Intake water on Suzuki DT75

[bbel]

Hi,<br />I recently had a serious problem with my engine. I was driving fast, and by mistake, I cut the engine with the security switch. The engine naturally stop.<br />But when I tried to switch on the engine, the engine turn but it never run. I had to call the coast guard...<br />At home, I've checked the sparks and the three ones where full of water. I've opened the top of the engine and the three cylinders where also full off water.<br />I suppose that the water came in by the exhaust.<br />How can it bee ?<br />Is there something I can do ?<br />Thanks,<br />Bruno.

 

[jim dozier]

Re: Intake water on Suzuki DT75

The water probably came in the exhaust ports when the wake washed over the back of the engine. If the engine had still been running the pressure of the exhaust would likely have kept it out of the cylinders. If the water was removed quickly and the engine restarted I wouldn't think much damage would occur but I have no experience with this. If it sat in the cylinders for days while waiting for a diagnosis there is probably rust occurring on the cylinder walls and it may be more problematic.

 

[bbel]

Re: Intake water on Suzuki DT75

The problem is that when it happened the engine refuse to start again. I can't imagine that it's a normal situation. Perhaps there is a "valve" somewhere deficient ?<br />Does the exhaust goes directly to the sea ?

 

[EZLoader]

Re: Intake water on Suzuki DT75

The engine refused to start again because you had all that water in your spark plugs and cylinders. If your motor was real hot and the cold water rushed inside it might have caused some other damage too (cracking). <br /><br />Unless you have the skill to check and fix it yourself I'd use a marine mechanic on this.

 

[bbel]

Re: Intake water on Suzuki DT75

I've open the engine (cylinder head) and all is ok except the water (I have a good experience on 2 strokes motorbikes). I've washed all and close with a new gasket and plugs.<br />But now, I don't want to return to drive until I understand what appened. If, for emergency, you stop the engine with the security switch and then the engine refuse to start because it is full of water, there is something I've not understand.<br />Did this problem happened to somebody else ?

 

[jim dozier]

Re: Intake water on Suzuki DT75

The exhaust is open to the water. If the engine sits low in the water and you stop quickly with the engine off, depending on the boat/engine setup the wake can wash over the back of the engine and raise the water level in the exhaust till it comes in the exhaust ports. If the engine is running the backpressure would prevent this. To prevent this you might investigate whether the engine is too low on the transom and also check the trim of your boat, perhaps you are tail heavy. If it did happen again, pull the spark plugs and get all of the water out and it would probably start up.<br /><br />Where is the antiventilation plate on the lower unit relative to the bottom of the hull?

 

[bbel]

Re: Intake water on Suzuki DT75

I've checked the position of the engine on the hull regarding what preconise Suzuki, and it is ok.<br />From memory (the boat is not at home), the antiventilation plate is exactly at the bottom level of the hull.<br />Something strange is that I've bought this to boat to a friend witch had never had this problem !...

 

[bossee]

Re: Intake water on Suzuki DT75

Hi,<br />Assuming it is like jimd suspect and you get the outboard running again You could do some tests at lower speeds and pull the string to security switch and have a person watch how water flows in stern when engine stop. That should give You an idea what could be possible or not possible regarding water beeing able to flow into the engine or not.