Tohatsu Engine Rinse

emarshbuck

Seaman
Joined
Dec 2, 2015
Messages
70
I'm getting conflicting advice on how to rinse out my 25HP Tohatsu engine after pulling it out of salt water. When I first bought the boat I was using the rubber paddles on the bottom of the motor. Then my local dealer sold me the garden hose attachment for the engine block.

So, what's the best way to rinse out the salt water? Dealer says to hook up the garden hose, run the engine for 3-4 minutes. Neighbor who was marine commander for Lee County, FL, sherriff's office, says to use the paddles while running the engine. Another guy says running the engine while rinsing causes the thermostat to close thereby not allowing the fresh water to flow through the cooling system.

thoughts, suggestions?

thanks to all.....
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Assume that rubber paddles is a wording for muffs, right ?

Having a 30 HP which is the elder brother of the 25 would say that the best flushing method after use with fresh water is with muffs. For that will need to count with adequate water pressure at your facility. If engine has a extra water intake strainer under lower AV plate, tape it before putting muffs on to increase water pressure.

Using the flushing port it's OK, the only down issue is that if will be removing bolt constantly may end damaging the engine's threads in the long run, which is no bueno.

For a correct flushing engine must be running ON at idle or fast idle, geared if you like, just watch out for a spinning prop. With engine ON, thermo will open and flush the cylinder head area, that doesn't happen with engine OFF.

Run engine for at least 5 minutes, disconnect fuel hose from engine and let die of fuel starvation, will keep the internal carb dry and clean.

Happy Boating
 
Last edited:

pvanv

Admiral
Joined
Apr 20, 2008
Messages
6,500
First, we need to identify your model (not year) to determine which motor you have. Next, understand that you want to flush the head as well as the rest of the passages, so running is needed. Lastly, as Luis noted, you need to make sure you have enough water. Muffs is OK, but if there is a sub strainer, you need to tape that off, or most of the water will escape. The MFS25C has a garden hose connector for flushing. Follow the owners manual.
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Flushing Port vs Muffs Comparison :

-If using the powerhead's flushing port will need to constantly: remove cowl, remove flushing bolt, install water hose and adapter, flush, unscrew hose, screw back bolt, put back cowl. Imagine all that being done on a constantly basis if will be boating frequently.

-If using the lower leg flushing port, will need to tape both side water intakes and 1 lower water strainer undel AV plate, if not, there will be scarse water flow for water pump to do its homework right. Add remove lower bolt, screw adapter and hose, flush and so on...

For me ear muffs all the way and if modified from factory much better, with adequate water pressure assures minimun water loss at muff's side. Pics speaks for themselve..

Center well ear muffs on middle lower water intakes, glue epoxy belt retainers :

Belt Retainer.JPG

Attach a belt and tighten it hard against retainers or roll up several rounds of rope around them, once tied leave them there for next flush.

Muffs & Belt.JPG

Flush engine ON at idle-fast idle, geared if you like as long as you want, disconnect engine's fuel connector and let die of fuel starvation and voila!! This method is way faster, saves time and flushing hassle.

Muff Flushing.JPG

It's your call which flushing method suits you well...

Happy Boating
 

emarshbuck

Seaman
Joined
Dec 2, 2015
Messages
70
Ear muffs are my future! It was a labor intensive process using the engine hose port. And thanks for the suggestion about letting engine run dry....I've had issues last year with carb gunk, even though I use marine gas and stabil.

And for clarification, you're saying once I've tightened down on the muffs with some type of belt/rope system, leave the belt on the muffs. But I do need to remove muffs off inlets, yes? I know, sounds obvious, but you never know with an apprentice seaman. See you on the water!
 

Attachments

  • photo302767.jpg
    photo302767.jpg
    143.2 KB · Views: 1

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Yep, self added once you have middle muffs well centered on middle intake screens. If left plain as factory deliverd belt will tend to slip off and lose best water pressure around muffs.

Click image for larger version  Name:	03.JPG Views:	1 Size:	196.1 KB ID:	10672259

Happy Boating
 

Attachments

  • 03.JPG
    03.JPG
    196.1 KB · Views: 0
Last edited:
Top