Why no pee?

[guitarzan413]

Good morning all, I just had to replace my damaged gearbox on my 06 Yamaha F150tlr. I bought an aftermarket because i can't afford a factory part and now I can't get the water pump to prime unless I cover the whole top of pump. If I don't, it won't prime system. My old unit just needed the pick up screen covered. I replaced housing and impeller but still won't prime unless it's completely submerged. Any help would be greatly appreciated considering manufacturer is closed for holidays and I want to fish!!!!

[99yam40]

well I would think that when you put the boat into the water the water level will be above the water pump when you start it, so it will prime just fine

[guitarzan413]

I have to bury it on the trailer in water to cover pump to prime it. I have never had an issue as long as pickup screen was under water on old unit. Why would I need to completely submerge this one?

[walleye1]

I think you are missing a part in the wp housing that seals the pick up tube.

[pstephens46]

I think you are missing a part in the wp housing that seals the pick up tube.

Take it off and verify the grommet/rubber seal is in place where tube connects to pump housing. Take the boat out and get it up on plane and see if it still pees. Trim the motor also to
make sure. My F150 needs a good bit of water to pee. Takes two hoses in the driveway.

[TownsendsFJR1300]

Take it off and verify the grommet/rubber seal is in place where tube connects to pump housing. Take the boat out and get it up on plane and see if it still pees. Trim the motor also to
make sure. My F150 needs a good bit of water to pee. Takes two hoses in the driveway.

Plus 1 on the o-ring seal...

I believe it's part #2: https://www.boats.net/catalog/yamaha...casing-drive-2

My 06 F150 pee's easily on one hose, just on muffs, never an issue:

https://www.flickr.com/photos/147134...6/34909194323/

[Thomas Gillane]

Kill switch on the 703 control box has a plastic lock/jam nut to hold the switch. Anybody know the size and type of nut it is. Mine cracked and I can't find one at any of the big box stores.

[TownsendsFJR1300]

Kill switch on the 703 control box has a plastic lock/jam nut to hold the switch. Anybody know the size and type of nut it is. Mine cracked and I can't find one at any of the big box stores.

Can you start your own thread vs hijacking this one?

Simply click "start a new thread"

https://www.amazon.com/Yamaha-Outboa.../dp/B002GUJM4C

[99yam40]

From what I have read there are a lot of them like that.
hard for the pump to suck on air to get water up to it.

everything I have read says to submerge to cover water pump so you do not end up hurting the rubber impeller with it turning dry

[TownsendsFJR1300]

everything I have read says to submerge to cover water pump so you do not end up hurting the rubber impeller with it turning dry

That or pump (hose/muffs) water into the intake ports..

[pstephens46]

Plus 1 on the o-ring seal...

I believe it's part #2: https://www.boats.net/catalog/yamaha...casing-drive-2

My 06 F150 pee's easily on one hose, just on muffs, never an issue:

https://www.flickr.com/photos/147134...6/34909194323/

My F150 has never peed on muffs. (Sounds so perverted). Three different water pumps. If I bought better muffs maybe so

[guitarzan413]

I think you are missing a part in the wp housing that seals the pick up tube.

I thought so too. Checked for seal below press in grommet on housing. It's there. Even went to pump housing off old lower unit. It will pee on hose perfectly but unless I submerge the whole chassis to submerge entire pump, it will not prime. I had not had any issues with old unit priming. It's not making sense to me. My 2 stroke will prime with just pick up screen submerged, this one did until i changed lower. I can't see any missing seals, grommets, retainers or gaskets.

[walleye1]

I'd go with old housing

[guitarzan413]

I'd go with old housing

I did. It's doing the same. Great on hose, must submerge at ramp

[pstephens46]

I did. It's doing the same. Great on hose, must submerge at ramp

Yamahas are finicky. Put it in the water and run it. Test it. Get it on plane and trim up to most efficient running speed. Does it still pee? Alarm?
No? Good to go.