Tohatsu 2.5A cooling water stuck at ZERO

[whitegreg56]

So, last Fall, I ran it for 10 minutes in fresh water, ran it out of gas, drained the gear oil, and storage sealed the cylinder.
This Spring, I replaced the spark plug and refilled the gear oil...expected all would be good.

I started it up...it runs like a dream but there is absolutely no cooling water flow.
I tried some compressed air backwards through the outlet tube (that has worked in the past when the flow is poor) ...NOTHING.
I ran a wire up the outlet tube...NOTHING.
I filled a plastic syringe with water and put the tip into the outlet tube and put pressure on the plunger...NOTHING.

Where do I start with this?
Separate the lower unit?
Access the water pump impeller (it is on the propeller shaft)?
Remove the cylinder cap and clean the passages?

I don't want to do any more work than I have to in order to resolve this!

 

[tohatsu_guru]

Is The engine actually getting hot or are you just not seeing water flow out the Pee tube or behind the engine?

 

[whitegreg56]

The underside of the cylinder is definitely getting hot.
There is a tiny bit of moisture coming out of the little holes in the back of the driveshaft housing.
I would NOT call it a spray at all.

When I put pressure on the water-filled syringe plunger, it doesn't move at all...rock hard!
I am guessing salt/aluminum is totally blocking the passage...the question is "where"?

 

[whitegreg56]

Here's the syringe...press fit.

 

[whitegreg56]

Well, I decided to dig in a little deeper.
I managed to separate the gear case from the driveshaft housing and
the cover over the propeller-shaft impeller without breaking any bolts.
Used plenty of penetrant and rocking back and forth with the ratchet drive.

The water passage in the gear case looks unobstructed and I ran a stainless wire up the water tube
inside the drive-shaft housing.

Still no movement of the plunger in the syringe when pressure is applied.
So, next move (I guess) is to take the cylinder cap off....
Stay tuned!!

 

[whitegreg56]

Well, I decided to dig deeper, again.
I managed to get all four cylinder cap bolts out
without breaking any of them.
Photos of the cylinder cap and cylinder with gasket in place are attached. Yuk!

The water passage in the cap is totally plugged
with salt and sand. When I took the gasket off
the cylinder, I found the water jacket loaded with
salt and sand. I took out maybe an eighth of a cup of the stuff with a small screwdriver.

Now, when I put pressure on the syringe on the
outlet tube, we get good flow. Hope this thread
may help someone else with the same problem.

The cylinder cap gasket is on "national backorder"...whatever that means. I found
one on ebay...should be here this week.

Just need to reassemble and verify good flow!