No thermostats in SX230, is it ok to flush with no ignition ?

[Donny Hudson]

I recently had my boat sitting for about 3 weeks without being able to flush my engines because both motors would not crank. I was concerned, because I use my boat in salt water and my mechanic flushed my engines without the thermostats and no ignition before we started repairing my electrical issue. He said it would be ok.

I was skeptical because I have read on this forum so many times about back pressure driving water back into the engines and causing water in the oil, hydrolock etc.

Well after the flush I do not see any signs of milky oil at all or any problems.

I want a second opinion, is it correct that we can flush the engines safely with the ignition off as long as the thermostats are not in the motor?

PS. Both motors are working great it was only a bad main ground. Looking forward to hearing your answers to my original question.

 

[WREKS]

I agree with your mechanic. Your pushing water through the entire cooling system. However, I would not do that for more than a minute. The hot exhaust helps dry up the cooling system inside. I think more damage is done to these engines by residual water from flushing than by the salt water being flushed out.