Glossary . . . Pump Items
Common Name: Nozzle, Snout, Cone, etc.
Function: Two-fold: First off, it "straightens" the water that is being spun/thrust out by the impeller (enclosed propeller). Secondly, it narrows-down the diameter of the water stream - increasing the thrust being developed.
- Early 50hp bikes had the shortest pump shaft, nozzle with smooth tip and raised inner flange.
- When changing to a Skat Trak impeller, you might have to machine-down that inner surface so that the impeller won't make contact.
Common Name: Wear RIng
Function: Replace-able collar that surrounds/encapsulates the impeller.
Pic: Here's a 3d version of a wear ring and here's a pic
- Early 50hp wear rings probably didn't have the alignment knocks and o-rings in them
- Although some folks have tried to repair them with various techniques (bondo, ss liner, etc) it's usually most cost effective to just replace them
- If yours is grooved, then the holeshot will be greatly decreased.
Common Name: Alignment pins, knocks, sleeves, etc.
Function: Two-fold: First off, it "seals" the joint between the wear ring and the pump. It also may help with alignment of the two pieces. The o-rings ensure a water-tight connection.
- There has been more than one manufacturer of the wear rings. So . . . sometimes the alignment/fit may need a little massaging to get to work right.
- Corrosion can wallow out the holes a bit making the knock fit very loosely and/or not at all.
- Sometimes they get stuck in the pump - sometimes in the wear ring
Common Name: Impeller, Prop, Screw
Function: Generates thrust. Creates great frustration if worn or chewed up. Makes great paper weight.
- 50hp bikes had the what is referred to as the "straight blade" aluminum prop.
- Later years came with what is referred to as the "clipped-ear" impeller. Also referred to a the "high-altitude" impeller
- Aftermarket impellers were available in aluminum (maked HP), Bronze, and Stainless Steel
- Skat Trak is the only company offering impellers anymore (that I know of)
- They are all left-handed thread and can sometimes be a bear to get off. DO NOT take a grinder to it to remove it - you might do this
Common Name: Speed Plug
Function: Straightens out the water flow by reshaping the roof of the pump intake. Greatly increased the high-speed performance of a wetbike
- There has been more than one manufacturer of these things. Some are fiberglass, others were aluminum (welded in).
Common Name: Pump
Function: Houses the gears, shafts, and oil connecting the powerhead to the impeller. Serves as a the mechanism to mount the ski to the wetbike.
- Early 50hp pumps had 2 roundish zinc anodes mounted to the front pump cover
- 60hp pumps had the 2 oval anodes mounted to the back rear corners.
Common Name: Pump shaft, input shaft
Function: Connects powerhead crankshaft to ring/pinion assembly (transmission).
- 50hp pumps had a short shaft
- 60hp pumps had the longer shaft
- You can put a 60hp motor on a 50hp pump but you cannot put a 50 on a 60 without changing the pinion shaft
Copyright 2012 Capt'n Obveeus