saltwater in cylinders

[glenbudden]

I have a 140hp Suzuki motor (1997) which has done 340hrs.<br /><br />After just crossing large wakes from a couple of launches the boat seemed to lose top end power as if she was starving. In the space of 2 minutes the motor died all together. After a couple of minutes I tried starting her and she fired up straight away and cruised as if there were no problems. However a knocking noise then developed in the motor.<br /><br />I took it to our local repairer to get it checked. (It was only serviced 1 month ago). He has informed me that the top piston is damaged due to saltwater. The water was also evident in the other 3 pistons. Apparentley all of the seals/gaskets are OK. The top piston is badly scored but the rings are not damaged. <br /><br />The only explanation I have been given is that the water must have entered the exhaust port when I took a wave over the back of the boat. This seems very odd to me. Has anyone ever heard of this happening? <br /><br />This is the second time this motor has done the top piston. I did not own it the first time it happened (300hrs) but apparently it was a result of water in the fuel. The same mechanic is repairing it this time. As all the rings were replaced at 300hrs the mechanic is just going to repair the top piston. Is this sufficient?<br /><br />Should other things be checked to ensure that a wave over the back was the cause of my problem? I would hate for this to happen a 3rd time. <br /> <br />Your responses/comments will be appreciated<br /><br />Cheers<br /><br />--------------------------------------------------------------------------------

 

[MarineTechStudent]

Re: saltwater in cylinders

how long did you run the motor after it refired, and did you get any warning alarms. This will help in finding the cause.

 

[glenbudden]

Re: saltwater in cylinders

As I initially thought it was a fuel starvation problem I did drive the boat back to the ramp, which would probably be 1/2 an hour. However it did appear to be running on four cylinders again. <br />There were no warning alarms or anything that went off.

 

[Laveread]

Re: saltwater in cylinders

Sorry I can't help you on this issue but I am very interested in the outcome. Nothing scares me more then internal engine problems especially when it comes to salt water intrusion and its effect.<br /><br />It seems odd to me also that the water would enter the exhaust port with just a simple wave washing over the motor. I thought these motors were built to withstand such circumstances and nothing short of a complete submersion of the motor in the water for a number seconds or a cracked head could cause anything like this. In a normal orperating motor I don't think it should happen.<br /><br />A second opinion may be in order here but wait and see what some the responses here will be.

 

[rodbolt]

Re: saltwater in cylinders

hello<br /> saltwater intrusion can come from a variaty of places. loose water from a tell tale hose leak and the water mist being drawn in the carbs. when the stern is dropping rapidly and the next wave is coming at least 1 of the exhaust ports are open to the atmosphere. the exhaust divider plate has bad gaskets or more likely a hole corroded through it. there are many ways to injest water the results are always the same. chopping the throttle and allowing the stern to drop and the backwash to swamp the motor. very common.<br /><br /> good luck and keep posting.