WATER IN FOREWARD CYLINDER

[JIM KEITH]

I HAVE A 1989 HUNTER 30 WITH A 2GM20F YANMAR DIESEL. WHILE INVESTIGATING A MISS DURING STARTING I FOUND WATER IN THE FRONT CYLINDER. ENGINE RUNS GREAT AFTER APPROX. 50 REVOLUTIONS. ANY IDEAS?

 

[Frank Wang]

Three possibilities

1) If it is salt water, water could come from the exhaust. Salt water pump delivers water to the exhaust system to cool the exhaust. Exhaust pipe is below the through hull exhaust fitting. Therefore, if the engine is not running at certain RPM, there is not enough pressure to push salt water out of the exhaust system. Water will accumulate there. If you sail with water in your exhaust system in rough water, you may have a chance to have water back splashed into your cylinder.2) If it is fresh water, it could be condensation. The amount should be very little.3) If it is coolant, there might be a leak in you engine.1) and 3) are serious problems.Just my two cents.Frank

 

[Ed Allen]

could be a head gasket. but it needs attention now

delaying will cause catastraphic problems!

 

[Robin]

I had the same problem a while back

If you search the hunterowner archives you'll find my psychotic rantings about how I thought I destroyed my engine. I finally found that any time you are going to have to start your yannie for more than 30 seconds (bleeding, etc) you should close the raw water intake to prevent the backflushing of all the sea water (which the impeller and pump does not build up enough pressure to pump all the way out of the exhaust loop) into the cylinders via the exhaust manifold (which I would go ahead and pull off and examine because yannie designed it to last 3-5 years depending on water conditions). I ended up tearing my engine down to the block and replacing all the gaskets and checking everything out ( a big hassle) and found nothing wrong. What I would do is pull the injectors, close the sea cock for raw water intake and manually turn the flywheel (in the correct direction). All of the sea water (if that is what it is) will pump out then you will have to change the oil and filter, bleed and crank the engine and let it run for a while (just to normal operating temps)and circulate the oil, then change it and the filter again. Let me throw in the standard clause that I am not an expert but I did have the same exact problem (if it is sea water) on my 3gmf30 and this is what I had to do after putting the engine back together. This would have fixed it without tearing the engine apart. Good luck!

 

[John Visser]

a couple of comments

If it is sea water (just taste it to find out - condesation will have no taste, coolant is sweet, sea water is salty - a bit on your tongue won't hurt you):1. Excessive cranking can fill hte water-lift muffler and eventually back up into the exhaust manifold. The muffler should have a drain cock, and it should be drained after a lot of cranking, and also before winter storage.2. If a following sea drowns the engine, the exhaust system is not properly designed. There should be a loop in the exhaust hose way above the water line, and if necessary, a flap on the exhaust port. Incidentally, the raw water line to the exhaust riser should have a vented loop.3. Don't pump the seawater out of the exhaust or injector port using the engine - drain the muffler. 4. The engine can survive sea water if it does not sit for any length of time. If you discover it soon, and just run the engine for a while, you should be O.K. Then, find and fix the fault that caused it.