Help! I need to ask for insights on this...today my OS 160FX with the VP-30 pump ran for several flights real good, then it got testy on me, and got to the point that on the ground while running it up for another flight, the engine would run fine at full throttle, then sag, run slow, run real fast again, just all over the place with no consistency. I did not take off, needless to say. I had not touched the pump adjustment in over a year, and all I was doing was changing the high needle setting due to slightly warmer weather. Maybe something got in the carb throat, but do you think these can also be symptoms of the pump going bad for some reason? It is only two years old and doesn't get lots of flight time, perhaps 30 flights each year. When I got home, I decided to just do what my son did on his Extra with the very same engine and muffler, and that is use large fuel tubing and no pump. His runs and starts like a charm on the first or second flip all the time, and never dies in the air. It's a quick change and I am going to see if that works. If so, the pump went bad or way out of adjustment on its own, since I never touch the thing. What do you think might have happened? I can add that I was at the bottom of the fuel jug today, but the gas sure looked clear to me. Thanks for any insights you might have. Jon

The OS 160 does run better with the Perry pump than most engines

You need to isolate your problem with one change at a time.

Try different fuel

Try no pump

Do you use fuel with castor? The diaphragms don't last forever or sometimes can get stuck. You can rinse it with alcohol, making sure you go in the direction of fuel travel.

I have not had luck with the Perry Pump, but I'm running an OS 120 and think the pump puts out just too much fuel for that engine.

Thanks. Ihave been running the same 5% Coolpower on this engine for two years and it has liked it fine, so I don't think fuel is the issue. I am going to try no pump per my post. But I am also changing to the slightly larger ID fuel tubing like my son uses on the same engine and muffler. Might go to the field tomorrow to just run the new setup, even if it's windy and I can't fly. I'm anxious to resolve this latest challenge. Jon

HOORAY!!!!!!  I test ran the engine just now, without the pump, and with the large ID tubing, and it ran on the ground just fine.  Before running it, I reset the mixture screw per the OS manual, and I started the engine with the high needle opened about 2 3/4 turns.  Used the same 5% Coolpower as always for this engine.  I primed it about 8 turns of the prop while holding my palm over the Slimline twin ports.  The engine started on the first flip and ran steady but rich.  It ran about 5 minutes as I turned the needle in to about 2 turns open.  Still running slightly rich, now I will take her to the field to fine tune and see if she is fine in the air, BUT the main conclusion is that the Perry Pump VP-30 went bad in less than two years and only about 50 flights.  That blows.  At least I isolated the problem and can fly again.  Thanks for the suggestions offered.  Jon

the statistics really seem to be showing that the Perry is more problems than it's worth. I am working on switching to YS exclusively.

I'm glad you got your plane working

Is your tank at firewall or CG?

i dont know the lifespan of a perry vp30. i have one that is a few years old and still working nice. One thing i know is that with the vp30 the needle settings is more important when the weather changes from day to day. 2-3 clicks too rich on high speed needle and the engine bogs down and quit. Most reliable and predictable engines in my book are fourstroke engines without any pump.

If everyone who used a particular product reported their results here, we would have a real consensus of how they functioned. The ocassional gripe or praise post doesn't constitute a consensus though. </p>

</p>

Terry in LP</p>

Very well said!</p>

All i know or remember is that all the twostrokes i have had have giving me deadstick maybe once a year or so and the pumped engines be it a YS or a twostroke on vp30 giving me deadsticks too maybe twice a year or so simply because i didnt care to adjust them more accurately at that time. Saito andOS fourstroke nonpumped engines have never quit on me that i can remember. I think it is good information for other readers.</p>

Twostrokes on vp30more or less needs adjustments every day you go out to fly, atleast the main needle does.</p>

IJust meant I've been doing a lot of related research - questions, polls, PM's, about running a Perry pump, and while there are some happy users, most seem to have problems if not totally hate the device.

Two stroke engine carburetors are simply not designed to have pressurized fuel forced upon them.

Check your bearings. I have changed the bearings in my OS160 twice. The original steel and the replacement steel bearings rusted out after approximatly 35 flights. Prior to changing the bearings I could not get a consistant runing motor. I believe that the bearing were pitted and causing vibration which in turn caused foaming of the fuel. Im now using ceramic bearings andhave had more than 40 flights. One dead stick due to worn out OS "F" glow plug.Main needle 2 1/4 turns out. (slightly rich) Perry pump at factory setting. Coolpower 15%. 18 x 10 APC.
Beautiful.
Kiwipaul

Paul,


Fuel-foaming is a non issue.
The real bugger is the deflection of the clunk off the tank bottom and walls (when the tank isn't properly isolated from airframe vibration); which in turn results in ingestion of air, bubbles, fuel vapor and other gaseous matter, into the fuel-line; instead of liquid fuel...

'CruelPower' is a sorry excuse for fuel and it is the cause of the rust in your bearings (or the non-prevention thereof) ...


Use only fuel that contains a reasonable amount of castor oil... In North America, most fuel manufacturers leave you no choice...

Dar, is CoolPower adequate if one adds a bit of castor to it?

i buy fuel at Lindinger & they don't seem have much else...

Quote:

ORIGINAL: vasek

Dar, is CoolPower adequate if one adds a bit of castor to it?

I buy fuel at Lindinger & they don't seem have much else...

Vasek,


But then it is no longer original CruelPower, is it?

For me, if the LHS does not bring the fuel that I need (maybe for reasons of not wanting your engine components to last too long...), is a good reason to prefer a different hobby shop...

IMO it is always a very good idea to add castor oil to fully syntetic fuels. It never hurts anything and adds lean-run and rust protection.

Not everybody has the luxury of selecting between several hobby shops. We had 2 here for about 2 years and life was great. Not to mention the prices suddenly got better than ever. I miss the one that had to shut down because of management problems. They were 10 minutes away and I remember ruining a long sheet of covering one night and they were open at 10PM with what I needed.

Gentelmen.
In my earlier messageI mentioned vibration as the cause of fuel foaming. The foaming is inside the motor not the fuel tank. I have not seen airbubles in the fuel lines at any time weather bench running or in the plane itself.
Glow fuel weather it be Cool Power or Omega will attract moisture from the air. All motors have some fuel resdue left behind even when run dry of fuel. That is why the bearings rust out, minutly at first but will get worse asthe motor is used.
Myself and two friends have had this problem with the OS 120, OS140RX and myself with OS160FX. Changing to stainles or ceramic berings cured the eratic tuning problem.
Today I had 4 flights and like I said before.....beautiful
Kiwipaul</p>

Quote:

ORIGINAL: kiwipaul

In my earlier message I mentioned vibration as the cause of fuel foaming. The foaming is inside the motor not the fuel tank. I have not seen air-bubbles in the fuel lines at any time weather bench running or in the plane itself.

Paul,


The amount of fuel sucked inside your engine's crankcase, while it is running at full throttle is ~ 0.0133 cc (0.000476 oz.) per cycle...
It is not left waiting there and is delivered into the combustion chamber
This quantity is not sufficient to be 'churned' into foam.

At low-throttle, some fuel will 'puddle', but the vibration level is much reduced...


Your statement is not realistic.

Quote:

Glow fuel; whether it be Cool Power, or Omega, will attract moisture from the air. All motors have some fuel residue left behind even when run dry of fuel. That is why the bearings rust out, minutely at first, but will get worse as the motor is used.

Fuel that contains a sufficient amount of castor oil, will have enough of it thoroughly coating the bearing races and balls; thus preventing their contact with the moisture accumulated by the hygroscopic methanol.
Running the engine dry at the end of EVERY flying day, will reduce the amount of raw methanol left in your engine to a bare minimum, so, there will not be 'washing' of the tenacious castor oil from the bearing surfaces either.
CoolPower oil, Klotz Techniplate and most other American made synthetic lubricants, simply are not endowed with the strong tendency of castor oil to remain on metal surfaces.

I never had to replace rusted bearings, in any engine that I ever owned - I also have never use any CoolPower (or any other all-synth), for over 16 years...
One of my engines has over 150 hours and original 52100 steel bearings. No rust!

See the connection?

Quote:

Myself and two friends have had this problem with the OS1.20AX, OS1.40RX and myself with OS1.60FX. Changing to stainless, or ceramic bearings cured the erratic tuning problem.

This is purely circumstantial... Stainless steel bearings do offer greater resistance to corrosion and silicon-nitride balls cannot rust...

Besides, for some reason, OS engines seem much more prone than others, to rust in their bearings.

what is the % of oil content of CoolPower?

Vasek,


CP has 17% oil; all of which is Omega™ Cool Power synthetic lubricant; glycol base I believe.

Dar,
if my calculations are correct, to bring the total to 20% oil i'd have to add 114ml of Castor to 1gallon (?)

Yes, Vasek.


That would be roughly 3% castor and a total of 20% oil... Ir rather 20/103 percent.

For a two-stroke engine, I would prefer more castor oil, though...