ORIGINAL: 74SEVEN7
Hi Bill, its nice to know that at least ONE person read my Enya articles ! Just to set the record straight though, when I said - "I recommend that anyone blah-blah", I was actually talking about the ball raced versions of the Enya 19-V & VI, not the plain bearing jobs. That's not to say that the bronze bushed 19's aren't great engines - they are (well, ALL Enya's are !). Its just that from an engineering point of view, the twin ball raced Enya 19 is a delight. The only drawback with the 19 BB is, its a bit heavier than the plain bearing model, and it doesn't really produce much more power, so unless you need a bit of weight up front (such as in a Barnstormer)
you'd be better off with the plain bearing. Speaking of Enya articles too, we (that's me and two other guys) are working on producing a
more comprehensive and cohesive set of articles dealing with the Enya brand, to improve on my somewhat disjointed earlier efforts.
Finally, the original author of this thread (Bass1) showed us a photo of HIS Enya 19, which is actually a 19-IV. These earlier models are even better suited to C/L stunt work, as they are old technology with a longer stroke than the V or VI, but they need a wider spacing between the engine mounts to fit 'em in. I hope I can now prevail upon Colin Weaver to extoll the virtues of his Enya 19-IV ! Cheers, BOB ALLAN
Can't resist! Here are my thoughts on this lovely engine. (Note, this is very biased material - I have never met an Enya I didn't like!)
I have yet to fly a 19-IV, and the one I'm running now it seems to need more running in time before it is ready to go.
BUT - I have been bench running one in an effort to get it broken in and ready to go in a model.
My initial impressions were that it was cranky and hard to start, with a tendency to bite back or sit there oscillating. At that stage I was running a Taipan 9x4 on it. I then noticed that my example - from eBay - despite appearing to not have been run in had two problems. Firstly, the spraybar was non-standard. Secondly, the steel venturi insert was missing, leading it to have poor fuel draw and a distinct tendency to snuff.
After replacing the NVA with the correct one for a 19-IV, and fitting the venturi insert from another 19-IV in my collection, I was able to get much easier starting & tuning. I then noticed a tendency to spit fuel out the venturi when running rich. Altering the spraybar hole orientation from straight down to sprinkling rearward cured most of this.
The next thing I did was experimented with different plugs. In common with my 19-V, which I have now flown, it seems to like moderately hot plugs. Enya #3 and OS A3 give much better runs & behaviour than cooler plugs. The 19-V is more tractable in this area, the 19-IV tends to snuff randomly when rich if you run it with an OS#8 or equivalent, but put an OS A3 or Enya #3 in and it keeps right on going. Nitro makes absolutely no difference except for tolerance of rich settings. NO observable difference in peak performance between 5% nitro fuel or straight 75/25 fuel. The only difference is less tendency to stuff when rich with 5% nitro.
After a bit of breaking in, I did some tachometer readings. There were some real surprises here. The 19-IV is definitely a "torquer" and displays diesel like operating characteristics. I started off with a 9x4 Taipan, on which it was a bit snappy/balky. Brief bursts of peak would max out in the 11,200 - 11,500 RPM range, which I thought was low. The 19-V will happily do 12,000 on the same prop. I then thought "long stroke engine - try a bigger/heavier prop". What a difference! The optimal prop to date is the Bolly Clubman 9.5x6, on which the 19-IV displays awesome diesel like torque and power, and equals the PAW 19BR! Steady, rock solid 10,600 RPM on 9.5x6 for a huge amount of thrust. To put this in context, that calculates as about 0.35bhp (well over Enya's claim), is 500 RPM MORE than my two plain bearing PAW 19s, 200 more than my mate Steve's PAW 19 BR, and the exact equal of my Saito FA-30S four stroke on the same prop. The verdict, for best results use a 9x6, 9.5x6 or 10x4 on the 19-IV, use a smaller prop like 9x4 and you're throwing away half the performance of the engine.
My impression is that the 19-IV is a damn fine engine, and a direct glow equivalent to the lovely PAW 19 which is my favourite diesel. The two engines are basically interchangeable - I would not hesitate to put a 19-IV in a plane designed for a PAW 19.
cheers,
Colin