twin 350`s

scarabite

Cadet
Joined
Jun 3, 2014
Messages
15
Just bought this boat about a month ago 1983 scarab 11 26 feet twin 350`s alpha gen 1 drives. This is my fourth boat first twin engine. Both engines are standard rotation my question is when i get up to cruise or wot my port engine seems to reach significantly higher rpm then starboard. So i have to back off on the port engine to sync them.Depending how many people i have on board wot seems to be anywhere from 4000 to 4800 is this normal for twins?
 

wrench 3

Commander
Joined
Aug 12, 2012
Messages
2,108
Your engines should run out between 4400 and 4800 RPM at wide open throttle. Twins usually run at close to the same RPM. Alphas have a standard rotating engine and use a counter rotating drive on the port engine. If you have a standard drive on both sides maybe someone replaced the port drive with the wrong ratio. Also, are both props the same pitch?

BTW, welcome to iboats. I hope you hang around to see how great it is when they get the bugs out.
 
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scarabite

Cadet
Joined
Jun 3, 2014
Messages
15
Yes im running both drives aluminum 21 p 3 blades, i had a previous account on iboats about 4 years ago, kind of got lucky with minor issues untill i traded up to get twins just curious why i have more thottle on one side then the other i figured it was so old before counter rotating engines and thats why it has both in standard.
 

wrench 3

Commander
Joined
Aug 12, 2012
Messages
2,108
I'm not sure of '83 but I've run into counter rotating Alpha in '86. I'd run the serial number off of the drive and see what the ratio is.
 

scarabite

Cadet
Joined
Jun 3, 2014
Messages
15
Ok ill be at the boat Saturday putting a new surge actuator on the trailer so ill get both outdrive #`s
 
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