mentioned that a good way to do it, is to watch the #1 piston and put your thumb on the hole and you should get pressure on the #1 pistion. You want to set tdc when the pistion is coming up, ie: compression, correct?

Noah
 
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