1995 T9.9 ELHT outboard water coolant blockage

[MacGregor26D]

hello and thanks for any responses. I bought a sailboat with a 9.9 ELHT motor. No water flow through the tell tale. I used the impeller kit and replaced all parts. Still no water at tell tale. Blew air through the system on both sides of the thermostat. I removed the thermostat. Air went through the engine fine but very slow through the water tube from lower unit attachment. Could there be some kind of clog in the space where the tube attaches? The tube is clear I removed it to check. So to check if the impeller is working which way should I turn the drive shaft?
Thanks again for any help.

[DennisG01]

Is water coming out the exhaust?

Are you running the engine on a hose or in water/tub?

[panasonic]

Run the engine with muffs and see if you are getting water out the exhaust...as already noted.

You say you changed the WP because it was not putting water out the tell tale in the first place? Or since you changed the WP it does not pee?

Was the old pump impeller still in tact when you removed it? If it had gone to pieces you may have bits of rubber gone up in the block.

[MacGregor26D]

Thanks guys- I ran it on muffs with a hose. Even held the muffs tight with my hands. There wasn’t water coming out of tell tale before I changed the impeller. The existing impeller was intact. T

[rodbolt17]

has this engine been used in saltwater?
if so I can tell you the issue and a solution.

[MacGregor26D]

Yes I pulled the thermostat and it appears I have water flow on both sides. I may of turned the drive shaft counter clockwise a little to line the splines up when reinstalling the lower unit. I’ll check. Yes I think this engine was used in salt water based on the condition of the thermostat and the inside of the crankcase.

[MacGregor26D]

Water flow meaning from the top down. It’s a lot of pressure to get a little water from the copper tube that connects the water pump. The copper tube is clear. up into the

[MacGregor26D]

Thanks Scott! I am not a stranger to stupidly simple.😊I’m going over all the hoses as suggested . And hoping RB can offer a solution otherwise. Glad I found this place.

[MacGregor26D]

None taken whatsoever, thanks again 👍🏽

[99yam40]

I had an old 35 hp Evnrude that the grommet where the water tube up into the power head pinched off /restricted due to corrosion squeezing it I guess.
I never did pull the power head, just sharpened a rod and cut some notches in it and used that to open it up some. it ran and cooled OK for many years.
I think it was a straight shot up to it thru the water tube from what I can remember, but was a very long time ago. I cannot be sure what all I had to do.

It will be interesting as to what Rod says the problem could be
could be salt building up due to not being flushed with fresh water very often out sailing and no access to the water to do it

[MacGregor26D]

Great idea. I ran a 12 gauge wire up the tube before I realized I could remove the tube. I’ll try a straight rod from the grommet at the power train up into the head. I don’t see another way to access that area without major mechanical efforts. It seems to be the area of the clogg though. Would flushing from top down with a salt break down solution work?

[99yam40]

It would be best to look up there 1st to see what you can see.
bore scope lighted camera would help a lot so you know what you are dealing with

need to know what is in the way before you can figure out how to remedy it

[rodbolt17]

2 remedy's.1 pull the head and ex cover and clear it.
2 pull the cam cover, drill the two passage plugs and tap them 1/4x20. use a bolt,nut and washer and pull the plugs.
the passages between the ex and the 90* nipples are clogged.
I keep spare plugs that a local machine shop makes in my tool box.

[rodbolt17]

part 24 is the nipple.
it is replacable but it is not the problem.
the problem is the passage between that nipple and the block.
it requires head or plug removal and ex cover removal to clear the passage.
I have done enough that I keep spare plugs.
plugs are NOT available from Yamaha.

[MacGregor26D]

Thanks for the replies. Rod- what is the ex cover you mentioned to remove? I’d rather not pull the head every time there is a clog. It doesn’t seem as simple a fix as I thought Lol.