Raw Water Filter

[ElmaBay]

I just recently purchased a San Juan 30 with an Atomic 4 at the helm. Upon inspection of the engine set-up, I noticed there was no filter for the raw water. This motor does not have fresh water cooling so all the bits and pieces of the great blue ocean are ending up circulating and I suspect depositing atleast to some degree within the engine cavities. My question to the A4 Forum, then is; "Should this cooling system be enhanced with a raw water filter? "

Furthermore, would it be beneficial to install a fresh water cooling system on an older engine (1976) that has never had such good fortune and has for most of it's life been subjected to salt water. The boat has had two previous owners. One raced the boat and only used the engine for coming and going. The last owner who had the boat for two years kept it docked in fresh water and for much of the time, only worked on the boat restoring it at the wharf. The joys of boat ownership! In summary, I don't think the engine has many hours on it, although this can not be confirmed. For the record, the engine runs like a gem.

Any suggestions?

[rigspelt]

Good questions. Here are my amateur thoughts.

Should this cooling system be enhanced with a raw water filter?"

I wouldn't be without one. Overheating from coolant flow jams are not fun.

Furthermore, would it be beneficial to install a fresh water cooling system on an older engine (1976) that has never had such good fortune and has for most of it's life been subjected to salt water.

I researched this last year when I started out with an A4 for the first time, and the balance of opinion in the archive seems to be yes, it is unlikely to be too late to add FWC if the engine is sound. Our previous boat had FWC. Our 1974 A4 had been in freshwater for 25 years and then salt, so it had a big leg up, but I don't regret adding FWC. It costs money, the pre-installation flushing and kit installation takes time, and there are a lot more hoses cluttering my engine space, but for me it's worth the piece of mind. In our case, I spent time ensuring the engine was sound prior to investing. Try searching the forum archive to get a feel for the arguments.

[rheaton]

I just finished this task on my 1978 Catalina 30. I needed to relocate my batteries from the engine compartment. I also needed to cut a new access hole in my engine compartment in order to install the pully on the front of the engine. Installation of the actual unit components was not very difficult or time consuming.

I do say the work was enjoyable and satisfying. I learned a lot of things as well. Don and the nice folks at this site will advise you on every step of the way.

Best of luck to you.

Take care,
Russ

[Marian Claire]

Defiantly yes to the raw water filter. Much easier to clean than any other part of the cooling system. At least on the MC. Dan S/V Marian Claire

[ElmaBay]

Thanks for the info. Very useful. Time to open my wallet again.

[67c&ccorv]

Just finished installing a Groco 750 raw water filter on Dulcinea - she has spent her 40+ years on the Great Lakes and this is relected on the state of the interior of the engine water cooling passages.

A clogged raw water inlet could have disasterous consequences for engine cooling, hence my installation of the raw water filter and Moyer water temperature and oil pressure alarm system.

[Mark S]

When I cleaned out the raw water filter last fall I was amazed at the crap that had accumulated and relieved that it hadn't gotten into the engine. As to adding FWC, my engine dates from 1980, or so the legend has it, and has always been RWC in salt water and is still going strong. Others will disagree, but I see no reason to spend a lot of money for FWC when RWC works fine.

Mark S

[Dave O]

I sail in Lake Ontario (Port Credit) and I'm frequently surprised by the amount of "junk" on the surface of the water. I only hope that what I see on the surface is not what is flowing through the water intake.

I have made a number of upgrades to the engine and a raw water filter (Groco 3/4") will be my next addition over the summer.

I agree it's a lot easier and cheaper to prevent than to cure. A comparatively simple addition like this makes sense.


Dave O
C&C 29 Mark I
Port Credit, ON.

[67c&ccorv]

Here is a pic of the Groco 750 raw water filter installed in "Dulcinea" - a 1967 C&C "Corvette". (Not much room in there and I had to shorten the gunk drawer to 14" to make everything fit!)

[dvd]

My 1974 Cal 3-30 has a raw water filter of some kind. Its a round thing that has a clear plexiglass top so you can see into it without opening it. The clear plexiglass top has a hole in the middle of it.A threaded stud sticks through this and is held down by a plastic knob that screws down tight. The metal filter screen inside this thing has fairly large holes that only traps larger things like whole pieces of hydrilla and other various sea weeds. I have cleaned it several times and I think it is necessary considering what I've found in there.

DVD

[ElmaBay]

Here is a pic of the Groco 750 raw water filter installed in "Dulcinea" - a 1967 C&C "Corvette". (Not much room in there and I had to shorten the gunk drawer to 14" to make everything fit!)

I picked up a Groco 750 last weekend, but have yet to install it. I noticed there is a screw to attach a wire to for grounding. Is this necessary? Not a big deal, I was just wondering.

[rigspelt]

Here's my new Groco 750 installation. Started the engine today in the ocean for a few minues today for the first time and it caught a large jellyfish. Probably wouldn't have caused any difficulties with the waterpump or exhaust, but it sure was easy clearing the mess from this filter. Significant object lesson for me: glad I replaced that tiny, hard to reach plastic filter at the last minute last week before splashdown.

[ElmaBay]

Nice catch!

[P30_889]

Raw water filter (in the Chesapeake Bay)

For the past 10 years I have sailed my boat in the Annapolis area (9 more years of sailing other people's boats) and while I agree in principal about getting a raw water filter, I have to say that when I had one (on my first P30) I NEVER had to clean anything out of it. Currently I do not have anything on my intake. I do plan on installing something but so far I have been lucky. Granted - the bay is very brackish so we don't have much floating around in the bay except dead Rock fish!

[tenders]

I've never caught anything interesting or sizable in my Groco raw water strainer either, except a few tiny shrimp who wouldn't have given anyone any trouble getting blown through the engine.

Once, before I had the strainer, a plastic bag got sucked into the intake and lodged in the hose before it would have been caught by the strainer. Took a while to troubleshoot but the strainer wouldn't have helped.

I still wouldn't be without one, though.