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Discussion Starter · #1 ·
I have a "new to me", 4 months ago, Volvo Penta 18 hp. It is fresh water cooled with a heat exchanger and anti-freeze circulation. I'm trying to determine if the "zinc plug" on the top front of the engine, about 7/8ish socket, should have a zinc? It doesnt have a fitting on the back. I'm in a higher salinity area than the boat had been for some years. The engine paint looked very good when I got the boat, it had been on the hard for about 4-5 years, but has started to loose paint with about 10 outings and minimal use except for motoring 4 days about 4 hours each. I do have an intermittent very small drip off the bottom of the sea water pump (impeller cover). The self admitted yanmar tech that looked at the engine, to begin with, said it could be a weap hole or leak?? The amount of water and location dont seem in line with the quantity of paint loss and new corrosion. I have new shaft zinc and zinc on both twin keels. Any ideas?
Thanks for any help!
 

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yours zinc should be located on the raw water side of the heat exchanger it self. You should always use a 50-50 solution of anti freeze.. Too much anti freeze can cause electrolysis too. you should probably rebuild your raw water,pump as they are not very expensive if you do it as preventative maintenance. Some pumps, you can turn the cover over to the other side is badly worn. On the inside of the pump is a bridge with a screw holding it in place you should replace it as well as the seal and impeller, be sure to check the bearing and shaft where the seal rides. captg
 

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Discussion Starter · #3 ·
thanks-I'm away from the boat now, but dont see a plug on the diagram or remember seeing one on the heat exchanger?? I'll check again in a few days. the plug I mentioned above is on the anitfreeze side...I know this because I pulled it.
thanks again,
Nathan
 

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I have a Volvo Penta 2003t on my boat. I have inquired before about a zinc on my engine, but have been told there is none. Recently, the oil cooler on my engine failed. The aluminum shell casting corroded through. It appears that the aluminum, bronze, copper, stainless steel and salt water mix provide an ideal galvanic cocktail. Again, no sacrificial zinc. I plan to replace the oil cooler with an after-market model that includes a zinc. Not sure this is what you were looking for, but use it for what it's worth.

I agree with captg's comments regarding the raw water pump leak. It's probably either the front plate (paper) gasket or the rear shaft seal. The screws that secure the front plate tend to be made of some soft metal. So be careful when trying to loosen them.
 

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Discussion Starter · #5 ·
Thanks for you info. I do think the leak is off the front of the pump plate-I have opened it to inspect the impeller, which looked great, last view. Did you lose significant engine paint prior to the oil pump failure?
 

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I have had significant rusting but for another reason. The previous owner never cleaned the vacuum break in the raw water cooling line. Because it was mounted directly above the engine, when it started leaking it dripped all over and everything started rusting. I finally got tired of looking at it, so I took the engine all apart, used a wire wheel to remove the rust, then reprimed and repainted everything. BTW the engine is now gray, not Volvo Green. It looks a lot better.
 

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Can anyone advize how difficult it is to overhaul the raw water pump.I have the overhaul kit just a tad nervous o the bearings etc.Cheers Nigel
 

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I have a "new to me", 4 months ago, Volvo Penta 18 hp. It is fresh water cooled with a heat exchanger and anti-freeze circulation. I'm trying to determine if the "zinc plug" on the top front of the engine, about 7/8ish socket, should have a zinc? It doesn't have a fitting on the back. I have new shaft zinc and zinc on both twin keels. Any ideas?
Thanks for any help!
I have a Westerly Konsort Duo (the motor sailer model), with a VP2003 fresh water cooled engine.

The raw water cooled engine does have a zinc anode. It is at the forward end of the engine, where the pipe for the heat exchanger is fitted on the fresh water cooled engine. There is no zinc anode on the fresh water cooled engine.

I note that you say you have anodes on the bilge keels. If there is no connection to any electrical components on the boat, then the anode is not needed. You DO need an anode on the hull where the engine is connected to the fixing bolts within the hull - usually a pear shaped anode with the big lump facing forward - hydrodynamics. Also, it is prudent to have your shaft anode.

If your seawater pump is leaking, please ensure it is not from the weep-hole just behind the pump. If it is, then your water facing lip seal has failed. Between the water lip seal and the oil lip seal (each facing opposite each other) there should be an o-ring to spin off any leaking water from getting into the engine block.

If the water is coming out of the pump seal plate, you could try fitting a new paper seal before any major repair.

There are two Westerly web sites in the UK, and a Westerly Wiki. See Westerly Owners Association Web Forum, Discussion Group and Westerly Wiki.

Hope to see you posting on our site. ;)

Welcome to Westerly's.

regards,
Philip (Westerly moderator)
 

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I also have a Volvo Penta 2002 built around the same time. It has the nut for the pencil zinc on the top front of the engine and I replace the zinc every 9 months or so. The PO apparently had not been replacing it.
 
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