outboard jet help

[Mike Agnew]

need some help with seting up an jet it is a 80 hp 4 stroke on a 18 ft alum lowe with a tunnle bottom . i have never set one up before and some input would be greatly appreciate.

thanks mike


ok travis i know this is your cup of tea

[sosmerc]

What model, brand and year of engine? Did you get it from the factory with a pump? I assume the engine is a 20 inch (meaning, you will need a 27inch transom height with a pump).
Not much to do in the way of setup, the leading edge of the pump needs to be even with the bottom of the boat and if there is a small tunnel you can come up just abit. I've seen some where a flexible piece of stiff rubber or plastic can be run from the back of the boat to just over the leading edge of the pump...helps to prevent sucking air.
There are stainless impellers available now for most of the pump models...they improve performance slightly. What else in the way of "setup" concerns did you have? (years ago I used to rig alot of jet boats for a dealer in Salem, Oregon). We even put tiller handles and jet pumps on V-6's and ran them on flat bottom 18ft. sleds.

[Mike Agnew]

thanks sosmerc the motor is brand new 80 hp 4 stroke yam the biggest ? is how do you know the shimming is right specialty jets made the pump . i had to asemsemble the pump toghter and install on motor . they gave no shimming info at all nether dose yamaha . i put it all together today tomorrow i plan on puting it on the boat . but need some help the boat is empty right now . but it gets a consle up in the front plus the rigging i have heard that the setup is really tricky with a jet to keep it from sucking air . but the same people that say that is the ones that dont know any thing about it . dad told me to put the motor 3 inchs below the bottom of the tunnle but you say even so should i start between u and him for safe measure . or save my self some trouble and mount it even .

thanks mike

[sosmerc]

Mike, is there any chance you could post a picture of the boat bottom? Normally, I would say just set it "even" with the bottom...but I'd sure like to see the hull configuration first.
Is the pump brand new? I like to shim the impeller until is just scrapes the liner, then remove one shim to add a touch of clearance. Keep in mind that the impeller tends to climb down tighter into the liner as you apply power...as it ages and the bearings permit more shaft movement, you may have to adjust shims...but also, the liner and impeller wear and this creates more clearance between liner and impeller. For more info regarding your pump, as well as obtaining any pump parts you may need, you can call Outboard Jet at 510-562-6049.
I don't do much jet work here on Hood Canal in Washington State, but if I can help you feel free to call me at 360-275-4690.
I can still get jet pump parts and will sell at my cost plus 10%.

[Laker]

Mike
we just set up a skinny water rig for my cousin... 17 warEagle, 90 HP yammer. Pump inlet leading edge is run 1.5 inches above the bottom 19 inches behind the bottom using 2.5 inch wedges, stick stear. Super cool outboard powered boat that will run in 6 inches of water up the rapids!.
Also I need to get a set of Premium Agnew Looper rods for the mod V4.
Saw Bruce's Xflow agnew rods yesterday! NICE Work!
Let me know the Avaliability.
Chris
262-703-0341

[Mike Agnew]

thanks guys my printer dosent work so i wrote what info you guys gave me and takeen it to work if mike martin comes by to day i get him to take some pic of the boat .

sosmerc so what you are saying is most of the shimmes are at the bottom of the impeller . man i dont know what i am doing with this thing yes it is an outborard but that sh... stops at the lower unit or jet .


chris i am pretty sure we got some rods what kind of wieght are you looking for . i love my rods they do look killer good . it takes me just about a day to do a full set of 6 . i us 8 belts and 2 polishing belts alot of water but i do it with my hands on gloves so the rods never get hot that i cant hold them .all rod cut to the same wieght then sent to you .

thank guy mike

chris i will callyou tonight . got to get to work now

[Mike Agnew]

thanks again guys got the boat ready to go to the lake today . the only ? is now the motor is 1/2 below the bottom how much is it going to efect the performance on the boat . thanks for the phone # to outboard jet sosmerc and your help . what you told me on the impeller was the way to go and the same on the motor height . the real problem is the junk that lowe sent to raise the motor up it wont be long before the transom comes out . iam trying to talk the boss in doing some more to the transom so i dont have to do it later when he rips it out

a big thanks to you guys for the help and info

mike