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Hi all,

I have recently had my generator rebuilt and after I installed it I noticed that the car just didn't run right. It lacks power and I hear under the right conditions (low rpm in 3rd gear) popping noises almost like a backfire but it was popping through the carb. I never looked inside the front of the engine but I assume there's a chain that wraps around the gear that drives the generator and it's the same chain that maintains the timing between the cam and crank. My fear is that I've somehow messed up that alignment and have to take the front cover off the engine which probably requires me to remove the hood and radiator which is no easy task. If I didn't lean on the generator enough to tighten the chain properly, could that have caused the chain to skip on the gear(s) and misalign?

I live in FL and it has been extremely hot the last couple of days when I took the car out so there might be some other explanations but it just seems to me like this is the most plausible given that the car was fine before I messed with the generator.

I also thought perhaps I cracked the distributor cap with all this heat. I haven't looked at it yet because my mind is so focused on that timing chain. I did have a Mini Cooper once and rainwater hit the distributor cap and cracked it with similar results on engine performance.

Any thoughts would be greatly appreciated.

Thank you in advance,
Crin

After reinstalling the generator, did you check and adjust if necessary the timing chain free play before restarting the engine?

At first I put a pry bar on the generator and tightened it. When I started the car it made a sound like the bearings were over tightened so I loosened it and I'm afraid I ran the car with the chain too loose.

I don't know how to check nor adjust the timing chain freeplay. I'm taking the cover off today so any help would be greatly appreciated. Thanks [PROCESSING IMAGE.... PLEASE WAIT]

You check the timing chain tension via the round inspection port on the timing chain cover.

You adjust the chain free play via swiveling the generator around its pivot.

Oh great. How do I know when it has the proper tension? Thank you

I don't recall ever seeing a factory specification, it may be in the factory blueprint on engine assembly notes, I'll take a look later and see. That not withstanding, if memory serves, folks who service these motors generally seem to recommend about 1/2" max deflection at the inspection port.

PS. Per note 7 on Packard factory blueprint MISC-1-730 "Motor Construction Notes", maximum total deflection should be 1/4" measured at the midpoint between the generator and the camshaft. This print was published for the 11th series 8-cylinder models and I know of no reason why the 14th should be different.

You are awesome as usual. Thank you so much

I've edited my post since your response, please re-read it.

Thank you for the additional information. I definitely have more slack than that and I will adjust accordingly. I did confirm that it's still timed correctly which is a relief on one hand but now I'm moving on to adjusting the valves which haven't been touched in about 6 years (shame on me). I'm hoping that's why it was popping through the carb.

If anyone knows what the cold gap should be for the valve lash please post it on here. All I can find is the hot gap and I can't even begin to imagine how these poor souls adjusted the valve lash with the engine hot.

Here are some either cool or scary pictures from today's activities...

Thank you for the help.

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Watch Ross's video on the valve adjustments.

youtu.be/L79ntnnzFHk?si=3Pnb7F50Yb3po9Bq