Chrysler 85 hp. 1970 or so?

[amuller]

I had occasion to look over one of these this afternoon. Overall it seems a simple and straightforward 3 cylinder design. Does anybody know why they chose to use a belt driven distributor ignition setup? I thought of the West Bend 80 hp four, which used a separate coil and point set for each cylinder. About as simple as can be. Why didn’t Chrysler stick with something like that? Nothing against the distributor, but it seems to add cost and complexity. Probably I’m missing something.

Also, my experience is mostly with small and simple outboards. It seems that with a carb for each cylinder, if one goes lean for whatever reason, that cylinder is likely to be cooked before the problem is noticed. Or is there some protective function at work?

Thanks.

[frankr]

Totally unfamiliar with that motor, but the carb for each cylinder is much more efficient and one of the main reason they get a lot of horses out of small size and weight. The practice is very common. "Old" technology with one carb feeding more than one cylinder requires a large crankcase and the incoming fuel has to go around corners and past dead spaces. That causes the fuel droplets to rain out of the mixture and settle at the bottom (did I hear "gas hog" and crankcase drain valves?) Separate carbs and straight-in charge flow fixed that. No, there was no protective device as you suggested. At least not back then.

BTW, the Dark Side discovered the compact crankcase design way back when. That’s one reason they kept outrunning the competition.

[frankr]

1969 Ad. Separate carburetors for each cylinder and straight-in induction was the major factor in getting more power out of same or smaller size. In fact that was the difference between the 75hp and 90hp.

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[amuller]

I see the point of individual carbs from a performance point of view. No question about that. Hadn’t thought about the advantages in reducing crankcase drainage; that makes good sense. Am not sure whether Chryslers have more than their share of bad cylinders, or why.

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