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454 timeing question

C

carver boy

New member
Thans for your help,I have a 1986 Carver with twin 454 crusader engines,I replaced port engine this weekend.There was much talk about LH engine RH rotation engines So on my engine it is a standard rotation. I was told both engines turn same durrection and that the transmission changes the props. Hopefully that is true? My question is the intake manifords on both engines have the timing seq. on them.Both in the book it shows that ea engine is timed differently. And the old distriber and wires are different and it all so looks like on my starboard engine the sea cock water inlet his hooked up backwards then port engine. Please help me out.
 
The answer depends on your exact transmission. You need to know the manufacturer, and gear ratio, OR the full model number. Most, but not all twin 454's of that vintage rotate in opposite directions in twin engine boats.
 
I am not near the boat today, But I know that on the transmission there are arrows that show that the trans turns different from one another Thanks
 
Newer trannies reverse the prop direction internally, eliminating the hassle of reverse rotating motors.

Jeff
 
I would have preferred this on our engines also...When I did a damper plate last year and changed the starter, that RH / LH cost me 2 starters and a few hours wondering why it wouldn't start !
 
The engines should be timed to the same value of advance. What is different is the relative locations of the timing marks on engines with opposite rotations.

I'd suggest getting the info off the ID plate on the gears and engines. Nothing worse than a new install done wrong.
 
It sounds like you have opposite rotating engines. The port should be the CCW so you're OK anyway. They use the same intake manifold and the firing order cast into the manifold is for CCW engines. All manifolds have this firing order cast into them, disregard it for CW engines.

Mark is correct on the timing only the CCW engine will read below or after the TDC mark and the CW engine will read above or before the TDC mark.
 
Do they use the same distributors? When ordering EST full kits (coil, distributor, etc.) they only specifried that RH Vortec engines wouldn't work.
 
Both normally configured rotation Mark IV BBCs take the same distributor. The cam's drive gear is the deciding factor.
 
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