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Confused with starting/ignition/timing

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10musketeer

10musketeer

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O.K. guys and gals, I'll admit I need your help.

After trying to be proactive, and solve a tough starting problem, I attempted to change the points and condenser on the distributer. When I got in there, I noticed the points stuck on due to a stripped screw. They look new, and the gap was good, so I opted to leave them. I changed the condenser since I was there. I did all this without removing the distributer.

When I tried to start the car, it backfired and would not start, so I thought the dizzy must have turned some. I tried having my wife crank the engine over while I rotated the dizzy slightly, I went back to the old condenser, and static timed by putting the car at TDC, rotor to #1, rotated the dizzy left until test light goes out, and then back to the right (clockwise) until the light comes back on.

After all this, all I get when the engine cranks over is backfires through the exhaust and every once in a while a bang through the carb (weber).

Any ideas? I'm totally confused as to why the car ran ok before and now won't start at all. I'm getting bangs, so I would guess I have spark. What do you think I missed?
 
I'm thinkin' the plug wires are out of order. 1-3-4-2 counter clockwise with 1 ar about 2 o'clock... 3 at 10, 4 at 7 and 2 at 4 oclock.....

All times are CDT ;-)


Peter
 
Both spark AND fuel if it BANGS. Another ~possible~ answer is: the dizzy drive dog is in 180 out from correct. When the timing mark is on TDC, and the #1 rockers are both 'loose' is the rotor in the "2 o'clock" position? A "quick-n-dirty" test would be to just put what WOULD be #4 wire on #1 plug, then go counter-clockwise with 3-4-2... Crank it and if it starts, the drive gear is "upside-down"... not an uncommon mistake.


This'd be EDT! /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
I think I have 1-3-4-2 in the correct spots going counter-clockwise, and I don't think the drive gear is upside down, but only because I didn't remove the dizzy. All I did was take the cap off, replace with a new one, remove and replace the condenser and put the cap back on. Now just bang, backfires and pops through the carb. /bcforum/images/%%GRAEMLIN_URL%%/frown.gif
 
So you are certain #1 has always been the 2 o'clock wire...

I'm out of ideas then.

BTW: the dizzy can't be inserted "wrong" in the drive gear, removed or not. It's the last engine builder I'm musing about. Your static timing method is spot-on, if the firing order is correct and you're getting 'reports' without start, the 180* out drive gear is the ONLY other thing to cause it. Swap the wires to have #4 as the #1 plug, go thru the order and spin it... all it can do is BANG some more.
 
Hmm, good to know, I'll try it! I never thought of leaving it 180 out by changing the wires. I'll let you know!
 
I'll sit here and wait...
 
Sorry it took a bit to get back to you guys.

I was excited to hear it roar, so I put...

4 in the 1 hole, (2 o clock) then
2 @ 11 o'clock
1 @ 7 o'clock
3 @ 5 o'clock

All I got was a very labored turnover and pops and smoke out of the carb.

Did I do this right?
 
If the points hold down screw is stripped, are you sure the points aren't moving around? Try using a dwell meter and see if you get a steady reading, or if it flies all over the place.
Jeff
 
OK, I asked a question about static timing a couple days ago and was unsuccessful. In your original post you seem to have covered 95% of the information I need as well. I nearly got it all, but you mention a light that goes out and then comes on. Where is this light wired, and what kind of light is it?

In my case ncbugeye runs, and is still wonderful fun to drive, but she seems to have the performance of a worn out 803cc engine rather than a 1275, is smooth at idle and at steady speed, but misses badly going up though the middle of the rev range, and the exhaust pops when I lift the throttle.

A week or so ago I read Jack Laird mentioning something like "should be smooth as silk" and wonder how to get there.
 
The points seem to be tight (in fact so tight I can't get it off) Can I use a dwell meter when just turning the engine over? I tried a while back and got something like 60, which I know can't be right. I used a feeler gauge and it was right at .004.
 
I would think that .004" would be kinda tight for the points. Not sure what a 71 should be but I'm more used to something between 10 to 15 thousands. What you are describing sounds like it is 180 degrees out now. Your initial description sounds like late timing but I can't be sure. You will need to test the strength of the spark. Open an old plug up quite a bit and make sure that you ground it to the block. Have someone turn the engine over and look at the spark. It should be fat and blue. Also check the plug and coil wire to make sure that they are making good connection. Particularly the coil wire as it would affect all cylinders. If the spark is having to arc before it reaches the plug it will loose a lot of energy. When you get the timing close it should fire but may not run great. You can dial it in from there. Don't give up on it. It is something small and you will find it.
JC
 
60 is correct on the dwell, but the feeler gauge should be between .014~.016.
Sure, you can use the dwell meter just cranking the engine over. Pull the plugs out to make it a bit easier on the starter.
Jeff
 
10musketeer said:
Sorry it took a bit to get back to you guys.

I was excited to hear it roar, so I put...

4 in the 1 hole, (2 o clock) then
2 @ 11 o'clock
1 @ 7 o'clock
3 @ 5 o'clock

All I got was a very labored turnover and pops and smoke out of the carb.

Did I do this right?
Click to expand...

*GROAN*

.015" points gap.... a matchbook cover is as good as anything for this.

Set static timing with a light as you did the first time.

Okay, okay... Use the dizzy cap position for #4 ((7 o'clock)) as the #1 plug wire-to-#1 plug... then in a counter-clockwise direction connect #3 plug (5 O'clock), #4 plug (2 O'clock) and then #2 (11 O'clock).

Start the car.
 
Hmm. well that sounds like what I did. I must have some other problem. I'll try trouble shooting something else for a while.
 
"should be smooth as silk" and I stand by that. Just sounds like maybe you have a bit of a timeing problem Chris, have you checked it with a light?
 
I would initally suspect a points/condenser problem since it began with fiddling with them, especially if you have some kind of questionable hold-down screw. Below the points plate are the counterweights, check if the little return springs are still in place, if not that could cause problems similar to what you describe as well due to erratic spark advance!
 
Maybe I should take the dizzy off and give it a good going over. Sounds like I may have a more potentially annoying, if not serious problem with the distributer. i checked it with a timing light a while back and noticed the mark jumping around, which at first I suspected was a cheap timing light, but it may in fact been an indication of a worn dizzy. There seems to be little play and everything looks good, but somethings causing a problem. I'll get it!
 
Describe that stripped out screw again!...jumpy timing could be there in the dizzy or maybe even a problem with wear in the timing chain assy. A worn dizzy would exhibit some play. Also check a sticky vacuum mechanism!

Your points should be gapped at .014 to .016 in. (0.35 - 0.40 mm). Itsounds like you may hve the points virtually closed at .004 as you mentioned above!
 
The screw just has a worn slot in the top where someone has rounded the groove and I can't get a screwdriver to grab enough to break it free. It seems that it has good threads, but was just tightened a little too aggressively in the past by the P.O., then the slot damaged as he tried to remove it. Everything inside looks nice. Springs are there and work, vacuum advance works when hooked up to a vacuum pump, all parts look clean.

Everything was fine but I had a little timing issue, and so I retimed it with a light, and noticed the light jumping a little. I then checked with a dwell meter and saw 60 degrees. I knew this was wrong and figured I would look into the dizzy. While looking at it, everything looked good and seemed to work inside, and I thought I would replace the cap, points and condenser while I was there. After noticing the points looked good (gauged at .014, sorry for the incorrect number in the previous post) and having trouble with the screw I left them alone and put things back together. Then wouldn't start and would only bang. Thought maybe the dizzy had been turned, so tried to re-time slightly knowing I couldn't be far off since I didn't remove the dizzy. After many tries, I started over with a static timing and still am getting the same results- backfires through the exhaust and pops through the carb.

Hope this can help someone guess what's happening, and I'm sorry if it's confusing, but I'm stumped.
 
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