Volvo Penta 2003 loss of coolant

[Tcubed66]

Originally Posted by jamhass

A comment on the suggestion that the seals on the water pump">raw water pump is a possible issue:

The raw water pump on the 2003 does NOT directly communicate with the oil sump. There are 2 seals on this pump, one for the water side, another for the oil side. There is a large void between the two. Should the water seal leak, the water exits through the void, missing the oil side completely.

There is a small chance that the void can become fouled with slat such that a leak could make it to the oil side, but the hole is so large on this pump that it is highly unlikely that this would occur.

I have seen this happen on other engines, but the VP2003 pump has a very large drain void for such leaks.

Exactly.

[cam11585]

Hi All,

Thanks for the advice. I'm starting with rebuild of the raw water pump as step 1 in this diagnosis. I will be replacing the shaft, bearing, and seals. There is a plastic spacer in between the water and oil seals, in the "void" part of the pump. Mine is flat on all sides. However, in pictures and videos I have found online the spacer has "teeth" and the o ring actually sits in the teeth. This serves to force water through the void instead of allowing it to pass through to the oil side. Interestingly the schematic I have for the raw water pump doesn't show this spacer at all.

Has anyone encountered this on your VP 2003? Was there a design change? Anyone know the part number for this spacer?

[MicHughV]

Speaking from experience, I had raw water enter the VP engine from the exhaust. The exhaust manifold is raw water cooled, but some internal corrosion had occurred, and once the engine was shut off, water seeped into the cylinders thru' the valves, being as that the anti-siphon valve was gooped up. Seized the engine up completely. Amazingly enough, after removing the cylinder head, removing the water, draining the oil, and banging on the piston with a sledgehammer, put everything back together, using the original head gasket, and damn if it didn't fire right up. Water in oil usually results in a milky type appearance....hard to miss.

[Tcubed66]

I’ve seen some with and without. Not exactly sure what the purpose is for the oring or/and spacer is for.

[cam11585]

So I got the raw water pump rebuilt and installed. The pump seemed to be functioning normally but initially there was still no water dumping out through the exhaust. After some investigation I traced the problem to a clog in the raw water pipe, just before it dumps into the exhaust riser. After busting up the clog by poking a screw driver in there and reassembling the raw water flow was normal. The clog seemed to be rust and scale, it came out black almost dirt like. I then flushed the oil several times and the water intrusion seems to have stopped. So I guess we're all good, but...

I STILL HAVE NO IDEA HOW WATER WAS GETTING INTO THE OIL

Any ideas? I'm nervous! The rest of the raw water system and the heat exchanger seems to be clear, including the siphon loop.

[fourlyons]

Originally Posted by Tcubed66

I’ve seen some with and without. Not exactly sure what the purpose is for the oring or/and spacer is for.

They are there as a "slinger" (my word for it) to deflect and throw any water leaking/spraying from the water seal away from the oil seal.

[jamhass]

If, after properly gone through the rest of the systems you still have salt water getting into the oil, I have to ask ... Do you have an oil cooler?

My 2003T did and it died (twice). In my case oil leaked out, not salt leaking "in", however it is conceivable that such might occur if there was an internal leak in the oic cooler that allowed salt water to drain into the oil.

Very difficult for me to envision how this could occur, but if all other options have really been eliminated, look for an oil cooler. Possibly cost near as much as a new engine (parts not likely available) but when I redid mine last, I replumbed the engine and went with aftermarket Heat exchanger and oil cooler both.

[deblen]

If the inlet pipe at your exh. elbow was blocked as you say,the raw water pump would have built up excess pressure in piping.
This may help suss out the 2003 cooling system:
http://coxeng.co.uk/wp-content/uploa...hot-water1.pdf

[deblen]

Another thread:
https://forums.sailinganarchy.com/in...2003-overheat/