Originally Posted by vwkevin
Thanks for all the great info guys. My engine is the saltwater version without the heat exchanger. I went ahead and overnighted the stainless elbow so I will pray that does the trick, but I'm not feeling overly optimistic now that I have had a chance to read up on this more.
Not having replacement O'rings for other parts
of the system is really going to complicate things. Anybody know of a source for at least the thermostat o'ring and the o'rings for the tube that connects the thermostat to the exhaust elbow? It looks like West Marine
has to special order the seals so they wouldn't arrive on time. I would have to find something somewhere around Long Beach...
I have attached some photos. I do not see any form of strainer for the raw water intake which concerns me. It just runs from the seacock, to a T that feeds the dripless shaft, then into or under the transmission and off to the port side of the engine...probably directly to the water pump. Could this really be possible? Maybe this further explains the obstruction but I hope not. Also, does the raw water intake cool the transmission somehow or just run underneath it? I see that the hose running to the dripless shaft is probably underrated pressure wise...maybe the other ones are as well?
Please scour over my attached pictures and see if there's anything else you can spot. Thanks!
All in all,your 2003 looks very dry & good.
Since you are in a rush,try curing the problem without taking anything off the engine. I can almost guarantee you will need parts-seals,gasket,etc. if you do.
So-try to narrow down where the restriction is by removing hoses & checking output in the RW system.
The circuit is as follows :
In the seacock,thru the Tee,thru the gearbox
& up to the bottom of RW pump. This is the suction side.
Remove the hose that comes from RW pump output & check flow at 1000RPM. Should be a good full pipe.
After the pump,there is a split in flow. When cold,water only flows into the front of the engine,along a perforated tube inside the engine & out the rear of engine,thru a copper tube & into the port side of the elbow. This path can build up crud.
There is no flow thru the T-stat until it warms up. Then you get a parallel flow thru that horiz. tube between T-stat & front of elbow.
See my earlier posts & links for exploded views.
Possible problems noted from your pics:
Pic 1. Img 4113
1. The raw water does indeed go thru a cooler built into VP gearbox & this is normal.
2. The water hose from Tee to Stuffing box is on the suction RW line.Usually this lube feed comes from the pressure side of RW system.
Suggest clamp it off with a vicegrip to see if RW flow is being reduced because air/water is being sucked from stuffing box.
3. Hose from TEE to gearbox is partially collapsed. Replace it with suction rated hose.
4. You should install a 3/4" - 1" RW filter ,above the waterline & between the Tee & gearbox in.
5. Check the thru hull/seacock for blockage,growth etc.
If you are organized.this can be done while afloat.
6.Double clamp all RW hoses.
7. Exhaust hose is partially kinked. These can collapse inside & still look good outside.
Pic 5 Img 4142
I've never seen a plug
on the T-stat housing. Custom air bleed? Harmless,I guess.
Pic 6 Img 4145
Looks like a stock VP cast iron elbow-not SS. If you replace,recommend SS from HDI?.
You will need a new elbow to manifold gasket(get 2). The gasket
is not re-usable & is hi-temp material.
Recommend replacing any rubber ring seals.
The 4 metric bolts that hold the elbow on can be corroded away & need replacing.
Pic 6 Check behind that metric plug
just to right of T-stat for a zinc.
Check for a zinc plug below the alternator
. Replace annually in RW cooled engines.
I get my parts from Volvo Penta Schematics - Marine Parts Express
because they are close & provide great online exploded views of engine.
But any VP dealer will be able to fix you up.
Good luck/ Len