OX66 adjust engine idling speed

[mesias_yam]

Hello there,

The engines are 2001 OX66 LX/SX225TXRS.

Is this procedure supposed to be done in the water or is it OK to do it on muffs?

The issue is (or not) after doing a sync of throttle valves, adjusting the TPS voltage and setting the idle speed in the 700 rpm range while on muffs, the engines are down to idling at 500 rpm when in the water. Is this normal?

Thanks in advance!

[scofflaw]

Normal if that 500 is an in gear number

[99yam40]

Not sure on those motors, but the back pressure on exhaust of the lower unit being submerged affects the running at idle of the motor, even tho it has idle exhaust relief ports.
most say to do final setting in the water after motor has warmed up

[mesias_yam]

They were idling at 500 in neutral... I noticed them at some point down to 400 in gear. The service manual is not clear whether this should be done in the water or not. I noticed no issues throttling up from this low or down to it, they never died on me or anything similar.

[scofflaw]

700 in neutral in the water