Star Letter - Chrysler problems
Dear Classic American,... I’m writing in regarding the problems your contributor Ed Hall has been having with his Chrysler, I would guess you have almost answered your own question. It’s the timing chain. The easy way to check the valve timing is as follows. Remove both rocker boxes, turn the engine to T.D.C. firing number one.
Use the crank timing marks. Both valves should be closed, at the same time the valves on number six should be rocking, i.e. one should be about to open, the other should be closing. Rocking the crank slightly backwards and forwards will show what I mean. I have said number six but that is only from memory you had better check on that.
The chain has probably stretched and the nylon coating has probably started to break up on the cam sprocket I had a similar problem on an Oldsmobile many years ago. It took me ages to sort it out. Since then I have seen it several times, sometimes on low mileage engines. And they say Morse chains don’t stretch! I hope that solves your problem.
Mel Atkinson is turning into one of the most prolific correspondents to Classic American and we reckon be long ’til he has his own column here! This is what Classic American contributor Ed Hall had to say in response to Mel’s advice: ‘Many thanks for your advice Mel. Having done some investigations on the Chrysler's engine it looks like you’re spot on. A knackered timing chain/sprocket is the cause. There are 5 degrees of play in the crank before the cam/dizzy start to move – I measured this using the TDC marker. I guess 5 degrees at the crank would equal 10 degrees at the dizzy, which explains why I needed an indicated 20 degrees of static advance to get it to run. And with the valve timing so retarded it’s no wonder it runs so badly. You can actually hear the chain take up slack as you swing the crank either way using a breaker bar. Many thanks for this invaluable bit of advice…
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