Opinions wanted: Adding a Raw water intake filter

OldNBold51

Petty Officer 2nd Class
Joined
Apr 19, 2010
Messages
169
I've been thinking about adding a raw water intake filter to my 7.4L engine this winter. What are the pros and cons and where can I find a decent filter? How should I mount it and what are the pitfalls to look out for?
 

bruceb58

Supreme Mariner
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Mar 5, 2006
Messages
30,581
Re: Opinions wanted: Adding a Raw water intake filter

Why would you want to do this? What kind of water do you typically boat in? You have an inboard or an outdrive?
 

familyguy

Seaman
Joined
May 30, 2008
Messages
69
Re: Opinions wanted: Adding a Raw water intake filter

Unless you have a really good reason this would be a mistake. The water intake and passage ways through your lower unit, raw water pump, engine, thermostat housing, and manifolds are already small enough to cause problems. Why add to the risk of overheating your engine by putting in a filter. If you run that boat shallow in overgrown, weeded water you would be accessing that filter to clean it more than you would be boating. Find another body of water if that's the case, or convert to closed cooling system (expensive).
 

Bondo

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Apr 17, 2002
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71,079
Re: Opinions wanted: Adding a Raw water intake filter

What are the pros and cons

Ayuh,... I can think of Any pros,.... None....

as for cons,... The filter plugs up, then your motor overheats,... Then you get to buy a new motor....
 

OldNBold51

Petty Officer 2nd Class
Joined
Apr 19, 2010
Messages
169
Re: Opinions wanted: Adding a Raw water intake filter

The water I boat in is some of the cleanest freshwater in the states but recently we had a flood which left quite a bit of flotsam in the water.
A friends boat clogged up the screen in the oil/power steering cooler and overheated badly.

I was just trying to avoid what happened to him.

It sounds like there is not a good reason to have a filter installed.
 

f_inscreenname

Commander
Joined
Aug 23, 2001
Messages
2,591
Re: Opinions wanted: Adding a Raw water intake filter

We use sea strainers in the raceboat but they cost some money (even for used) and take a little to get installed. Any type of paper filter type will clog way to soon.
87800664.jpg


With that said I don't use sea strainers in the other two boats. No reason.
 

Bluestream

Petty Officer 1st Class
Joined
Sep 28, 2010
Messages
296
Re: Opinions wanted: Adding a Raw water intake filter

The water I boat in is some of the cleanest freshwater in the states but recently we had a flood which left quite a bit of flotsam in the water.
A friends boat clogged up the screen in the oil/power steering cooler and overheated badly.

I was just trying to avoid what happened to him.

It sounds like there is not a good reason to have a filter installed.

If the water clogged his screen, what do you think it will do to a filter?
 

kilowatts

Petty Officer 1st Class
Joined
Apr 3, 2009
Messages
299
Re: Opinions wanted: Adding a Raw water intake filter

Hi Guys:

I had a raw water filter on a single cylinder 4HP BMW diesel engine similar to the previous photograph. It was very easy to clean and had a screen which I would wash out after each trip. If I'd been boating in a weedy area I had all kinds of weed bits in the screen which would otherwise have been in the engine! Never had any sand though. I guess I'd vote for the screen type filter.

kilowatts
 

telstar1

Petty Officer 1st Class
Joined
Jun 20, 2008
Messages
226
Re: Opinions wanted: Adding a Raw water intake filter

Diesel Volvos have a raw water filter. Works well, the filter basket would need cleaning maybe every 20 hours in West Coast Canada saltwater conditions. I ran one for 25 plus years for my employer and in the same time period ran a Mercruiser for pleasure, similar hours on each. Merc of course had no filter. If anything we had more overheat issues with the Volvo. The filter seems like a good idea and Ive actually owned one(want it?) ready to install on my m/c for years, but the evidence from my perspective seems to say forget it.
 
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