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Comment by John Austin on September 30, 2019 at 1:30pm

I have a Jab 3300 so I am highly biased!  :>)  Early Jab engines had a history of problems that haunts their reputation to this day. However, they've been building them for nearly 3 decades and currently are on their "4th Generation" engine with very positive user experience reports so far.  My engine was late "2nd generation/early 3rd generation" or sometimes called a "late hydraulic lifter" engine.  It has been very reliable for 600+ hrs and it, Rotax, and UL are the lightest engines available.  I see the advantages of the Jab as having simple direct-drive, light weight, and a simple gravity-fed fuel system with no return lines or header tanks, etc. necessary.  It has solid-state magneto ignition so once it starts, as long as it has fuel and air, it will continue to run.  It produces 120 hp at max rpm.  The biggest downside is it is a 6 cylinder air-cooled engine, so meticulous attention must be paid to cooling airflow, especially in a high-drag airframe such as the STOL 750.  However, I average CHT's about 275F in the summer, so no problem for me!  The 4th generation engines have even more cooling fin area and should be even easier to cool.

The UL is also direct-drive, light weight, and air-cooled 4-cylinder with 130 hp.  It has the advantage of a modern ECU-controlled fuel-injected engine, so it's likely more efficient.  However, it is dependent on the ECU to keep the engine running, but the ECU is very reliable.  However, the modern fuel injection and extra 10 hp makes the engine far more expensive than the Jab.  I "think" the Jab is still under $20K - a bargain compared to Rotax or UL.  But like I said, I'm biased! I also think the Jab is best-sounding engine there is, except for a Merlin!  ;>)

John

N750A

Comment by Buzz Air Flight Academy on September 29, 2019 at 4:10pm

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