Engine corrosion

[Clay Greene]

I am attaching a photo of corrosion and what looks like a hole in what I believe to be the water pump of a M35B engine in a 2004 Mark II boat I saw this weekend.  The boat was sailed in salt water until 2009 and it has sat on the hard since then.  Anyone have any theories on what could cause this extent of corrosion?  What would be the implications for the rest of the engine?  The engine meter shows 221 hours. 

[Clay Greene]

Here also is a photo of the bracket to which the transmission cable attaches.  We're freshwater sailors so any amount of corrosion is a concern to us but this amount seems extreme for a boat sailed in salt water. 

[Clay Greene]

Here is one more, a photo of the transmission coupling and the prop shaft.  You can also see a suspicious dark line from the butterfly valve on the muffler. 

[Clay Greene]

Sorry, one last photo, this one of what I believe to be the bottom of the heat exchanger and the aft engine mount on the starboard side.  You can almost see the green flakes falling. 

[Tom Soko]

Claygr,
The first photo shows a Sherwood raw water pump which needs its seals replaced.  The body of the pump is mild steel (not the most brilliant design, IMHO) and rusts quickly.  Not a big deal, but it should be looked after.  If ignored, you could rust out the oil pan.  Photos 2 and 3 show the results of spray/mist from the packing gland (not the drain on the aqualift muffler).  It should be adjusted and/or replaced with Goretex (GFO) packing.  The black streak will clean up easily, and the aft end of the shift bracket can be wire-brushed and re-painted.  Again, no big deal.  The last photo shows the aft port motor mount, which is under the zinc in the heat exchanger for most Universals.  It would be normal to have some corrosion in that spot, showing that the zinc has been replaced and not ignored.  Wire brush and paint.  

[scotty]

Is this a boat you're thinking of buying?  Engines don't do well when they just sit.  Did you get to run the engine?  A good hard poke with an awl can tell if corrosion goes deep into various surface parts.  I've seen corrosion similar to this on a lot of salt water boats.  After two years sitting, a good look by a mechanic would be appropriate.  Oil analysis is a good idea too.

[Clay Greene]

Yes, we are considering buying.  And I agree about the engine survey (particularly after I have seen the engine).  We did not have the opportunity to run the engine. 

[Stu Jackson]

I wish you all the luck, and you can be among a fine group of C34 owners who have bought their SECOND C34!  Good choice.

[Stewartn]

I would immediately remove and re-build or replace the Sherwood raw water pump. The corrosion could and did block the weep holes in the pump. This resulted in letting sea water into the engine. About $10,000 later we had the boat back in the water. Trust me, replace the pump now. Westerbeke was adamant about it was something "I shoulda', coulda', wooda'" taken care of during normal maintenance. My new Sherwood, installed in 2009, will be replaced 2014 no matter what. Good luck.

[Stu Jackson]

There's a post on the Critical Upgrades topic about just this issue.

And this recent topic:  http://c34.org/bbs/index.php/topic,6151.0.html

[Ron Hill]

Clay : One of the problems is that water/especially salt water on unprotected (unpainted) metal will really show up.  (It's hard to tell sometimes if the damage is superficial or deeper until it's cleaned up.)  Salt water rust is difficult to neutralize, clean and repaint.  It will take some elbow grease, but it can be painted after it's cleaned up. 

Tom has the analysis correct.   A few thoughts.

[Clay Greene]

Thank you all.  As I said, we've always sailed in freshwater so this amount of corrosion is unusual to us.  The owner is having a mechanic evaluate the raw water pump.  I will be interested to hear what he has to say. 

[John Langford]

"My new Sherwood, installed in 2009, will be replaced 2014 no matter what"

Good luck waiting that long. I replaced my old leaking Sherwood in 2008 and I noticed the other day that it has begun to weep already. In 2008 I was able to buy a new Sherwood for around $240 which wasn't much more than the price of reconditioning the old one (not including a new shaft). These days the lowest price I can find for a new pump is over $430 at Fairfield Supply. The major repair kit will run to $220 (plus another $100 for a shaft if you need it) before you do or pay someone else to do the work. What a rip-off!

I am looking seriously at going the Oberdorfer route even though it requires a fair amount of adaptation of the Oberdorfer pump. It appears to sell for about $250.

[Joe Kern]

Does anyone happen to know offhand the type/color of paint on the engine in the picture below?   

[Ron Hill]

Joe : My exact info is on the boat, but if you go to PEP Boys there is a light metallic blue that's almost the same.

The can of touch-up is slightly more blue, but is MUCH cheaper that Westsrbeke.