Super Jet 155 OEM pump build question

96superjet · Aug 11, 2018

I’m building a 155 OEM pump with Skat 6/12 large hub prop to run in my JetManiac 781 powered Phantom. Prior to final assembly, I gotta decide which pump cone to throw on it. I have the OEM plastic cone, large and small solas cones. What you say???

Also doing some home boring of the reduction nozzle with a 40 grit flap wheel. Seriously the worst self imposed job ever.

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96superjet · Aug 11, 2018

Never mind...

Turns out Solas cones do fit in the stator bearing section, but the bolt holes don’t line up. OEM plastic cone it is.

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Harbor · Aug 11, 2018

You can use a mini carbid to grind the outer wall a little further out. Did mine, didn't take much to do..

SmittySX · Aug 11, 2018

Bigger cone and a stock bore nozzle with that prop.

zyxwvu44 · Aug 15, 2018

How does it run? I'll be using a stock 155 in my phantom with JM 781...

96superjet · Aug 15, 2018

zyxwvu44 said:
How does it run? I'll be using a stock 155 in my phantom with JM 781...

I’ll update the post soon. I gotta put the grease seals in the pump then shim it up in the hull. Should be ready to rip at that point.

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steve711 · Sep 12, 2018

What Pump shoe /brand are you installed ?
Thanks

96superjet · Sep 13, 2018

steve711 said:
What Pump shoe /brand are you installed ?
Thanks

It's a Jet Dynamics aluminum 155 pump shoe. That's what Josh includes in his Phantom Builds.

So... I never really came back here and did an update on the performance of my OEM 155 pump setup and Skat Track 6/12 prop with 5mm cut back.

At first I wasn't terribly impressed, but it really had more to do with my carb tuning. Mind you I ran this same motor setup with a Solas 144mm Mag pump and it seemed to hit fairly well. When I went to the OEM 155mm setup, it felt fat on the bottom end. I did not go back and make significant pop-off, low jet and high jet modifications. Instead I simply fooled around with my low and high adjusters and she totally came to life.

One thing, I've learned lately about carb tuning is cranking in your high screw. I went from 1 1/2 out on high adjuster into 1/2 turn out. DAMN!!! it woke the ski up. Of course, I'm not out chasing boat wakes with this ski. It's all about the low end brap. So... overall I'm pretty pleased with the 155 OEM setup and the cost is WAY less then going with a 155 mag pump.

steve711 · Sep 13, 2018

96superjet said:
It's a Jet Dynamics aluminum 155 pump shoe. That's what Josh includes in his Phantom Builds.

So... I never really came back here and did an update on the performance of my OEM 155 pump setup and Skat Track 6/12 prop with 5mm cut back.

At first I wasn't terribly impressed, but it really had more to do with my carb tuning. Mind you I ran this same motor setup with a Solas 144mm Mag pump and it seemed to hit fairly well. When I went to the OEM 155mm setup, it felt fat on the bottom end. I did not go back and make significant pop-off, low jet and high jet modifications. Instead I simply fooled around with my low and high adjusters and she totally came to life.

One thing, I've learned lately about carb tuning is cranking in your high screw. I went from 1 1/2 out on high adjuster into 1/2 turn out. DAMN!!! it woke the ski up. Of course, I'm not out chasing boat wakes with this ski. It's all about the low end brap. So... overall I'm pretty pleased with the 155 OEM setup and the cost is WAY less then going with a 155 mag pump.

Thanks
I really appreciated your infos