Help!! Perkins4-108/Westerbeke wont bleed

[GordMay]

Greetings and welcome aboard the CF, agolbitz.

Glad you got it solved.

[jpendoley]

We did and it purred through a sloppy passage south. On the last leg down the coast and reflecting that cruising sometimes really is traveling to exotic places and working on boats. The admiral (Agolbitz) is still coming to terms with this reality and does have some helpful suggestions for my future preventative maintenance routine[emoji16].
Regarding the primary rancor, when it does begin to accumulate sediment in the bowl and needs to be drained-is it always the case that the system must be bled? I would think draining from the bottom would pull in fresh fuel via the vacuumed created by the draining fuel-is that correct? The original air entry was due to changing primary and secondaries, but routine draining of water/sediment should be possible without bleeding-is that true or am I dreaming?

[Poche]

Well, I am new to servicing a 4108 or any diesel.
What does turning off the raw water do? Doesn't that circulate in it's own system?

[Lepke]

If you crank excessively without starting, the water pump">raw water pump can overflow the exhaust elbow and fill any cylinder that has an open exhaust valve. Water in the cylinder can hydraulically lock the engine. Rods can get bent. So you shut off the intake thru hull for the pump until you're ready to start.

A lot of water mufflers need the exhaust flow to force the water out.

[Poche]

What is excessively? More than a few five second cranks? More than ten cranks?

[donradcliffe]

Originally Posted by jpendoley

Regarding the primary rancor, when it does begin to accumulate sediment in the bowl and needs to be drained-is it always the case that the system must be bled? I would think draining from the bottom would pull in fresh fuel via the vacuumed created by the draining fuel-is that correct? The original air entry was due to changing primary and secondaries, but routine draining of water/sediment should be possible without bleeding-is that true or am I dreaming?

Routine changing of the racor filter or draining the bowl does not usually require bleeding IF you fill the filter housing to close to the top with diesel before you replace the cover. Draining the bowl usually requires removing the top cover before any liquid will flow out the drain.

[Junglebike]

Originally Posted by Lepke

If you crank excessively without starting, the raw water pump can overflow the exhaust elbow and fill any cylinder that has an open exhaust valve. Water in the cylinder can hydraulically lock the engine. Rods can get bent. So you shut off the intake thru hull for the pump until you're ready to start.

A lot of water mufflers need the exhaust flow to force the water out.

I did not know that - thanks for possibly saving my engine someday!

I had a long fight with a 4108 after a filter change once - I couldn't get any flow at all to the injectors and couldn't figure out why. Turned out the filter I put in was defective and didn't flow. I never did figure out exactly where the blockage was but with a (second) new filter everything was back to normal.