Volvo penta md5a water in oil?

[elsky79]

Hey guys, I'm getting going on the balboa 26 restoration and I've come to the engine. I managed to get the lines all bled and got her warmed up enough to crank this morning. She runs pretty good from the way it sounded. I was pleased. Although, I didn't have water sucking into the engine cooling passages so I shut her down. I tried several things then wound up using the garden hose to pump water straight into the cooling passages where I managed to have a nice stream flowing out the exhaust. I thought great I've got it now. But here's the thing. The engine is getting water in the oil crankcase when I crank it up. Is there a good place to start looking for a bad seal or bad head etc. or is this simply my dumb fault for using a garden hose and filling the exhaust port with water...leading to the crankcase filling up.

I'll also add. When it's running you can pull the dipstick and it will quickly fill with water then overflow.

Of course once I saw this I quickly Shut her down and won't try anything until there is fresh oil and filters in place.

Any help on the cause of water into te oil is greatly appreciated. Thanks in advance!!

-tyler

 

[Charles Erwin]

A definitive diagnosis is impossible from this distance - but

First - amend your test method. Never pressurize the pump with a garden hose. Use the garden hose to fill a bucket then use the motor's pump to withdraw water from the bucket normally through the motor and overboard.

If this amended method results in the same crankcase flooding then remove and reseal the cam driven water pump. Be sure the shaft is not scored because if scored it will leak.

With this pump design - if the first seal (the water side) fails then water flows past the second seal (the oil seal) and into the crankcase (see the diagram in the workshop manual.) My bet is the pump seals have failed in your case.

If not - then you surely have a failed head gasket or a fractured casting.

Charles

ps please let us all know the eventual outcome

 

[elsky79]

Will I need to prime the system in order to get the motor to suction water out of the bucket? It didn't seem to have suction. Is that a good indication the water pump needs rebuilt as well?

 

[ALNims]

You may want to contact the engine manufacturer technical support website for possible source of the water intrusion into the oil sump. I would strongly urge to NOT run the engine again until you have found the source of the leak.

 

[Charles Erwin]

Once the pump is fixed no priming will be necessary. And anyway the bucket will be above or even with the level of the pump. If the bucket is above the pump don't let water siphon from the bucket when the motor is not running.

The pump will not move any water if the shaft seal or impeller has failed. An impeller and new seals are simple enough to install. As to whether these items will restore pump performance - it is impossible to say until you have examined the pump body for worn surfaces. For sure - if the pump does not move water then it obviously cannot put water in the motor whereas a pressurized source (garden hose) will.

Certainly all water must be removed from the crankcase pronto.

Charles