2001 Yamaha 90 hp 3cyl 2 stroke spitting water

[Rlilleaas]

Hi,

My 90 hp Yamaha has started to spit out water from underneath the engine. it is literally pissing out. Has anyone else experienced this? My local Yamaha dealer had no experience with this but advised me to pull the head. The motor is used in salt water, obviously corrosion could be an issue

Can anything be blocked? Any advise other than pulling the head and see?


While running the engine on dry land using "ear muffs" no leak was discovered - this could possibly be caused by lower pressure from the water hose than the impeller can generate when at sea.

Experience from other users/pictures is much appreciated.

[TownsendsFJR1300]

Don't pull the head...

Pull the top cowl, put in the water and look for water gushing.

As I re-call reading here, it's likely a combination of corrosion and gasket failure between the powerhead and mid section unit. (See below link)

Someone else will chime in with more, detailed info...

Also, please post a complete MODEL #


http://www.boats.net/parts/search/Ya...ING/parts.html





.

[Rlilleaas]

Thank you for your reply,

I meant pulling the motor, not only the cylinder head.

The engine is a: Yamaha 90AETO

I could not see any water coming "upwards" with the "engine cover" off, assume that's what you mean by top cowl?

Assume no seal/corrotion can be repaired without removing the motor from the upper casing?

Best regards
Roar

[TownsendsFJR1300]

I initially meant inspecting with the engine open, the COVER OFF.

But yes, looks like the power head (not the head) will likely have to be separated from the mid section. If there's corrosion there, depending on where exactly, you can very likely fix it with "JB weld" or have it heli-arced.

If your pretty mechanically inclined, have a shop manual, decent tools, you should be able to remove the power head yourself...

As much water that's coming out of there, it shouldn't be hard to find...

Again, someone else may chime in with roughly/exactly if there's a usual failure point would be...

You really don't want to run the engine (on an outing) as your sooner or later going to over heat loosing that much water...

[Rlilleaas]

Does anyone have a picture from the manual of which bolts (and how many) to be removed to pull the powerhead?

Does it help to remove the lower unit first, or is this not required? (thinking of the driveshaft)

Thanks,

mvh
Roar

[TownsendsFJR1300]

If your in the USA, there's 3 models: TJRZ, TLRZ or C90TLRZ.

In any case, click on the parts fisch below, zoom in and then look at the # of bolts required on the right side.
IE bolt #4, eight of them.., etc. I would have a shop manual before attempting...


http://www.boats.net/parts/search/Ya...ING/parts.html

I'm not sure about what other bolts need to be removed...Some penetrating oil wouldn't hurt.





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[cpostis]

Does anyone have a picture from the manual of which bolts (and how many) to be removed to pull the powerhead?

Does it help to remove the lower unit first, or is this not required? (thinking of the driveshaft)

Thanks,

mvh
Roar

I recommend you get at least one service manual for you motor. Your non-USA motor (90AETO) Should be equal to a USA motor (90TR). I have both a Genuine Yamaha Service, and Seloc repair manuals. My Seloc manual covers your engine well, including powerhead removal. It is publication # 1703. See the attached link.

https://www.amazon.com/YAMAHA-Repair.../dp/B0015GD1YK

The attachments are from Yamaha Service Manual for a 2004 motor that may or may not have the same specifications as you motor!

[Rlilleaas]

Thanks all,

Pulled the powerhead today - there must have been a gasket failure(looked like crap), no signs of corrotion

Aiming for assembly soon if the local yamaha dealer has the gasket in the shelf

[TownsendsFJR1300]

Well heck that was quick!!!!

No broke bolts either??

So looks like the gasket just failed with old age? If you can, maybe a pic?

Great work, saved a bunch of $ today BTW!!!

[Rlilleaas]

No bolts broke and everything came off easily.

Removed the lower unit /gearcase
Removed 4 longer bolts on each side (8 in total).
Removed 2 bolts in front of the engine
Removed 1 bolt in the rear/aft.

Total of 11 bolts removed

Disconnected fuel line (going in to the fuel filter)
Disconnected all electrical cables
Disconnected gear/throttles cables
Disconnected water-line/control-line
Gear link was a bit tricky, (however I disconnected this when the powerhead was lifted approx. 4 inches.)

Wiggled/rocked the engine a bit to break the seal (this is not possible if the lower unit/gear case is still in plase since the drive-shaft will then lock the powerhead in position)
Lifted it up and off.

Have now cleaned the surfaces and prepared for a new seal.

Hopefully this solves the spitting water issues. Some pictures before start and during enclosed.

Some pics enclosed More pictures to follow

[Rlilleaas]

More pictures

[Rlilleaas]

Last batch for now

[TownsendsFJR1300]

Thanks for the pic's and update!

Just a tad bit of crud and what's left of that gasket is nasty!!!


Just a side note, (post 10, pic #4) I believe on a T&T solenoid, it appears a bunch of green corrosion is under at least one positive terminal (un-less its green grease).. You may want to address that once you get all caught up...

Great job!

[Rlilleaas]

You are correct that the gasket looks nasty, however I am not overly confident that the gasket is causing the issues with the spitting water, the gasket surrounding the closed area where the "cooling pipe from the impeller" comes up looked relatively ok and thus should have sealed.

The water that came spitting out was colder than the water coming out from the control-flow out back, no water at all coming out together with the exhaust going to air.


It is a mystery. New gasket ordered and will arrive on Monday, so I have some time to investigate - all suggestions are appreciated.

And the green goo on the t&t cable connections is a lovely combo of grease and corrosion and salt - nasty - will be cleaned up

[TownsendsFJR1300]

That 0-ring seal is known to fail and as you see is only accessible with the powerhead re-moved. You may want to inspect that water tube (from the WP up to the engine) closely and probably replace that seal as you don't want to do this again.

I haven't read of any other reasons for that leakage there.

Was any of that gasket actually blown out/gone where it was leaking water?

Oh, and maybe check surfaces with a straight edge(probably not needed but why your there-(once cleaned)...