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Discussion Starter · #1 ·
Background

After having my 69 CL350 sit for a couple months due to a full carb rebuild where I got the float height too high causing carb flooding, I finally got it back on the road and it was running great with new battery and properly set up carbs! Note that I did not touch the timing, points, or cam chain tensioner this time around (ain't broke don't fix!) So she's purring like a kitchen, cruising down the highway at 70 and suddenly starts behaving as if low on fuel and eventually dies and will not start back up. Pulled the points cover on the side of the road, discovered the right point was out of spec and not sparking, got it within spec, still no start. Had to take the bus home... Figured the timing got borked and came back next day with my dynamic timing light (2 leads, an inductive plug wire clip, and a single button). I've only set timing dynamically with engine running before so I attempted to do that same thing, and just set it dynamically with the crank of the starter motor. To my horror, it was about as in-between timing marks as it could be (like where it says 286, halfway between F and LT), and I could not get it even close by moving the plate as far as it would go in either direction. Had to borrow a buddy's truck to go get it, now it's sitting in the driveway while I scratch my head.

Questions

1. Is there anything wrong with using the dynamic timing method on a non-running motor as it spins under the power of the starter?
2. Alternatively, how would one hook up the sort of timing light I have (black and red leads, plus an inductive plug wire clip) for static use?
3. As I was dinking with it, I stupidly messed with that central outer bolt, and the head just twisted right off like butter. To my understanding, that just holds the advance unit in, and once the points plate is set over it the plate holds the unit in and the bolt does nothing, correct? Or does the bolt serve a critical function and need to be tapped and replaced?
4. Here's the thing I'm afraid of... the timing appearing to be off by that much sure seems to smell like a skipped cam chain tooth. I have not yet pulled the points and advancer to check, but does this sound like a good bet, considering the last time I tensioned the cam chain (to the best of my admittedly narrow ability) was about a thousand miles prior? If this is the case, what are the odds I have bent valves or other serious damage?
5. What would be your order of next diagnostic steps?
 

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That bolt holds the slip-over points cam on the end of the camshaft. The points cam is keyed, but can go on in two different positions, one of which is 180 degrees out of time. It's possible that the points cam has spun for some reason, either from the broken bolt or a sheared key. Slide it off and take a look at it (but mark it first so you can put it back on correctly if that's not the problem.
 

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Discussion Starter · #3 ·
Thanks. If it turns out that it's in the right position, it should be fine to leave as is, correct? And does the rest of my thinking / timing process check out?
 

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You need to pull the valve cover and check where the timing mark is on the cam sprocket in relation to where the ignition timing is with your points. As the poster above noted the advancer can be 180 degrees out. If you didn't remove it at anytime then not likely your problem.

That's why I am suggesting removing the valve cover to see if the cam chain or something else has moved/broken. Hopefully you have a shop manual to assist you in looking for the correct timing marks on the cam gear. It could also be something entirely different causing your issue, yet timing is a good place to start looking.

I am not a 350 guy but a Honda guy and there will be markings on the cam gear assy that the shop manual will be needed to tell you if something has shifted. You can only be out 1-2 teeth on most motors before you get into pistons greeting the valves. If you had that happen then the motor would be locked up from serious internal damage.

Oh and you need to repair that broken bolt that holds the advancer it has the bolt there for a critical reason. It is into the end of the cam so be careful in removing it. A reverse drill bit will likely back it out fairly easily. I have also never seen anyone set dynamic timing other than with an engine running and likely why you got the weird timing reading.
 
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