Hi, have a Catalina 30 1981 with the 2 cyl. diesel. During hard healing water will back flow into the oil pan. This is a fresh water boat with no radiator. What is the best way to correct this problem. I am the second owner, so not sure if the po changed anything.
Water in engine oil
- Thread starter ronjh28
- Start date
Several ways to get water into your crankcase
1. Broken inner seal on raw water or fresh water pump - most common.
2. Pin hole in exhaust manifold - engine sucks back water during shut down and subsequent cool down of the engine.
3. Water injection nozzle to close to the static waterline of the boat .... backfills from the exhaust through-hull during high waves or when the boat is heeled waaaay over and the water injection nozzle is momentarily, etc. below the heeled waterline when sailing and engine NOT operating.
4. Blown engine head gasket - usually between two cylinders and which 'communicates' with the cooling system.
5. Cracked engine block.
TASTING the water for if its salt water or fresh water help will point you in the correct direction of the source of the water. Fresh water circuit Cooling system expansion tank low - seems to be missing water?
1. Broken inner seal on raw water or fresh water pump - most common.
2. Pin hole in exhaust manifold - engine sucks back water during shut down and subsequent cool down of the engine.
3. Water injection nozzle to close to the static waterline of the boat .... backfills from the exhaust through-hull during high waves or when the boat is heeled waaaay over and the water injection nozzle is momentarily, etc. below the heeled waterline when sailing and engine NOT operating.
4. Blown engine head gasket - usually between two cylinders and which 'communicates' with the cooling system.
5. Cracked engine block.
TASTING the water for if its salt water or fresh water help will point you in the correct direction of the source of the water. Fresh water circuit Cooling system expansion tank low - seems to be missing water?
It only happens when we are heeled way over and the motor is off. the cat 30 motor is very low under the water line. we sail in fresh water{michigan} so tasting would not help. We pull the plug on the mixing box and it stopped it from happening.so it must be coming in from the box. ie backflooding it. Does anyone have a good diagram of how the water lines should be routed on a catalina 30 without a closed system?
OK - possibly: 3. Water injection nozzle to close to the static waterline of the boat .... backfills from the exhaust through-hull during high waves or when the boat is heeled waaaay over and the water injection nozzle is momentarily, etc. below the heeled waterline when sailing and engine NOT operating.
The classical way to correct this situation is to apply/build a 'dry stack' after the engine - a short run of black iron pipe thats typically about 18-24" straight up / vertical from the exhaust manifold which then is connected to a 90° elbow thats connected to your (new) water injection elbow, the water connection to the injection elbow is from a 'siphon breaker' and is mounted 'above' the injection elbow. All this is DIY built of black iron/steel pipe, common elbows and 'short' or 'close pipe nipples, ...... and usually terminates into a cast aluminum Westerbeke injection elbow.
Most Yanmar dealers usually have this Westerbeke cast aluminum injection elbow in stock ... as engine backflooding is a common problem for boats with engines mounted BELOW the waterline. The drystack discharges the exhaust system well above the water line, even when the boat is well heeled over.
Sequence: Exhaust manifold - threaded flange adapter for 1.5" pipe (Obtain from your engine dealer) - 1.5" close nipple - 90° 1.5" elbow - 18-24" 1.5" threaded pipe - 90° elbow - 1.5" close nipple - Injection elbow .... all covered with steam pipe 'lagging' to help retain the heat of the assembled 'dry stack', use LOTS of lagging as dry-stacks get VERY hot.
The classical way to correct this situation is to apply/build a 'dry stack' after the engine - a short run of black iron pipe thats typically about 18-24" straight up / vertical from the exhaust manifold which then is connected to a 90° elbow thats connected to your (new) water injection elbow, the water connection to the injection elbow is from a 'siphon breaker' and is mounted 'above' the injection elbow. All this is DIY built of black iron/steel pipe, common elbows and 'short' or 'close pipe nipples, ...... and usually terminates into a cast aluminum Westerbeke injection elbow.
Most Yanmar dealers usually have this Westerbeke cast aluminum injection elbow in stock ... as engine backflooding is a common problem for boats with engines mounted BELOW the waterline. The drystack discharges the exhaust system well above the water line, even when the boat is well heeled over.
Sequence: Exhaust manifold - threaded flange adapter for 1.5" pipe (Obtain from your engine dealer) - 1.5" close nipple - 90° 1.5" elbow - 18-24" 1.5" threaded pipe - 90° elbow - 1.5" close nipple - Injection elbow .... all covered with steam pipe 'lagging' to help retain the heat of the assembled 'dry stack', use LOTS of lagging as dry-stacks get VERY hot.
I agree with Rich, as he describes exactly how my 5411 diesel is plumbed on the exhaust side. My engine has never had a problem with back flow, so I have to assume that it is the Westerbeke cast aluminum exhaust elbow that fits between the exhaust riser pipe, & forms the gooseneck anti siphon section of the exhaust which then runs to the water muffler box. Perhaps your 5411 has a replacement exhaust riser & gooseneck built from standard threaded steel pipe, & does not have then Westerbeke elbow as described. This may be what you need to prevent the back flow. But if I recall the height of the water muffler box is well below the level of the exhaust riser, so I'm surprised that you are getting water backflow while heeling. Since the water muffler is slightly to port side, it must be when the boat is heeling over hard to starboard, that the water muffler is then raised higher then the exhaust riser to allow water to backflow.
Lastly, the only time that I had an unusual water backflow, was when I first bought our boat & a failed check valve that is built into the galley sink vent failed, & allowed raw water to pump up through the galley sink drain. It freaked me out because water was overflowing the sink drain & I thought I had a major leak on my hands. Turns out that this tiny little 1/4" diameter piece of rubber membrane with a pin hole in the center of it had failed causing raw cooling water to siphon up through this galley sink vent.
But I believe your problem will be cured by just extending the height of the exhaust riser & elbow a few inches to prevent water backflow when heeling, since as long as the riser is higher then water muffler it will prevent water intake.
Lastly, the only time that I had an unusual water backflow, was when I first bought our boat & a failed check valve that is built into the galley sink vent failed, & allowed raw water to pump up through the galley sink drain. It freaked me out because water was overflowing the sink drain & I thought I had a major leak on my hands. Turns out that this tiny little 1/4" diameter piece of rubber membrane with a pin hole in the center of it had failed causing raw cooling water to siphon up through this galley sink vent.
But I believe your problem will be cured by just extending the height of the exhaust riser & elbow a few inches to prevent water backflow when heeling, since as long as the riser is higher then water muffler it will prevent water intake.