What is missing?

[Davidla]

I am about to travel about 3000km to look at a prospective purchase. Online the vessel states it is powered by a 27hp Yanmar. The photo below has an extra pulley and spline. I am wondering what was on this and why it might have been removed. Any help appreciated.
Cheers,

DL

[Paul L]

Looks like the power take off drives the shaft in the upper right. That looks like it might be a crash high volume waterpump.

[Dsanduril]

Paul beat me to it, looks like a large pump (not related to engine). One hose with the red stripe, the other not in view to the right of the photo between the engine and the silver panel (you can just see the copper elbow appearing to point down).

[Wotname]

What Paul L and Dsanduril said +1

Going by the blue and the light rust marks on the crank pulley, it hasn't been used much.

If it is an impeller style pump, then it is removed as you don't want it to run dry.

However it might be inconvenient (time consuming) to have to fit the upper pulley, belt and adjust it if it is needed in a hurry for a major dewatering activity!!

[Don C L]

Ah! yes you mean an emergency bilge pump? I think I could get that belt on in a hurry!

[Davidla]

Excuse my ignorance but I don't see these on the other boats I am looking at. Should I be worried that the owner felt the need to install this? (I am assuming it is not OEM).

[Dsanduril]

The presence of the pump doesn’t put me off, just indicates a very cautious owner. The rest of the install looks quite nice/taken care of.

I’m guessing maybe the pump pulley had a clutch that failed and so was removed (and maybe not replaced because it never actually got used). But you’d really have to ask the current owner.

[Davidla]

Originally Posted by Dsanduril

The presence of the pump doesn’t put me off, just indicates a very cautious owner. The rest of the install looks quite nice/taken care of.

I’m guessing maybe the pump pulley had a clutch that failed and so was removed (and maybe not replaced because it never actually got used). But you’d really have to ask the current owner.

Thanks, that is my plan, just wanted some background on likely uses. Appreciate all the comments.

[Minggat]

There are engine driven pumps for desal RO. Not just bilge pumps.

[Wotname]

Originally Posted by Dsanduril

........

I’m guessing maybe the pump pulley had a clutch that failed and so was removed (and maybe not replaced because it never actually got used).........

Good point! I didn't think of that possibility.

[Paul L]

Originally Posted by Minggat

There are engine driven pumps for desal RO. Not just bilge pumps.

Yea, but those hoses look too large for that. I suspect it is an emergency bilge pump, aka a crash pump.

[NYSail]

Pardon my ignorance but Where is the sea water pump?

[sainted]

Originally Posted by NYSail

Pardon my ignorance but Where is the sea water pump?

On most Yanmar engines, the water pump">raw water pump is gear driven and on the port side of the engine facing aft. In the photos the op posted, the raw water pump wold be in the lower right corner but it is not visible as it is behind the timing gear cover facing aft.

[Wotname]

Originally Posted by NYSail

Pardon my ignorance but Where is the sea water pump?

Originally Posted by sainted

On most Yanmar engines, the raw water pump is gear driven and on the port side of the engine facing aft. In the photos the op posted, the raw water pump wold be in the lower right corner but it is not visible as it is behind the timing gear cover facing aft.

Correction, the raw water pump on this Yanmar (probably a 3GM or a 3GM30F) is belt driven and can be seen in the lower left side of the picture.

[Wotname]

Raw water pump in the red circle.