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Old 01-08-2021, 05:03 PM
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C&C32 C&C32 is offline
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2 motors so differnt?

Been working on my A4 on the boat. Its a newer model then the one in my garage. And noticed the valve lifters sit so different in the seats.
Is this normal?
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Old 01-08-2021, 05:05 PM
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Top Picture is the older motor, bottom the one in boat. As you can see the lifters sit quite a bit higher and the old motor sit flush with block. ?
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Old 01-08-2021, 10:51 PM
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sastanley sastanley is offline
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Hello there..I have had my head in the valve train, but I don't know the answer to your question.
However, since you on that side of the engine..between the flywheel and the valve opening there should be an embossed 6 digit date...i.e. 041976,, which is the date the block was cast on my '77 boat. Ignore the more prominent embossing number directly inboard of the flame arrestor...I am not sure what that is but maybe the mold for the is usually 288xxx or something.

Folks that know more than me may know some details based on the age of the engine.
"Twice Around" - '77 Catalina 30, #511 with original A-4 & MMI manifold.
She is even happier with fresh paint on the topsides!

Last edited by sastanley; 01-08-2021 at 10:54 PM.
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Old 01-09-2021, 11:36 AM
Dave Neptune Dave Neptune is offline
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Could just be a casting difference, no biggie~~seen lots of those. Could be longer lifters so they sit higher for easier adjustment~~no biggie. Could also be a "reground cam" which would drop the lifters deeper into the bores for the smaller diameter cam~~again no biggie. I have played with "cam base diameters" when stroking many "V" style motors. The reduction was needed to clear the main journal throughs and rod connections because the now larger diameter would hit the "std" cam causing nasty failures.

My guess is it is just a different casting when the basic block was "changed". We know of many changes and some are even interchangeable and/or adaptable.

Dave Neptune
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Old 01-09-2021, 11:59 AM
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Great input, Thanks.
One on the boat is a 80's A4 the one in garage is 1974.
I realized the difference when I had practised adjusting the clearance on the one on the work bench. Once I went to the boat and using the same tools realized they didn't fit the same. The thick wrenches I was using on the old engine didn't fit on the new one very well. So sourced some thinner ones so I could see what I was doing.

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