I have a few extra Evolution TPS engines from Hangar 9 P-51 Mustangs that I don't fly anymore. I also had a new Hangar 9 Tango in need of an engine. Instead of putting out the $'s for another engine, I decided to try to get one of the TPS engines to respond as well as the Evolution 46NX I use in a Twist 40.
I removed the flywheel from the TPS engine and pressed the outer weightof the flywheel off of the aluminum spool piece. This was easy using abench vise and some washers. I replaced the aluminum spool piece to make up the space on the drive shaft andmounted the spinner/prop inthe normal set-up.
The first test flight of the Tango with modified TPS engine was very rewarding.The engine responded to throttle input aswell as the Evolution 46. The idle was just a smoothas the idle with the intact flywheel.

Anyone know of any problems that mayoccur by running one of the Evo TPS engines without the flywheelweight?

With the research I haveperformed, the TPS enginespecifications are nearly identical to the 46engine. If this works out, you shold be able to save a significant amount of moneyif you have one of these TPS engines not in use.The difference in retail pricing between the TPS and the 46NX is $40.

The difference between the NX .46 and the PTS in displacement is so small that you'll not notice.

Throw an 11x6 prop on the PTS and it comes into it's own in terms of power.

The flywheel helps smooth out idle problems, particularly when the engine is new, but once it has been run for a while, you can eliminate the flywheel without adverse effects.

IMHO the biggest thing to worry about with the PTS are the limiters.

You should REMOVE the blue collared limiters altogether ( not just pull the pins! ), then tighten up the clips to prevent the needles from "walking".

Once done, you'll have a nice and reliable engine.

You can also pull the baffle from the muffler to obtain a couple of hundred more RPM's ( more power ) too.

Both you guys are driving me nuts making me think of that stupid movie "Office Space" and the blasted TPS reports. It's a "Progressive Trainer System" or PTS

Wow...

I must have had that movie inadvertently in mind when I wrote that.... the fax/copier versus baseball bat scene...

Just wanted to make sure you got the memo about using the new cover sheet on those TPS reports... Yeah, that'd be great.

PTS stands for Progressive Trainer System. TPS stands for Trainer Power System.

The RTF is a PTS, the engine on the RTF is a TPS.

"Overview:

If you're just getting started in the hobby or you're planning to teach a new pilot, count on Evolution's unique Trainer Power System for the most beginner-friendly starting on the planet. It's so convenient and easy to use that we include one in every Hangar 9 trainer. Everything you need comes in one convenient, affordable unit. Engine, spinner, prop, glow plug - it's all there and designed specifically to get a beginner pilot into the air quickly and easily. Just 2 or 3 flips of the prop, and it's running smoothly and quietly."

bigedmustafa:

Ok so we DO NOT have to submit TPS reports with cover sheets?

Yes, I am trying to address the Evolution Trainer Power System (TPS) or part number EVOE100. 

Ran the engine again yesterday at dusk with touch & go's with no problems.  I will need to work on the tuning on the low speed. 

So far I have left the limiter on the low speed because it makes field adjustments much easier, once I get the adjustment within the limit stops.  I have found that the low speed adjustment is very sensitive.  You can go from lean to rich with very little movement (1-2 hour or 1/12th to 1/6 of a turn).

I have not tried to remove the muffler baffle.  Is that straight forward?

If you can get a good tune within the stops, there is no reason to remove the limiter.

Typically however the engine requires a setting that is just slightly beyond the limiter.

More important is to prevent the "walking needle" problem.

The limiter collar particularly on the low end, tends to move when the plane is in flight and/or when the engine is warm during a run.

This can and will cause all sorts of problems, until you eliminate the walking.

The easiest way to do it is by putting a piece of exhaust tubing over the needle to hold the clip tight against the detents.

Another method is to remove the clip, and tighten it to add more resistance to needle movement, before re-installing.

Re; Muffler baffle.

Yes.

Open muffler, remove baffle, put it back together with a bit of loctite applied.

You need to make sure to use the new cover sheets for the TPS reports. I don't know why this is so hard, it was all explained in the memo!

Was the memo sent by FAX?

I guess I missed the memo on the TPS thingy

Ok Bigedmustafa, I found the "New" TPS report cover sheet here...

[link=http://chrisglass.com/journal/downloads/TPSreport.pdf]TPS Report Cover Sheet - Click me![/link]

Hopefully that is the RIGHT one!

TPS reports! That's my stapler! Yall are making me bust a gut

Just dont burn this place to the ground...

The last time there was cake I did not recieve a piece...

I'm gonna set the building on fire.

Yeaaaaaaaaaah, I'm going to need you all to come in to work on Saturday. Okay/ Greaaaat.

Here ya go Milton......