Harbercraft 1875 JMAX - Review

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The test boat for this review was provided by Harbercraft and Cascade Marine in Chiliwack.  Special thanks goes to Cascade Marine in Chiliwack who has provided great support and commitment to make this review possible.  


The JMAX is Harbercraft latest jet boat design.  It utilizes the same proven pre flex technology all Harbercraft boats do. 


The sides are made form 0.102" thick aluminum, while the bottom consists of 0.19” thick material.  Both bottom and sides are made from 5086 Alloy.


The boat’s MSRP is 32,225 CAD or 27,319 USD. 



The exterior is fully painted which makes the boat nice looking.  The inside is Zolatone coated unless carpeted.  The floor is plywood with vinyl. 




The hull is a delta pad design with 12 degree dead rise, lifting strakes and reverse chines.  A delta pad hull has excellent shallow water running capabilities and produces lots of lift which makes for an efficiently running shallow water boat.  Drawback of the delta pad hull is the harsh ride in choppy water. 



The layout of the boat is slightly different from previous Harbercraft jet boats.  The windshield of the JMAX is moved further forward as it is common with many other brands of river boats.  This will give more space in the boat but reduce the bow area. 


For a fishing boat this is a desirable setup.  For an all round boat one has to decide what is important: Bow area or inside space.


Another difference is the transom which is very short.  That’s a nice feature which further increases interior space.    



The pictures above show the transom with covers removed.   On the floorboard one can see how short the transom is. 


Inside the transom is the muffler and battery.  The remaining space behind the large covers can be used as storage. 


The JMAX hull length is 18’.  Harbercraft offers another 18’ Jetboat, the 1875.  Those two boats only have overall length and basic hull design in common.


The JMAX has a wider beam with 88” and was the first aluminum Jetboat available with the 160 HP JMAX 4 stroke motor.  The boat has a walk through windshield with 3 large glass windows.  The center window functions as door and opens to access the bow area and board the boat. 



The boat comes standard with Fishmaster seats.  The boat as tested and shown has the Sportsman package with Rivermaster seats and storage box in the bow.  The test boat came with box seats.  Standard equipment are front seats on pedestals.  Which to choose depends on preference … One has to balance dry storage with the box seats vs. more flexibility with rotating pedestal seats. 



The left picture shows the port mid seat.  On the right is the opened hatch / step in between the dashboard. 


The side windows are as short as in the 1875 and unfortunately not long as in the 19 foot boats which will probably allow for a little more splashing in the JMAX. 


The Hull is 88” wide and sides are 29” high.  Bottom width is a generous 66”.  The inside area of the boat has 2 seats parallel to the sides, facing each other.  The sides are carpeted which makes the boat more comfortable and also reduces noise levels in the boat.  In the gunnels on each side of the boat are 5 fishing rod holders.  3 additional vertical rod holders are mounted on the front of the dog house. 


The dog house is very different as on sportjet powered boats as it is long but low.  Between the dog house and the transom is a 10” wide walk through which allows to walk from one side of the stern to the other, which should be great for fishing of the stern.  Unfortunately the walk through is not flush to the floor.  Still this is a nice feature and allows for much better fishing from and access to the stern. 



This design is possible due to the motor and pump layout with is long but low. 







The JMAX’ canopy is not mounted on sliding rails but rather has mounts in fixed locations where the top can be attached.  This eliminates flimsy rails but also makes it a little more cumbersome to put the top up and down and out of the way. 


The boat comes on a single axle Karavan trailer with no brakes. 


The JMAX has an aluminum swim platform mounted on strong aluminum tubing which also serves as a pump guard. 



On the stern are two welded on brackets (the one on the port side can be seen in the picture above) where sonar transducers and zincs can easily be mounted.  Mounting a fishfinder transducer is easy on the JMAX since the pump only has one center reverse thrust that goes straight down under the boat.  That way transducers mounted on the side of the hull is not affected but the reverse thrust. 







The dashboard is simple and functional.  Steering and throttle is on starboard.  Throttle and thrust is controlled through a single control lever.  The pictures were taken of a pre production model and the final layout is slightly different. 


The boat has a tach, fuel gage and voltmeter.  Furthermore there is a 12V power outlet in the dash and the usual switches for boat functions, like navigation lights, bilge pump and such.  Unfortunately there is no electronic fuel monitor available. 


The port side has a lockable glove compartment.  The hull is a walk through design and the center windows opens.  There is a storage box that also functions as step to get into the bow.  Under the bow is a small storage area that can be accessed from the inside of the boat. 





Motor / Drive


The JMAX features a 160 HP engine.  The engine is a 4 cylinder 4 stroke with 1052 cc.  Peak HP is reached at 10.000 RPM.  This motor is exclusive to Harbercraft aluminum Jetboats. 




The chart above shows all relevant performance data of the boat, which will be discussed further in the sections below.  There are two ground speed over rpm curves.  One for the boat with brand new impeller and one with a severely beaten impeller. 





The motor having only 1052 cc makes it obvious that it isn’t a torque monster but rather a motor that gets its power from rpm rather from displacement.  The boat cruises at 45 KPH / 28 MPH at around 8000 RPM. 


The motor is derived from a motor that has been used in motor bikes and is also being used in PWC, snowmobiles and also other fiberglass sport boats.  It is however exclusive to Harbercraft aluminum jet boats. 



On the left picture is the oil reservoir with oil dip stick.  On the right the water cooled header / exhaust. 


As with every 4 stroke …. The oil filter….



The motor starts instantly as one would expect from a computerized 4 stroke motor and idles quietly and stable.  In idle, the motor is barely audible which makes for a nice change from a Sportjet.  Of course this changes once the motor revs up.  The JMAX motor hardly vibrates and hull vibrations are very minimal. 



The graph above shows noise levels of the JMAX (red) and other Jetboats for comparison as well as two Yamaha outboards on fiber glass boats. 


The JMAX’ noise level at cruise speed is about 88 dB.  This is much quieter as a 175 HP Sportjet which, depending on the hull cruises at about 95 or more dB. 


For comparison a typical outboard will produce 80 – 87 dB at the same speed, which is also strongly dependant on the design of hull and motor. 


The JMAX idles at just 74 dB which gives the JMAX the typical quiet 4 stroke idle with very little noise. 


Upon acceleration noise levels remain in the mid seventy dB.  As the boat comes on plane at about 8000 rpm, noise levels increase into the mid eighty dB and then climb up to 96 dB at wide open throttle.  The JMAX vibrates very little, which helps keeping noise levels down. 


The JMAX noise levels are higher as a 115 HP 4-stroke and 200 HP HDPI outboards produce but much less as Sportjet powered boats. 

Unfortunately the small and high revving motor makes for a high pitch noise that is subjectively less comfortable as the noise from a larger motor which rev lower. 


For an aluminum inboard Jetboat the JMAX has very low noise emissions. 



Although this is the first aluminum jet boat with this motor, the history of the motor in motorbikes, PWCs and snowmobiles makes it likely that this motor is mature and not prone to issues as sometimes encountered with brand new designs. 



The pump has been used in similar form in fiberglass sport boats and shouldn’t have “new design” issues. 




The pump has a very robust stomp grate with easy clean grate.  The stomp grate is activated through a large stomp handle on the swim platform.  Rocks and debris can easily be cleared with the stomp grate.  


One great feature of the pump is the ability for clearing out debris that is lodged onto the impeller or impeller shaft is a port inside the boat through which the impeller can be accessed and sucked in ropes or plants be removed.  Being able to remove debris from the impeller from inside the gives the operator some peace and should make navigating the boat in weeds much easier.  Sucking up ropes and water plants with the JMAX should be more an inconvenience than an issue. 



From left to right:  The pump with access closed port, close up of the access port.  On the right is access port opened with access to impeller shaft and impeller. 


The pump has a reverse gate with a single bucket that directs the reverse thrust down under the boat.  The single reverse opening is located below the nozzle and always open.  It produces thrust by the reverse bucket being lowered to cover the jet stream that then goes down and forward through the reverse opening. 


On the left: The reverse bucket open for forward thrust.  On the right: The reverse bucket closed for reverse thrust. 


This design works amazingly well for the size of reverse gate but does not achieve the reverse thrust of a Sportjet.  The reverse gate was however prone to jamming from small pebbles that wedge in between the bucket and the nozzle when in reverse.  It then requires manual intervention to free the nozzle which is otherwise stuck in reverse. 





The boat has adequate power for its size.  One has to be aware however that with 160 HP it is not a power monster but rather a reasonably but not overpowered boat. 


Still the boat feels agile and at no time underpowered with 2-3 people and light gear on board.  The boat comes  on plane easily and accelerates quickly.  Boat handling is much like one expects from a Harbercraft hull.  It turns sharp and quick and easily.  One always feels safe in the boat. 



Typical for a jet boat is the rooster tail.   It is not shooting up but sprays straight back.  


The boat reaches a top speed of 66.7 kph or 41.5 mph, which is slightly less than a 175 Sportjet, which will reach about 70 kph or 43.5 mph in a similar size boat.  The 175 Sportjet being faster is no surprise as more peak HP means less more speed. 


The small difference in top speed between the JMAX and a 175 Sportjet is rather small and hardly a concern. 



Fuel Consumption


Unfortunately it was not possible to get fuel readings of the test boat.  It did not have an electronic fuel meter nor a flow meter.  Hopefully Harbercraft will be able to offer an electronic fuel use gauge in the future. 


Data in this review is based on fuel consumption values that are available for the 160 HP motor. 


Since those are not values measured with the test boat all fuel use information in this review shall be used and treated as an estimate only! 



The graph shows the fuel consumption over speed for the 18’ JMAX compared to an 19’  Harbercraft 1975 with 200 Optimax Sportjet. 


The JMAX cruises at respectable 0.4 l / km or 6 MPG.  This is a good value for a Jetboat and better than a 175 Sportjet. 


This should give the JMAX a theoretical maximum cruising range of 340 km / 210 miles with its 130 l / 35 US gallon tank.  As with any boat one should never plan trips based on this theoretical cruising range as factors like wind, waves and current can drastically reduce the actual range. 

When comparing fuel use to a 200 Optimax Sportjet it does seem like the JMAX should do better.  The only fuel use data is available for a Harbercraft 1975 with 200 Optimax Sportjet.  In the longer but narrower 1975 the Optimax delivers very similar fuel use of 0.42 l / km or 5.7 MPG while delivering 20% more horsepower. 


Again, the fuel consumption for the JMAX was not measured and is based on published values and as such should only be seen as an indication. 


The fuel consumption of the JMAX is very good and will allow one to use the boat without worrying too much about fuel cost. 






Unfortunately no performance data for a Harbercraft 1875 with a 175 Sportjet was available.  The only available acceleration data is for an 18’ Thunderjet with 175 Sportjet and a Harbercraft 1975 with 200 HP Sportjet.  The Thunderjet is a good 500+ pounds heavier and so one should take this in mind when looking at the data.


The JMAX accelerates quicker off the line until into the mid 30 KPH.  Then the stronger 175 Sportjet pulls away. 


This data is pretty much as expected … the lighter boat with slightly less HP will get off the line quicker.  Quick off the line acceleration is important for a Jetboat. 


For comparison data from a Harbercraft 1975 XL with 200 HP Optimax was added.  As expected this boat out accelerates both other boats by far, even though during the test it was loaded heavier and was running an old impeller.    



For a river boat one would prefer quick off the line acceleration for maneuvering shallow rivers and for getting the boat on plane as quickly as possible.  This puts the JMAX ahead of a heavier boat with 175 HP Sportjet.





Ride is pretty much as one would expect from a 12 degree delta pad hull.  The boat comes on plane quickly and handles the occasional wake from other boats and small waves well but it is clear that this is not the boat to tame the kind of chop that is usually found on big lakes.  This boat is not a “Heavy Chop Tamer” but heavy chop should not be encountered on the river waters the boat was designed for.  Since the boat is quiet heavy it should be acceptable to tackle lakes with it as long as one doesn’t expect deep V glass boat ride quality. 


As with all boats the JMAX is a compromise and does great in shallow water but of course this comes at the cost of rough water handling. 


Being designed as a river boat, the JMAX does exactly what it was intended to. 






The JMAX is a nice addition to the aluminum Jetboat market.  Hull design and handling is excellent.  The interior layout makes for lots of available space for people, gear and fishing. 


The motor / drive combination works very well with the boat and is quiet and fuel efficient.  The JMAX motor is the only mid range power 4 stroke inboard Jet available today.  The options are 2 stroke Sportjets or V6 or V8 inboard jets.  The latter have more power but  use more fuel and are considerably heavier. 


The JMAX is a great efficient mid size river boat. 



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