Pump-Jet Outboard Users ?

[fireman2151]

I am a memeber of a Swiftwater rescue Team. We are currently looking
for a replacement for our 25hp outboard prop that is currently mounted
on a Zodiac IRB.

I was interested if anyone could provide their thoughts on the
performance of the pump jet outbard on inflatables. Just for clarification I don't mean the traditional jet drive outbaord but the newer style. Does it
provide enough power comparable to a prop? How does it handle vegitaition and debris? How does it handle accidental strikes of submerged objects i.e.
rocks?

Any comments or thoughts about the motor you could provide would be
greatly appreciated as I haven't been able to find much information on
the peformance of the motor. Thanks in advance,

P.S. dont mean to be a bother but I am posting this in two different threads to reach the most users possible. Thanks.

[lexfd5]

Are you talking modification to your existing engine or redoing your entire craft with an entirely new engine?

[fireman2151]

We are going to replace the old outboard all together. It is a 25hp second hand rebuild. IT doesnt quite have enough muscle for our 15' Zodiac Grand Raider we just procured and is giving more reliability problems. We are thinking about the Evinrude RescuePro series motors if we go with pump-jet. Basicly its either pump-jet or prop we aren't considering jet drive due to lack of reverse, loss of HP and clogging problems our Dive team has experienced.

[lwestbrook]

We have a Zodiac MK II GR that we have a Mercury Jet 40 on. It is an outboard 2-stroke engine with 60 HP. We use it for water rescue operations. It is set on the boat so that the intake which is on the bottom is level with the bottom of the boat. We can get in as shallow as about 2 feet. It takes a beating with rocks and such pretty good. We use it mainly in the Cape Fear river on the north side of Fayetteville, NC. We have lots of shallow rocky areas (falls). It has plenty of power even when the river is high and running fast. We have taken it into some lakes for training with no problems on clogging up with weeds and such. Hope this helps.

[NJTF1Bowman]

I am a memeber of a Swiftwater rescue Team. We are currently looking
for a replacement for our 25hp outboard prop that is currently mounted
on a Zodiac IRB.

I was interested if anyone could provide their thoughts on the
performance of the pump jet outbard on inflatables. Just for clarification I don't mean the traditional jet drive outbaord but the newer style. Does it
provide enough power comparable to a prop? How does it handle vegitaition and debris? How does it handle accidental strikes of submerged objects i.e.
rocks?

Any comments or thoughts about the motor you could provide would be
greatly appreciated as I haven't been able to find much information on
the peformance of the motor. Thanks in advance,

P.S. dont mean to be a bother but I am posting this in two different threads to reach the most users possible. Thanks.

I had asked the same question at my first swiftwater deployment, the answer given was the cost and down time for the replacement of an impeler as to a prop was too high. We have cages on all the outboard props and with the type of swiftwater calls we get there is a load of trash in the water that would just eat a water-jet impeler.

[jtobbe]

We have 5 boats that we use that have a Johnson 30hp pump jet on them. They work pretty good but lose their bite in white water. The impellers need pretty close tolerances to the housing to provide the most thrust. If you accidently suck up some gravel it may chew the impeller up and it will lose some of its power. The changing of the impeller takes a few minutes, but is not to hard to do. Ours has 6 cap screws a cotter pin and a castle nut. Each boat has a box we keep in it and it has tools and a spare impeller.