Serviced F150 returned with unusual noise

[paulwalter]

I have a 2012 F150TXR I purchased new on a Parker 21 SE. It went in to be "unwinterized" with 750 hrs, (new water pump kit, oil change, thermostat, etc). by the same mechanic who winterized it in Nov. I received it in the water and noticed two new sounds: One is a knocking sound when in Forward gear at the lowest rpm. The sound goes away when shifted to N, or when the rpms in F are increased, even slightly. The second sound is a Low rumble (the only way I can describe it is like a Harley motorcycle makes, although much quieter), when in N, at idle rpms. The sound goes to the regular, quiet, 4 stroke sound when the motor is tilted up, but still pissing water and returns with the low rumble when the motor is tilted back down. The gauges show normal water temp, and the water from the piss tube is always luke warm, never hot. I flush the motor every session, and the boat is kept in the water during the season (coastal NJ). Any ideas will be appreciated. Thanks.

[fairdeal]

sounds like your mechanic, when installing the water pump, did not perform this step:

https://vid.me/xiCb

[99yam40]

Knock in gear may be they did not set the retainer collar above the water pump correctly.
need to lift up on shaft when setting it.

have no idea what the rumble is

[paulwalter]

Thanks, I've seen on a few videos that the retaining collar not being set properly after a water pump change, or the wave washer not being re-installed can cause the knock at low rpm in F. I've also read that it is not harmful to the motor...I don't know if that is true, but it is really annoying and I worry about harming the motor. The mechanic says "nothing is wrong."
Any help on the (new) exhaust noise will be appreciated. Thanks.

[TownsendsFJR1300]

Plus 1 On fairdeals post.

It is literally In the YAMAHA SHOP MANUAL to pull up and knock the collar down. Just did my 2006 F150 about 3 months ago

No it won't hurt anything, just annoying as heck

[99yam40]

maybe a video with sound will help people with the exhaust noise you speak of

[pstephens46]

Thanks, I've seen on a few videos that the retaining collar not being set properly after a water pump change, or the wave washer not being re-installed can cause the knock at low rpm in F. I've also read that it is not harmful to the motor...I don't know if that is true, but it is really annoying and I worry about harming the motor. The mechanic says "nothing is wrong."
Any help on the (new) exhaust noise will be appreciated. Thanks.

Any unusual bubbles rising around the lower unit while idling in water? Other than what you have noticed before?

[paulwalter]

the only bubbles are when I tilt the motor up until the intake is (just barely)still in the water, then I can see bubbles coming up around the under water exhaust. There is still water running thru the engine. BTW, the exhaust noise stops at this point and the motor runs at the normal 4 stroke quiet idle. As soon as I tilt the motor back to all the way down, the exhaust noise resumes.

[99yam40]

could it be a vibration from the motor traveling through the bracket with motor sitting all the way down?

[pstephens46]

As mentioned, a video might be helpful.

[TownsendsFJR1300]

And both issues occurring RIGHT AFTER the service correct?

What is your warm idle RPM?

Can you tell if the sound is coming from the powerhead itself?

Plus 1 on an audio/video with good sound (with the cowl off if that helps pin point down the area)

[paulwalter]

i'll try to record a video which will demonstrate the sound the motor is making. I am concerned that the sound is being made just after servicing since the motor never had any unusual sounds for 750 hours???

[TownsendsFJR1300]

i'll try to record a video which will demonstrate the sound the motor is making. I am concerned that the sound is being made just after servicing since the motor never had any unusual sounds for 750 hours???

Agreed...

The idling knocking IS the retainer Not fully smacked down.

Look at the video fairdeal posted fully. Kinda long but you'll see where the tech pushes that retainer down.

[paulwalter]

Thank you for the replies. I think the knocking noise has been answered...the wave washer or retainer above the new water pump. I understand it is an annoyance but not damaging to the motor.
I made a short video with audio of the "exhaust" sound, but not sure how to upload it. To add to the description, when started cold, the motor runs perfectly quiet, as it has since I owned it (new). The sound, which sounds alot like a diesel truck engine might sound, begins as soon as the motor heats up to normal operating temp, as displayed on the gauges. This usually takes about 4 minutes running at idle 700 rpms. Thanks.

[pstephens46]

Many will upload the video to YouTube and then post a link here.