290 hose connection leaking

How hard is it to replace the hose connection? I was troubleshooting an overheating issue and realized the hose connection is leaking. It doesn’t look too accessible without removing stuff.

Robert

The water neck fitting, or the chrome tube that extends through the transom shield?

Here is an AQ series aluminum water neck fitting. This part is a wear item, and should be replaced routinely.
Remove transmission ONLY for access to this fitting.
Apply heat to the suspension fork before removing the two small screws.

The special beaded gasket installs with the bead facing downwards, and the bead must be lubricated as it rotates against the top of the pivot tube.




Here is the chrome suction side tube that penetrates the transom shield.



These are chrome plated copper and are extremely soft.
Use caution if removing one.


The S hose joins these two parts in the line of seawater pump suction.




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Yeah it’s the neck fitting. Thanks. Do you mean remove the transmission ONLY if I need access or I’m going to have to remove it for access?

Rscottdds said:

Yeah it’s the neck fitting. Thanks.
Do you mean remove the transmission ONLY if I need access or I’m going to have to remove it for access?

Click to expand...

In order to get into this area, you will want to drain the gear oil.
Next, remove the helmet pin and raise the helmet up and out of your way.
Next, remove the rear shift mechanism cover.
Next, remove the vertical linkage rod from the eccentric piston arm.
Now loosen the band clamp from the AFT area of the drive shaft bellows.
Gently push the bellows from the transmission clamping collar.
Now remove the 4 cap screws that secure the transmission to the Intermediate housing.
Raise the transmission up, turn it sideways a bit, and lift it up, pull it AFT to release the drive shaft's yoke from the PDS, and out.
Watch for and inventory all shims!

Now the area is open for easy:

Water neck fitting replacement
S hose replacement
Shift cable replacement
drive shaft bellows replacement
etc.

When going back together, replace all 4 O-rings with new OEM.
dip stick O-ring
drain plug O-ring
oil drain back tube O-ring
large bearing O-ring.

Be sure to use a hand held impact driver on the drain plug fitting.
A few gentle blows with a rubber hammer will do it.


If s/p drive...... 30W non-detergent engine oil
If DP drive...... GL-5 gear oil


This is a fairly easy job.



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Thanks for your help. Much appreciated. Is there any other recommended maintenance items that I should do with the transmission off?
Robert

Depending on the model 290 transmission, look closely at the vertical shaft's split ring keeper.
Look for signs of the keeper expanding at the lower end.
The sides should be perfectly parallel to one another.
If not, it is expanding and should be replaced!

If so, follow the OEM procedure and then check the clearance underneath the top LH nut.

Thanks. I will check that. One last question. Where is the exhaust supposed to exit? Does it all go out the back of the drive where the flappers are? When I run it on the trailer hooked to ear muffs the flappers don’t open much and most of the water/exhaust exits somewhere in front of the drive. When I manually open the flappers then water will start to spray out and the exhaust sounds different.

While on the garden hose and water muffs, at low speed the wet exhaust will exit the low speed exhaust relief ports.
At higher speeds, the wet exhaust will exit the main back flow prevention flapper..... i.e., the main exhaust outlet!


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