Flushing adaptor for Tohatsu/Mercury/Mariner motors
Posted: Dec 29th, '20, 21:27
The Tohatsu MFS6C SailPro has a flushing port on the underside of the motor pan at the rear; it's the 13mm hex head (eg: 13mm or 1/2" AF spanner) M8x1.25 thread plug between the 10mm hex head bolts holding the motor into the pan. Most if not all Tohatsu/Mercury/Mariner small outboards including 2 strokes appear to have the same flushing port.
The Tohatsu part number for the adapter is 336-60007-0; the Mercury/Quicksilver part number for the same part is 16841Q02:
. They are made for a 5/8" ID hose, which appears to be the standard size for garden hose in North America, but which isn't dreadfully useful here in 1/2" / 12mm Australia! They're also expensive.
The threaded end is not BSP nor NPT, as an engineer would expect; it's M8x1.25
Today I bought three sets of M8x1.25 male to 1/4" BSP female and 1/4" BSP male to 1/2" hose barb from Enzed (a national hydraulic component supplier) in Moorabbin for just under $30 total; $9.90 each set. I could also have bought 1/4"BSP male to female 90degree elbows, but it didn't occur to me.
One set is destined for Jim's Tohatsu Sailpro at Wyndham harbour, another is destined for Adrians Tohatsu 4 stroke 9.8 short shaft in the bowels of his Noelex (not an easy job to extract it!).
The instructions in the manual for the SailPro say to only run the motor at idle, elsewhere instructions say not to run the motor at all, as the water is supplied above (after) the water pump, so it's not a replacement for a drum for tuning, etc, but it is an easy fresh water flush with a garden hose. Because it is after the pump, there should be positive pressure when running, so a short hose with a female click-fit hose fitting with a valve should prevent water leaking out and allow the adapter to be left in place. We'll report back when we have tested this!
If you buy the same parts, use teflon tape between the two parts and between the brass and the aluminium motor, and fit a fibre washer at the motor. This will:
The Tohatsu part number for the adapter is 336-60007-0; the Mercury/Quicksilver part number for the same part is 16841Q02:
. They are made for a 5/8" ID hose, which appears to be the standard size for garden hose in North America, but which isn't dreadfully useful here in 1/2" / 12mm Australia! They're also expensive.
The threaded end is not BSP nor NPT, as an engineer would expect; it's M8x1.25
Today I bought three sets of M8x1.25 male to 1/4" BSP female and 1/4" BSP male to 1/2" hose barb from Enzed (a national hydraulic component supplier) in Moorabbin for just under $30 total; $9.90 each set. I could also have bought 1/4"BSP male to female 90degree elbows, but it didn't occur to me.
One set is destined for Jim's Tohatsu Sailpro at Wyndham harbour, another is destined for Adrians Tohatsu 4 stroke 9.8 short shaft in the bowels of his Noelex (not an easy job to extract it!).
The instructions in the manual for the SailPro say to only run the motor at idle, elsewhere instructions say not to run the motor at all, as the water is supplied above (after) the water pump, so it's not a replacement for a drum for tuning, etc, but it is an easy fresh water flush with a garden hose. Because it is after the pump, there should be positive pressure when running, so a short hose with a female click-fit hose fitting with a valve should prevent water leaking out and allow the adapter to be left in place. We'll report back when we have tested this!
If you buy the same parts, use teflon tape between the two parts and between the brass and the aluminium motor, and fit a fibre washer at the motor. This will:
- Seal the joins
- Protect against electrolysis
- If you manage to break anything, ensure the broken thread left in the motor comes out easily with an Ezi-out!