'58 CJ3B Intermittant Missfire

[GunnersWillys]

On the timing, I hooked up my light and clearly see a mark on the pulley.  There is a "pointing finger", not sure what to call it, that is wide at the top and tapers to a point at the bottom.  At idle the mark is nowhere near that pointer.  And it doesn't really move much when I rev the engine.  Does that point represent TDC?  Or 5 degrees before TDC?  And at what RPM should I lock it down.

Odd, but none of this is in the book I have.  It just discusses static timing.  Thanks.

[Rus Curtis]

Look at 1955CJ-5's post here:
https://cj3apage.com/Forum/index.php?topic=3538.msg29819#msg29819

Is this bolt on timing mark what you're describing?  I would think there should be two marks on it.  Using the image from above, the notch to the left is 5* before and the notch to the right is TDC.

My timing mark is stamped into the timing gear cover and I used a toothpick to dab a little bit of white paint into that mark as well as the pulley notch - makes it easier to see with the timing light.

Added:  Here's an image I used when I discussed my oil hose issues.  You can see the timing marks highlighted with white paint.

[GunnersWillys]

Back at it.  The bolt-on timing mark is what I have.  So the edge closer to 9:00 would be 5 degrees BTC, and the edge closer to 12:00 would be TDC.  Makes sense. 

Do I check timing at idle? Or rev’d?  I did the same as Russ when I rebuilt the engine and put a white mark on the pulley so the pulley notch is easy to see. At idle the mark is an inch away from the BTC mark. It’s a vacuum advance distributor, so I can rev it and it moves toward it.  I can move the distributor enough to get it close, and it runs really rough.  It ran great after I rebuilt the engine.  Since I got it back from the guy I sold it to it has run well a couple of times prior to touching the timing.  So I moved on to fuel.

I drained all the fuel, pumped it out of the tank actually.  Put in 3 gallons of fresh gas.  The old fuel seemed fine, no water.  I pulled the top off the carb.  There is a little bit of trash in the bowl but not much.  With the float pulled out it was just under half full.  I adjusted the float to allow more fuel and reassembled.  No change.  I sprayed carb cleaner down the throat with it running, no change.  I have not pulled the carb and cleaned the main body, but maybe that is next?

Kind of stuck now.  Weird part is after I put in new points and condenser it ran and started perfect, then it degraded again.  Not sure what to try next.  Suggestions? Thanks.

[GunnersWillys]

Update:  This morning I pulled the carb and cleaned it.  There was a little bit of crud on a needle, but not much.  Reassembled, no difference.  Still running really rough.  Fresh gas, clean carb. Still not sure what to do next.  All that's left are spark plug wires and a maybe a new distributor. 

[Rus Curtis]

....none of this is in the book I have.  It just discusses static timing......

At the risk of stating the obvious, have you verified wires are in correct order?  If you put a wrench on the crank nut and slowly turn until you feel compression with your finger in the #1 spark plug hole, pop the cap and see where the rotor is.  Even if it's not at the 5 o'clock position mark it as #1 then: 1-3-4-2 CCW.  (mine was 180* out).

[GunnersWillys]

Thanks Russ, and yes, I've confirmed.  I had to because when I replaced the cap I got the wires mixed up.  That was a couple of weeks ago.  I rechecked just to be certain I didn't mis-wire since then. # 1 is at 5:00 as it should be. I rebuilt the engine a while back and have the oiler positioned properly.

Update:  After more reading I realized I can use my timing light to confirm I'm getting spark to each plug.  At idle its a nice steady flash.  As you raise the engine speed you start to get misses. They show up in the flashing pattern on the light.  The flash stumbles as the engine stumbles.  It is consistent on all four wires.  That tells me the issue is upstream from the plugs and wires. 

I've checked all related wiring looking for a possible break, inside the distributor as well, nothing.  The rotor is the only thing I haven't replaced.  I'll order one on Monday, and new points and condenser just for grins, and see what happens.  If that doesn't fix it, maybe it's time for a distributor?  No telling how old that one is. 

[SteveKfl]

Nice trick to 'see' the spark action on each cylinder with the T-Light.  Have you tried it with the vacuum advance disconnected and line plugged to isolate the distributor timing to watch the spark and running impact?  My thinking is that since you said your timing lights 1" from the pointer (retarded), but you are OK with the wires and positioning of the rotor to #1, is the v-advance mechanism involved?  Now I have to look it up, but I thought I remembered that 2 o'clock was the correct position for #1.  OK, it is the "oiler" that is to be at 2 o'clock, clips at 3 & 9.  Also, I'm wondering if that rotor may be worn, or the cap contacts, and at speed can't jump the gap is another culprit I'm guessing about.  At least "fuel" is not on the list now.  Keep us learning along with you.  Thanks. 

[scoutpilot]

Your misfire gets worse with increased rpm? It happens at all four cylinders? Commonality? Points. The new set of points. Does it have a chrome steel helper spring that rides next to the copper strap? If not, your points are floating and unable to make good steady contact. OR. Check the distributor shaft for play, side to side, 3 to 9 and 6 to 12 o'clock. A worn bushing in the distributor body will cause the same problem.

[Rus Curtis]

Next I installed new points.  Now it won't start at all, even with ether.
I noticed the distributor cam has a lot of play.  Pulling on it you can move it up maybe 1/8th of an inch.  No movement side to side, but spinning it clockwise or counter/clockwise, it moves more than I expected.  Issue there?

Same for me.  I had a garage work over my jeep way back.  They idled it but didn't do a "tune up"  I drove home but could only hold a very rough 20 mph.  I ended up just towing it the rest of the way.  Later, it was pointed out by another mechanic (as Scoutpilot mentioned) that the distributor shaft had too much play - this affected the points opening and closing.  I didn't know anything about rebuilding, so I replaced the whole distributor and got it to run as now the gap on the points would stay where it was supposed to be.  Then, I didn't have a dwell meter nor a timing light.

If there's a fluctuation on the points, you should be able to measure this.  I also thought of the "spring" that's included with some brands of the points set.  The copper strap is only for electrical connection, the spring is also needed.

[GunnersWillys]

Thanks for the distributor comments. I don't have any side to side movement, 3:00 to 9:00 or 12:00 to 6:00.  It will pull in and out a bit, and spin a bit.  I'll double check later today.

I ordered a new ignition rotor from my local FLAPS and it is due to arrive in a couple of hours.  I'll report after.  Fingers crossed!

[GunnersWillys]

Well, no change.  New rotor, same issue.  Russ, the spring is on the points as required, so that is not it.

I can spin the distributor far enough now that I can line up my white mark with 5 deg BTC using the timing light.  Runs even worse then.

I'll order new points and condenser from Walcks tomorrow as what I've bought from them before worked well.  If that doesn't fix it, new distributor I guess.

EDIT:  In doing some extra reading I realized the coil I picked up from my local shop does not have a resistor built in.  I swapped back in my old one, which tested out fine with a meter, and some improvement.  I was able to set the timing where it should be and it starts quickly and accelerates smoothly up about 2/3rds of the way through, then starts to spit.  Still won't wind out without serious spitting at the top of the rpms.  Making progress though!

[SteveKfl]

Before buying a new distributor, have you considered trying moving the plug wire locations one hole and try timing it again?  Just 'wondering' out loud.  Good Luck! 

[GunnersWillys]

SteveKFL:

I considered that.  I rebuilt the engine myself a while back then sold it, so I know clocking was perfect "before" I sold it.  No telling what the interim owner did while it was away.  See above, just got the timing figured out, I think. 

[Rus Curtis]

EDIT:  In doing some extra reading I realized the coil I picked up from my local shop does not have a resistor built in.  I swapped back in my old one, which tested out fine with a meter, and some improvement.  I was able to set the timing where it should be and it starts quickly and accelerates smoothly up about 2/3rds of the way through, then starts to spit.  Still won't wind out without serious spitting at the top of the rpms.  Making progress though!

Well now.  I used an inline resistor at first when I switched from 6V to 12V.  This time around I ordered a coil with an internal resistor.  It may be cheaper, easier and quicker to get one of those resistors and add it to the new coil. 

[GunnersWillys]

Okay, back from a work trip, new points and condenser arrived.  Before installing those I made a new jumper from the coil to the points thinking maybe one of the wires was bad.  Direct instead of using the terminal block, ran it through the terminal block hole.  No change.

Installed the condenser, no change.

Installed the new points, it actually ran a little better but not fixed.  Then idling in the garage it slowed down and died. I checked the gap, it had closed some.  Tried resetting it and ran into what may be another clue.  I cannot get the points to open quite to the suggested .020" gap.  Fiddling with the adjustment screw, it just won't do it.  It's like the thing (not sure what you call it) on the points that makes contact with the cam is too short.  Problem is, it is that way on all the points I've tried.  I do have grease on the cam.  So is the thing on the points wearing down immediately?  Or, is the cam in the distributor worn to the point where it will no longer open the points? 

If so, back to the new distributor plan.  Walcks has them, but only in mechanical advance.  Kaiser Willys I think has vacuum advance, but I have to supply the vacuum unit.  Thoughts?