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HamiltonJet HJ212 Waterjet


Now 10,000 built!

The HJ212 model of waterjet was introduced in 1992 as the replacement for the dated 770 series of multi-stage jets.  The intension behind the HJ212 was to introduce modern, slightly larger jet into the smaller end of the HamiltonJet line.  The pump needed to be affordable, efficient, compact and be able to handle the “white water” rivers of the New Zealand and North America.

Key design features of the 212 include…

  • Much improved pump geometry.
  • A more efficient hybrid-mixed flow impeller design.
  • Optional Turbo impellers that incorporate the efficiency of a single impeller with the anti-cavitation characteristics of a multi-stage.
  • A size increase of about 15% to better handle the power of today’s V8 engines.
  • Tight turning, highly effective JT nozzle design vs. the older less effective T3 design.
  • Split duct reverse vs. the older clamshell type.
  • A space saving close coupling option that eliminates the need for a conventional H bar driveline.

The design improvements incorporated into the HJ212 resulted in a waterjet that would handle about 25% more weight, cruise at a much lower rpm, burn less fuel, and reach a higher top speed, not to mention turn and stop more efficiently.  The HJ212 can also handle larger, more powerful engines than a 773.











What size boat is the HJ212 suitable for?

Most HJ212 boats with a single jet are 4.3m (14') to 7m (23’).  Twins typically are about 8.5m (28’).  Most boats with a single jet weigh about 1200kg (2650 lbs) to 2500kg (5500 lbs).  Twin jet boats may be about 3000-3600kgs (7,000-8,000 lbs).  In both cases more weight can be carried if needed.

Will the HJ212 drop right into the spot where a 773 was?

Unfortunately no.  The HJ212 is a bit bigger and has a slightly different transom angle.  Depending on how your engine is coupled and how tight the engine compartment is you may have to move the engine ahead slightly.  The modifications can usually be done without a great deal of problem, but some modification will be required.  At a very minimum the intake of the old jet must be removed and a new intake block welded in.

How about other types of waterjets - is removing them and replacing them with a HJ212 a problem?

Most of the old fashion “pressure pump”-type waterjets are smaller than the HJ212.  Hence, the intake and transom holes tend to be smaller; this usually makes it easier to open things up a bit and weld the HJ212 block into place.  Waterjets manufactured by other companies may have similar or quite different intake and transom hole positions and sizes, so you will need to discuss the options with your nearest HamiltonJet Distributor. 

Over the years since the HJ212 was introduced lots of people have pulled out older jets, both older Hamilton’s and numerous other brands. It’s safe to say that the satisfaction rate with the HJ212 is very, very high.

What’s a Turbo impeller?

The Turbo impeller is basically a dual stage impeller, rather than having a single row of blades like a conventional impeller, it has two.  They share the duty so to speak, allowing us to put more “metal” inside the jet where it will do the most good, reducing cavitation.

Do you offer standard impellers as well as the Turbo?

We do, but we almost never sell them.  The Turbo accelerates better, hangs onto aerated water better and generally improves overall handling versus a conventional impeller.  In short, for the minimal cost difference there is just no reason not to use the Turbo.

Do you make more than one Turbo?

There are three different ones.  The 2.4T is for the small block Chevrolet 350 and Ford 351 cubic inch engines, the 3.4T was designed for Chevrolet 454 and Ford 460 engines and the 4T is intended for the Chevrolet 8.1L but may also be used on some “built” 502 Chevrolet.

What kind of full throttle rpm should I get with the HJ212 turbo?

This will vary with the marinization and vintage of the engine, but in general, at or near sea level we see approximately the following full throttle rpm's…

Ford 351/Chevrolet 350      2.4T   4100 - 4200 rpm

Chevrolet 383 “Stroker”      3.4     4000 rpm

Chevrolet 6L                        2.4     4450 - 4500 rpm

Chevrolet 6L                        3.4     3900 - 4200 rpm

Ford 460/Chevrolet 454      3.4T   4000 – 4100 rpm

Chevrolet 502                      3.4T   4200 – 4300 rpm

Chevrolet 502                      4 T     3850 rpm

Chevrolet 8.1 375 hp           4 T     4020 rpm

Most of the boats we see achieve an acceptable cruising speed at 2800 to 3300 rpm but this will vary widely the individual boat and load.

If you’re operating at higher rpm’s expect to see a significant drop in rpm’s and power.  You will loose roughly 3% of your horsepower for 300m (1000’) in altitude.  If that’s the case you may need to use a smaller impeller to achieve as reasonable rpm.

Here is an article about the HJ212 and High Revving engines.

How’s the fuel economy?

Boat builders who have installed HJ212s in aluminum boats where a sterndrive counterpart exists have reported similar fuel usage between the two versions.  Because boats designs differ dramatically its possible that you could get slightly better to slightly worse economy, depending on the situation.  In general, a waterjet is more efficient on lighter, clean running vessels.

Can the 212 be used in saltwater?

Sure, just wash it down thoroughly with freshwater when you’re done.  However, the HJ212 isn’t designed to be moored in saltwater for extended periods.  If that’s what you intend to do you should consider an HJ213.  It’s possible to add some of the HJ213 additional protection to the HJ212, but not all of it.

How about diesel engines, can they be used with the HJ212?

As with the question regarding saltwater usage, the HJ213 is really the best way to go if you need or want a diesel.  It certainly can be done but we would have to look at what was proposed and get the application approved to be sure that there wasn’t a problem.

Diesels present some unique problems that would have to be addressed.  At a very minimum a few changes would have to be made to the jet and a suitable torsional coupling would be needed.  Beyond that the impeller range of the HJ212 is not as extensive as that of the HJ213, a suitable impeller may not exist.  All that said there are small, high rpm (3300-4100 rpm) diesels from Yanmar, Volvo, Cummins and Steyr that theoretically could be used on some occasion.  Larger, slower turning diesels would require a larger jet.

What is the difference between a HJ213 and an HJ212?

Both jets are the same size and produce the same thrust from the same horsepower.

However, the HJ212 was intended to be used primarily with gasoline engines on recreational or guide boats used primarily in fresh water.  The HJ213 is the commercial version, it has more anode protection, a heavier maninshaft and thrust bearing, some different alloys and power hydraulic reverse.