CD 31 diesel problem

[len]

i managed to get water inside my engine today while running it on the hard as part of pre-launch prep - i'm not entirely sure how it happened, the diesel mechanic at the yard thought i was siphoning water (from a bucket on the forward cockpit seat; this is how i've run the engine on the hard for 10 years because the water pump wouldn't pull water through - i changed the water pump this year and the mechanic thinks that did it) - the engine is a universal M25 with a heat exchanger system -

so my first question is: did the water get in through the shaft that drives the raw water pump? and if not, how (i knew water was in the engine when it started running out of the air intake)

i took out the fuel injectors and cranked the engine which blew dirty water all over the place and the engine did run and seemed fine after bleeding the fuel system

my second question is: do i need to do anything else

thanks in advance

len



md.frel@nwh.org

[len]

in thinking this through further it seems to me water could only get in the engine via the exhaust valves and it seems plausible that there would be enough pressure from a bucket well above the highest point of the exhaust system IF the impeller in the water pump would allow water to keep flowing past it even when it is immobile (because the engine was off) -

does this make sense?

len



md.fre@nwh.org

[Denny]

If you got water coming out your air intake there is only one way it got there and that is by pumping it into your exhaust manifold from the water lift muffler. If you continuously crank your engine over without starting, your water lift muffler will fill up and then continue to fill right into the exhaust manifold and then into the exhaust valves and then out the air intake valves and then out the air intake filter. It takes exhaust pressure from your engine to push the water from the water lift muffler out the back of your boat with the exhaust gas.

So, if your engine does not start after a few tries, be sure to take the plug out of the water lift muffler and let it drain into the bilge. You can damage your engine good if you try to compress this water with the pistons.

Get the water out of the cylinders by slowly hand cranking and then continue to hand crank with the exhaust valves held open with the manual bypass lever. Do this until dry with air filter removed and clean and re-oil the air inlet filter. Find out why the engine does not start and get it running as soon as possible to prevent corrosion.

If the water pump shaft seal leaks, it can leak water into the crankcase not the cylinders.

[John R.]

i managed to get water inside my engine today while running it on the hard as part of pre-launch prep - i'm not entirely sure how it happened, the diesel mechanic at the yard thought i was siphoning water (from a bucket on the forward cockpit seat; this is how i've run the engine on the hard for 10 years because the water pump wouldn't pull water through - i changed the water pump this year and the mechanic thinks that did it) - the engine is a universal M25 with a heat exchanger system -

so my first question is: did the water get in through the shaft that drives the raw water pump? and if not, how (i knew water was in the engine when it started running out of the air intake)

i took out the fuel injectors and cranked the engine which blew dirty water all over the place and the engine did run and seemed fine after bleeding the fuel system

my second question is: do i need to do anything else

thanks in advance

len

Having not been there and not witnessed all that went on with trying to run this engine when all this took place means my view on this would be that perhaps the engine was cranked continuously with the engine decompressed which would allow the cooling water (raw) to back up in the exhaust manifold then from that point enter the cylinders since there would be no compression to blow the water out of the manifold and exhaust. Unfortunately, this happens all to often.

I'm not especially familiar with the workings of the Universal but the freshwater cooling and raw water side are basically the same on most engines of differing brands. You mention a shaft that runs your raw water pump and I assume that shaft has a seal where it enters the engine block. Even if that seal were to fail it would take quite awhile to fill that crankcase full of water to the point where it would spray out the injector ports.

The first thing you should do is change the oil and filter several times, running engine briefly betwen changes. Then pickle the engine so everything is doused with an anti corrosive lubricant. From that point sit down and really try to determine exactly what went wrong. After you determine the cause and take the corrective measures then run the engine some more and again change the oil and filter. You should repeat that oil and filter process several times over the next few weeks. After a month or so of good use have a compression test done. Compare it to factory specs and note the differences if any. A few weeks or so later repeat the compression test again and see if any earlier differences have changed. If they have then you know you have a progressively worsening problem. If not, consider yourself very lucky. However, keep an eye on the exhaust for several months looking for smoking. If you see any make a note of the color, blue, white or black. Blue or white and you've got a fairly good shot at a serious problem, black and I wouldn't panic, just some adjustments necessary.

Any hard starting in the future will manifest as a late blooming problem due to the flooding. The same goes for the fuel systems.

Most importantly you better hope no water made its way into the injector pump. If so, get ready to purchase a new one in the near future.

Good luck.

[len]

john

thanks for help - i'm unfamiliar with "pickle the engine" - ? process

len



md.frel@nwh.org

[Larry DeMers]

Denny,

Good points and advice. I just wanted to emphasize one thing you mentioned. If the water pump seal is leaking water out of it, there is a really good chance it is also leaking past the second seal to the crankcase (as you mentioned). The consequences of this, at least on Volvos, are catastrophic in that the water mixes with the oil, and that will wear the entire engine very quickly, ruining it. So unless you want to replace that engine in toto, heed that dripping pump and
replace the seals (inner and outer).

Larry DeMers
s/v DeLaMer
Cape Dory 30

If you got water coming out your air intake there is only one way it got there and that is by pumping it into your exhaust manifold from the water lift muffler. If you continuously crank your engine over without starting, your water lift muffler will fill up and then continue to fill right into the exhaust manifold and then into the exhaust valves and then out the air intake valves and then out the air intake filter. It takes exhaust pressure from your engine to push the water from the water lift muffler out the back of your boat with the exhaust gas.

So, if your engine does not start after a few tries, be sure to take the plug out of the water lift muffler and let it drain into the bilge. You can damage your engine good if you try to compress this water with the pistons.

Get the water out of the cylinders by slowly hand cranking and then continue to hand crank with the exhaust valves held open with the manual bypass lever. Do this until dry with air filter removed and clean and re-oil the air inlet filter. Find out why the engine does not start and get it running as soon as possible to prevent corrosion.

If the water pump shaft seal leaks, it can leak water into the crankcase not the cylinders.

demers@sgi.com

[Larry DeMers]

Yup..you have head pressure provided by the bucket. The impellor is a vane pump, so the water will flow straight thru on it's own with head pressure.

What was wrong with the pump that caused you to use the bucket above the engine trick? That probably should have been fixed first, then leave the bucket on the salon's sole and pump the water from there up to the engine. Remember to not crank too long without the engine running to rid the muffler of the accumulated water..or unscrew the drain plug on the muffler body and allow it to drain out (will get some diesel smoke that way). Ahh engine lessons..fun huh? hee


Larry DeMers
s/v DeLaMer
Cape Dory 30 Been there...Done that..hope not to repeat it agin!

in thinking this through further it seems to me water could only get in the engine via the exhaust valves and it seems plausible that there would be enough pressure from a bucket well above the highest point of the exhaust system IF the impeller in the water pump would allow water to keep flowing past it even when it is immobile (because the engine was off) -

does this make sense?

len

demers@sgi.com

[John R.]

john

thanks for help - i'm unfamiliar with "pickle the engine" - ? process

len

Basically load it up with an anti-corrosive when running. Just as if you were putting it in storage. Use Corrosion X, good stuff.