Hearing loud ticking/clunking noise after water pump installation.

[byron.akhavi@gmail.com]

I have a Yamaha 2019 F40LA outboard (serial # 6bgk-1002641) and I attempted to change the water pump.

I removed the lower unit and changed all the water pump components. Then I tested the motor and confirmed that the unit shifted and pumped water.

I noticed a loud ticking sound when I started the motor (post the pump change). The motor sounded different, and this loud ticking/clunking noise was heard in neutral.

It was constant and I had the motor in neutral and at idle speed.

It was heard when I tested forward and reverse gears. The motor was started in a 55-gallon drum, to provide ample water.

I noticed that I could not find the old gasket located under the metal thrust plate. I dropped the lower unit again and confirmed that I placed the new gasket over the old one (double gaskets installed).

I removed the second gasket and reinstalled the new one. Then put the pump together again for a second time.

I followed the service manual steps. I did not need to remove the woodruff key to remove the pump parts, and just left the key in place.

I confirmed the pump impeller was secured, to the key, by holding the impeller and trying to turn the drive shaft clockwise. The impeller would not move.

When I started, after removing the second gasket, I could still hear this clicking/ticking noise.

The pump pumped water. I was able to shift gears. .I was able to turn the prop in both directions (in neutral gear).

I just can't think what I may have done wrong.

Could you give me an idea why the motor would run with a loud ticking/clunking sound? I only have about 40 hours on this motor.

I know I originally installed the pump incorrectly, with two gaskets under the thrust plate.

However, I am not sure if I caused serious damage since the motor did not overheat and ran....just with this loud noise.

I changed the gear oil and motor oil in the fall. Confirmed I had proper engine oil. Have not checked the gear oil but I know it did not leak over the winter storage (in my garage).

I installed the unit without any resistance (both times). The drive shaft splines, shift gear and water tube were installed easily by hand (never forced the unit upwards....just slid into place).

I think maybe the metal cup was not installed properly but I aligned the tab into the housing and it snapped in.

I used silicone brake grease on the thrust plate, inside the cup and on the impeller fins.

Just worried about running this motor in the lake, with this sound.

If you guys could give me some insight into possible causes, I would really appreciate your expertise.

Thanks for your assistance,

[TownsendsFJR1300]

With my F150, you should pull UP on the driveshaft when installing the retainer to the impeller..

That gets/keeps the slop out of the shaft doing what yours is likely doing.

I use an open end wrench, then tap gently around the keepers downward (after removing the cup).while pulling up on the shaft.

.

[Keithbaja]

Well, to start with do not use double gaskets anywhere.. Double seal's is a different book. Never use any lube on impeller. A light spray of windex. Try to always run motor asap after a impeller R n R...inspect the rubber seal behind the w/p for damage or missing completely. Its flat,, about 2-3 inches long and seals the exhaust channel. (Megaphone) and as townsend said about lifting up on the driveshaft. Also turn the shaft clockwise when installing pump

[99yam40]

I do not see any keepers like Towns mentioned.
Is it possible that your shift linkage is out of adjustment and the clutch dogs are hitting while in neutral?
but that would not happen in forward and reverse gear.
so I am at a loss to what is going on

[zenoahphobic]

I do not see any keepers like Towns mentioned.
Is it possible that your shift linkage is out of adjustment and the clutch dogs are hitting while in neutral?
but that would not happen in forward and reverse gear.
so I am at a loss to what is going on

No doubt the logical conclusion , but OP says the noise is still there in forward and reverse?

[zenoahphobic]

If you are going to pull apart and reinstall as suggested above, I would wash the oil off the impeller with dishwashing liquid and install with this detergent to avoid a possible future binding of the impeller, even though brake grease is partially water solvable.

[Keithbaja]

Johnson and Volvo penta impeller come with glycerin lube.. The best. No grease Ever !!

[TownsendsFJR1300]

I do not see any keepers like Towns mentioned.

Just looked it up and I don't see a keeper for the impeller.

I'd guess that 2nd gasket allows some up and down movement

I use Palmolive soap for the install and make sure you rotate the shaft clock wise as you install the cup.

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[byron.akhavi@gmail.com]

Thanks for the advice everyone. I tracked down the issue. The root cause was low fuel supply to the fuel pump. The ticking noise was the pump trying to obtain fuel. Purchased and installed a new Yamaha fuel line. Used the new bulb to prime with fuel. Then started perfectly.

The water pump pumps a steady stream at fast idle. Ran it for 15 minutes in a 55 gallon drum. Going to test in the lake on the weekend.

[99yam40]

Good to hear, thanks for reporting what it was.
had me really thinking hard to figure out what it could have been