Yam 15hp advice part 2 - urgent!

[Max...]

Sorry chaps but in a pickle now, due out first thing tomorrow, any help really appreciated - been servicing the 15 Yam 2 stroke this afternoon, usual stuff, oil, plugs, greasing etc.

Finally came to test - in a water tub, level just over the cav plate.

Seems to be a pump problem - water spurts out of the tell take like nothing else, but after 5 mins warm up there is a small continous (farty) spurt from each side of the leg (the two small holes at the base of the leg just above the cav plate) and what comes out is very hot. There is nothing from the two larger holes at the top of the leg under the main engine - but I can feel exhaust (?) or air being pumped out - I was presuming the main cooling water flow should come out of here as with a Tohatsu.

Main thing is the whole leg is *hot* just after 5 mins + on idle.

Only other thing is the tell tale end plug is larger than normal - previous owner complained it was getting blocked too easily...

[Nick Hearne]

Max have you got a photo to show what you mean?
The leg dose get worm as the hot exhaust gasses are passing throw it.
Nick

[Max...]

Hi Nick, no pic but two small holes above cav plate (underside of leg) spurt out v. hot water (a spit not real flow) - the two larger holes at top of leg (under cowl) spurt out air/exhaust (no water) - are they supposed to?? Leg to my mind is *really* hot wheras my Tohatsu gets mildly tepid and water comes out of the same top holes....

Edit - pic added. *Not quite accurate - the two holes I'm expecting water to exit at top are by the 'a' in air not where the arrows are.

[PeterM]

Sounds sort of OK to me ...Water will run out of the exhaust ( through ) prop hub and thinking maybe the 'hot hot ' water out of the 2 holes is just due the leg not being cooled by any water passing over the leg as it would if moving ? More revs = more water flow = more cooling ?

Most of the OB I ever used or owned run cooler when revved a bit due to more volume of water being moved about ....

I think I had a suzuki that only ever had water out of the top holes when revved hard - and the holes vented exhaust when slow/idle ?

[Nick Hearne]

Are you getting exhaust coming out of the?

[Max...]

Just seemed odd the leg should get that hot after such a short idle, impeller and 'stat were changed last season and telltale is superb. Maybe it's me but I just thought water would come out top somewhere apart from all through the prop.

The Tohatsu has exactly the same two small holes at base of leg and larger outlet at top with a constant flow at idle.

Nick - out of the...?

Peter (B&O) - you've had a few of these I guess - do you recall or have a vid anywhere?!

[Nick Hearne]

Originally Posted by Nick Hearne

Are you getting exhaust coming out of the?

Don't know what happened there I was ment to ask is the exhaust coming through the prop?

[Max...]

Yes, certainly seems to be.