Mercury CNC props Bblades MRI scan
07-17-2019, 10:19 AM
#12
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One drive is chain driven, the other is gear driven (to change rotation). The gear drive box is less efficient than the chain drive and will extract more power but I wouldn't think it would 15%. Do you know which side the gear drive box is on?
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07-17-2019, 06:34 PM
#14
I believe the ZF 280's are gear only. Basically one is in reverse and one in forward. Typical three shaft transmission with an input, a lay, and output shaft. The side that's down on RPM is the one that has more gear contact to rotate same as the motor. I can't imagine it's 15% though.
07-17-2019, 06:39 PM
#15
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I believe the ZF 280's are gear only. Basically one is in reverse and one in forward. Typical three shaft transmission with an input, a lay, and output shaft. The side that's down on RPM is the one that has more gear contact to rotate same as the motor. I can't imagine it's 15% though.
What horsepower are you making?
07-17-2019, 06:46 PM
#16
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Hold on, let’s back up a bit......
I am talking about the ASD8 drives, not the transmissions.
So are you saying the counter rotation is accomplished in the transmissions rather than the drives?
I am not well versed on the ASD8 but assumed it was similar to the ASD7 which uses gears to reverse rotation on one drive and a chain/sprocket combo on the other drive.
I am talking about the ASD8 drives, not the transmissions.
So are you saying the counter rotation is accomplished in the transmissions rather than the drives?
I am not well versed on the ASD8 but assumed it was similar to the ASD7 which uses gears to reverse rotation on one drive and a chain/sprocket combo on the other drive.
07-17-2019, 06:48 PM
#17
They are the 480HP 950TQ rated motors. I just had the the first 250 hour service done on them. We checked the valve lash and injectors, and a few other things. I'm really leaning towards the props, it makes the most sense. My only experience with surface drives is with RC boats. I do know that a very small change in prop makes a huge difference. Granted, that probably not the best comparison.
07-17-2019, 06:57 PM
#18
Hold on, let’s back up a bit......
I am talking about the ASD8 drives, not the transmissions.
So are you saying the counter rotation is accomplished in the transmissions rather than the drives?
I am not well versed on the ASD8 but assumed it was similar to the ASD7 which uses gears to reverse rotation on one drive and a chain/sprocket combo on the other drive.
I am talking about the ASD8 drives, not the transmissions.
So are you saying the counter rotation is accomplished in the transmissions rather than the drives?
I am not well versed on the ASD8 but assumed it was similar to the ASD7 which uses gears to reverse rotation on one drive and a chain/sprocket combo on the other drive.
07-17-2019, 07:16 PM
#19
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Ok, well excuse my ignorance and I learned something here.
If you have #6 props I have a spare set if you’d like to try them.
They are considerably smaller than what you are running though.
If you have #6 props I have a spare set if you’d like to try them.
They are considerably smaller than what you are running though.
