Volvo Penta 2003 - Exhaust Restriction/Poor Water Flow

[vwkevin]

I recently purchased a first sailboat and unfortunately had some mechanical problems get past my surveyor. I need to move the boat roughly 12 hours away with a delivery captain very very shortly, so I'm looking for some quick advice on getting the boat seaworthy. I already have unlimited towing with BoatUS but I would prefer not to have to use it. Engine is a Volvo Penta 2003.

Anyways, it appears there is some sort of water flow restriction (see video) which is causing a lot of steaming and a somewhat pitiful amount of water coming out the exhaust (a Vetus Waterlock). I think I've got a mechanic coming by to change out or clean the exhaust elbow/riser, but are there any other common areas of restriction that I should check or have checked if that doesn't do the trick? Could the heat exchanger or some other component be majorly contributing? The water impeller has already been changed. One thought I had was that perhaps the thermostat isn't opening causing the overheating. I know the sacrificial anode on what I believe is the thermostat housing isn't looking good...would that indicate anything? The pipe connecting the thermostat housing to the exhaust elbow also shows some corrosion around the seal on the exhaust housing end.

Also, if my mechanic falls through, what is the process for servicing the exhaust elbow myself? Close the seacock, undo the hose going to the elbow and drain the water that comes out of it, remove the exhaust elbow bolts, clean with carb cleaner/acid/brush, reinstall elbow, reinstall hose, open seacock? Is there any concern for air getting in the system? I assume no?

Thanks!

[shakey doug]

Start at seacock end check water flow then clean strainer make sure cover is properly sealed, now raw water pump check impeller condition also make sure running surface of face plate is not badly scored. Use only a copy paper thick joint here. Do easy/ quick things first. Report back.

[olaf hart]

Is it a freshwater cooled or a saltwater cooled engine, VP made both for this model?

The exhaust elbow is not serviceable, needs to be replaced if it is blocked. The water passages are cast outside the exhaust tube, they clog up and you can’t get into them.

In the saltwater engine, it is common to have salt scale block the hoses and tubes, take them off and clean them out.

You also need to check the pump impeller, may as well replace it while you are there. Don’t forget the paper washer.

If it is a freshwater engine, you also need to inspect the heat exchanger.

Another cause of overheating in the saltwater engine is the wrong thermostat. The salt one is 140 degrees and the fresh one is 170 degrees, easy to get wrong. I don’t think your problem sounds like the thermostat though.

That is the extent of my fun times with my 2003. I have a spare exhaust elbow which I clean out with neat HCl when I get it home blocked, works so far and I just swap it over with the other one every few years. The acid may eventually rot through, but my original one had managed to rust right through just with saltwater and the wrong thermostat.

If you change your one it may be worth a go, it’s good to have a replacement, but remember my advice about cleaning it with acid is worth what you have paid for it.

[olaf hart]

My surveyor ran this engine in his charter boat generator, said to see replacing the exhaust elbow as a maintenance item every three years.

[vwkevin]

Thanks for the information so far. Very helpful! The engine is salt water cooled.

[drummer81]

Could this be helpful? https://youtu.be/WjXNsoIIjo4

[drummer81]

Originally Posted by drummer81

Could this be helpful? https://youtu.be/WjXNsoIIjo4

Wrong engine, sorry. Its my dyslexia...

[SteveSpring]

If the elbow is blocked (which is a common fault on the 2000 series engines) you will need to replace it. A stainless steel version is available from HDI Marine, which isn't much more expensive than the cast iron VP part.

[CruiseEasy]

I have seen guys clean it out with descaler acid for 12-16 hr soak then a small flex snake to break the stubborn stuff loose.

[KWISPEL]

Start the engine and run him 10 second and measure the amount of water in the exhaust in idle RPM.

Remove the fresh water hose after the pump and run the engine 10 seconds and look if the pump is working properly in idle RPM and measure the water.
Do this not to long, otherwise will the exhaust hose become to warm!

If there a big difference is, open the heat exchanger in the back and go in the small pipes with a long metal part like a needle or bicycle spook.
If this not the solution is, remove than the exhaust collector. The problem can be also in front of the heat exchanger, maybe a jam my mussel or barnacle in your intake or in every hose from the salt water system.

This is the way how I did it in the past.

I don’t think that there a anode is if you work with a heat exchanger. In a block with direct cooling is there well a anode. But I can be wrong!

Maybe have other people better ideas?

[deblen]

Link to discussion of VP 200x series exhaust may help you/ Len

Volvo 2003 exhaust elbow removal and replacement. [Archive] - Yachting and Boating World Forums

Explanation of the VP 2003 cooling system,thermostat, & differences between fresh & raw water cooling systems. http://www.ybw.com/forums/showthread...lvo+penta+2003

Exploded view-2000 series engine parts http://www.marinepartsexpress.com/VP_Schematics/

[JasonS]

Lot's of good advice given. I'd second the stainless steel exhaust elbow from HDI marine. We have on both our Volvo Penta D1-30s. Work great, better build than Volvo without the problems.

You may also want to remove your heat exchanger and bring to a radiator shop to have the core cleaned. Volvo may consider the core "sacrificial", but if there is not electrolysis they usually can be cleaned to like new.

But please... first remove your raw water intake hose from the seacock. Open the seacock to ensure you have excellent water flow. Then remove the raw water hose and check it thoroughly to ensure you don't have barnacles. Sounds like you already did the raw water impeller/checked the pump. Then you're into the heat exchanger and elbow.

Good luck!

[Hunky Dory]

I have a friend who has the same engine , his has the glycol heat exchanger. He had water and steam coming out of the exhaust, he too had changed his raw water pump impeller. Had a mechanic check out system and found a partial blockage caused by broken off impeller blades. Removed the pieces and acid cleaned the heat exchanger, problem solved.

[deblen]

Originally Posted by Hunky Dory

I have a friend who has the same engine , his has the glycol heat exchanger. He had water and steam coming out of the exhaust, he too had changed his raw water pump impeller. Had a mechanic check out system and found a partial blockage caused by broken off impeller blades. Removed the pieces and acid cleaned the heat exchanger, problem solved.

This is quite common. The tubes are small. The VP2000 heat exchanger is a b---ch to get at,disassemble & reassemble.
I installed a raw water intake filter between the RW pump output & the heat exchanger input-in addition to the RW filter in the seacock to RW pump input.
Cost me $100,but $$$ in aggravation.
Len

[cjheath]

I had same problem on my VP MD2040D. I checked everything; sea cock, heat exchanger, thermostat, strianer, piping lines... all fine. Eventually i found that the raw water goes through a gearbox cooler on the side of my gear box. it has an anode in there which was completely gone and the cooler ( just a bronze box really) had both inlet and outlet ports blocked with a crusty buildup of some sort. I scraped the crusty crap out of it and the water flow increased dramatically. The engine runs beautifully now and the temperature is stable even under load at about 2800rpm. The gear box cooler was pretty difficult to get to which is probably why it hadn't been serviced by the PO. Good luck.