Freshwater flushing outboards while cruising, practicallity?

[Franziska]

Hi,

I'm wondering how other folks with just outboards on a cruising sailboat handle this.

Manufacturers suggest to always flush your engines after seawater use.
Be it main engines like our twin 9.9 or the dinghy outboard.

On a cruising sailboat with limited freshwater supplies that seems rather impractical.

So far we hardly do it, but we are currently looking into using a 10l canister with a pump to recirculate flushing water and using it several times.
How practical is it to flush the engine when folded up?

I'm talking not about huge boats with almost unlimited freshwater supplies or folks mostly going into marinas or dockside.
Primarily I'm asking folks who prefer anchoring.

[Rumrace]

Some of the big outboards have Merc Cathode which sure helps. Little outboards get neglected. I think flushing it as often as you could is best.

[Cheechako]

For a boat that will sit some time between uses it is very important. For a boat run daily or every other day not a big deal.
BUT I would say that for small outboards that I used only very occasionally, 50-75% of the time on restart there will be no cooling water flow from impacted salt in the exit tube if not fresh water flushed.
I have even bought two used outboards at bargain price that were sold as is "needing a new water impellor in the drive" according to the seller. Neither needed anything other than cleaning out the exit tube passages.

[wingssail]

Originally Posted by Franziska

Hi,

I'm wondering how other folks with just outboards on a cruising sailboat handle this.

Manufacturers suggest to always flush your engines after seawater use.
Be it main engines like our twin 9.9 or the dinghy outboard.

On a cruising sailboat with limited freshwater supplies that seems rather impractical.

So far we hardly do it, but we are currently looking into using a 10l canister with a pump to recirculate flushing water and using it several times.
How practical is it to flush the engine when folded up?

I'm talking not about huge boats with almost unlimited freshwater supplies or folks mostly going into marinas or dockside.
Primarily I'm asking folks who prefer anchoring.

We use our 15hp Merc while cruising which means anchored out. This motor is a 2000 model so it is 22years old. I have never flushed it out (nor have I run the carb dry when putting the motor away or changed the water pump impellor. I do change the lower unit oil periodically, and I changed spark plugs once. That's about the only maintenance I do). The motor has been immersed in salt water three times, twice when running. It still runs fine, runs a LOT of water out the cooling system, and gives us very little trouble.

[thomm225]

I try to flush my 5 hp outboard which is also my Bristol 27's main engine with salt water at least once every few days to every two weeks during the Winter.

Once a year when I change the oil(s) I back the boat into my slip and give the outboard it's yearly fresh water flush.

As a young person, I never saw a waterman flush his outboard at the end of the day.......

[CarlF]

In 55 years of owning outboards used in salt water (and 25 years with an outboard dinghy on a cruising sailboat) I’ve never flushed one and never had any problems. Give them fresh gas (preferably without ethanol).

And I never see commercial fishermen who’s outboards are in the water 365 days a year flush their outboards

Be sure to tilt them and replace the zincs as needed.

[JPA Cate]

Franziska,

Our story is similar. The only time it gets a good freshwater treatment is when there has been a lot of rainfall, or we're going up a river that goes fresh. However, ours have all been 2 stroke engines.

Ann

[Chotu]

i’m another one. Decades and decades without flushing any outboards. It just doesn’t seem to be an issue. Just make sure you replace any zinks when they are due.

And of course keeping the lower unit out of the water is better than in.

Other than that, I’ve never had a problem

[Franziska]

Guess that settles this issue [emoji4]

Thanks everyone!

[thomm225]

There is one guy though at my marina that sails a small 25' sailboat with a newish 9.9 Mercury on a bracket.

He flushes his outboard with fresh water for maybe 5 minutes after every sail.

He sails single handed.

It seems to take him about the same amount of time to get his boat backed into his slip to complete this task, but he does it each time without fail

[Chotu]

Originally Posted by thomm225

There is one guy though at my marina that sails a small 25' sailboat with a newish 9.9 Mercury on a bracket.

He flushes his outboard with fresh water for maybe 5 minutes after every sail.

He sails single handed.

It seems to take him about the same amount of time to get his boat backed into his slip to complete this task, but he does it each time without fail

Thomm:. She's asking about cruising, which means you don't have ready access to fresh water. Just whatever you are carrying in your tamks or making from a watermaker. Not living on land and keeping her boat at a marina.

Cruising presents different constraints, of course.

[smj]

If you aren’t able to freshwater flush it’s important to run your outboard often enough to keep the saltwater from crystallizing inside your cooling system. A mechanic told me to try to bring the outboards up to temperature once a week if possible. I do try to freshwater flush before storing the outboard for any prolonged period.

[Captain Bill]

Some brands are more prone to having problems with saltwater than others. The 9.9/15/20 hp series from Suzuki is notorious for having the powerhead clog with corrosion after a couple of years. In my case it was three years. You can find a couple of threads discussing the issue on this forum. I never had an issue with not flushing my old Yamaha, but that had other issues. I am now trying Tohatsu, but since it is less than a year old I can't say if it will be a problem yet.

[smj]

Originally Posted by Captain Bill

Some brands are more prone to having problems with saltwater than others. The 9.9/15/20 hp series from Suzuki is notorious for having the powerhead clog with corrosion after a couple of years. In my case it was three years. You can find a couple of threads discussing the issue on this forum. I never had an issue with not flushing my old Yamaha, but that had other issues. I am now trying Tohatsu, but since it is less than a year old I can't say if it will be a problem yet.

I bought a used Honda 9.9 and a catamaran with a Honda 15 installed, both had clogged power heads from corrosion.

[thomm225]

Originally Posted by Chotu

Thomm:. She's asking about cruising, which means you don't have ready access to fresh water. Just whatever you are carrying in your tamks or making from a watermaker. Not living on land and keeping her boat at a marina.

Cruising presents different constraints, of course.

It's easier on your outboard when you are cruising because you are using it.

Well some of us are.

I have a kayak so to get to land I deploy the kayak and paddle which gives me at least some exercise.

My outboard is the main auxiliary engine for my boat so it get lots of use and is flushed with salt water every 2-4 days during the season and once every week or two in Winter

Also it's pretty obvious your average cruiser wouldn't flush their outboards very often unless they had a huge boat with dingy or runabout storage onboard