Outboard Jet questions

[Flight01]

Anyone have an OB jet that can answer this

I have a Merc 25 jet. When idling I can see good flow out the tell tale and motor sounds good . What I’ve noticed is water squirt out of 2 spots
Both are are center of pump, transom side. We will call it 12 o’clock
One right on the pump houseing that really squirts and one above it in a recessed hole where pump mates with leg, thisnisna bubbling one. Never looked for it before I don’t know if it’s supposed to or not. I don’t see these places identified on any schematics.
Can’t say I’ve looked while running on the river
This was just running in a wheelbarrow full of water as I just changed the oil and wanted to check filter for leak and look at oil level.

Thanks

[Positrac]

That’s messed up. The old Merc is on its last legs for sure. I’ll take it off your hands for parts...

[Flight01]

Haha. Nope

Just not used to jet pumps. Not sure where this water is coming from.
Motor is tee top mint. Just wondering about the pump unit

[Positrac]

I believe it has something to do with reducing water pressure through your motor. The last two Outboard jets I had both had them.

[Flight01]

What size boat and outboard motor did you run ?
I’m running a little 14.5’ legend widebody. With the 25 factory Merc jet.
I’m not sure how they can call it 25 at the jet. It’s a 30hp head with 30% loss Should be a 20hp thrust? No?

[Flight01]

Changed out the wear ring. About it time I’d say. Last owner should’ve done this long ago.

[Positrac]

Hey Flight, I had the same pump you are using but mine was on a 25hp Merc 2-stroke. I also had a 115/80hp factory Yamaha. All the pumps on outboards are made by California Jets though, just different sizes.

I’ve ran wear rings in the same shape as yours with about .080 clearance and you would be surprised how little difference a new wear ring with .020 clearance really makes. I was really anal about shimming the impellers until I decided to do some tests with the gps prior and after changing wear rings. Not a huge difference in every test I did. I’d still change them out every year but I wouldn’t bother shimming them all the time.

I know everything you read says different but that was my observation...

My Merc was bumped up to 30hp with a bigger exhaust tube and carb work. I figured it would be 20hp at the pump. Plenty on a 1448 Starcraft Jon.

[Flight01]

Interesting. I’m going through the same stage now. Was getting 30km/hr upstream with 2 guys and 40 downstream.
Speed is ok I want to be able to take more weight.
I will see what happens now with a new ring.

Thanks for the tips.

[Positrac]

No problem. If you need someone to help weigh the bow down don’t hesitate to call. Lol.

I sold my Explorer to a fine gentleman on here a couple months ago and I’m going through withdrawals.

[Flight01]

For sure we will have to hit the river one day

How far did you go with your jon boat?

[Positrac]

Originally Posted by Flight01

For sure we will have to hit the river one day

How far did you go with your jon boat?

Basically everywhere up here. Early season in high water was never an issue but come Sept-Oct when water levels got lower I’d start to hit the rear of the pump. So light and relatively slow though the motor would just kick up with no damage.

I went as far south as the Cascade Rapids on the Athabasca a few times. I don’t know if I would recommend that in a small Jon though. Getting through Mountain Rapids was a bit hairy and I turned around there a few times when the water wasn’t right.

I also boated the Firebag quite a few times. A small boat was great there because you could launch it right on the Firebag and save the two hour run up from Barge Landing that a bigger boat would need to take.

I still see my old Jon pulled up to the beach at Pedon’s Point across from Mac Island once in a while. I’d consider buying it back if it ever came up for sale it worked that well. I’d consider buying my Explorer back that I just sold if it came up for sale too so maybe I just have a hard time letting go...lol.