lozza1965

Thank you for the quick reply, I have no idea why they are so bloody messy, mates fly other makes of radials and have very clean running engines, just wonder if the cylinders are not burning the oil off, not getting hot enough, all I know is its really screwing the painted solartex finish.

Timbers

My Feedback: (3)

Does yours take a few mins to come up to full RPM? Mine usually requires at least 3-4 minutes of revving it up on the ground before the bottom cylinders light. It makes a lot of black gunk during this phase for sure.

I seem to have the blank gunk issues on my Saito radials as well.

lozza1965

After about a minute or so I'm up to about 5400 iirc

TJPro351

My Feedback: (8)

I have a UMS-150 on a TopRC P-47. After break in (40:1) and running a Biela 23x14x4 prop using a APS pump, what RPM's should I look for at full throttle when tuning?

rgoinbroke

Next spring I will have my TopRc FW190 flying with the UMS 5/150. Be able to give feed back then on rpm. Meanwhile would like to know the performance you are obtaining. Thanks!

Chris Nicastro

My Feedback: (3)

Is anyone looking to buy a 150/5? I have a new one and I’m not going to use it because I’ve decided to build a CARF Corsair with a Valach 250 instead. This engine has been bench run only for three tanks and it’s ready to go. I think it’s a great engine as far as I can tell so far and it sounds very healthy. Let me know if interested

Chris Nicastro

My Feedback: (3)

That’s the exact same build I was going to do! I picked up the VarioProp 3 blade 32i set up and three blade spinner for it. Then plans changed and I’m working on a CARF Corsair so I’m selling the TopRC FW and UMS engine now. I can use the prop hub on the Corsair and I plan to come back around to an FW later on.

Hyjinx

Black crap. We have a 125 running redline and one running Amsoil Dominator. Both push black crap identical.

​​​Tub o towels takes it right off. Small price to pay for that radial realism lol. Ever even close to a full scale radial ? Even more black crap.....

Second UMS 125 at our field running great right out of the box......

Chuck Yeager

Dear UMS fans,

I have just purchased a UMS 150 for my PZL 104 Wilga project.
Do you run it with an electric pump setup in your planes or just regular out of the box?
I heard that they are quite tricky to tune without a pump.

Thank you in advance for your feedback.

Hyjinx

Here is the second Phoenix Waco online at our club. Mine is the same but has an earlier light kit.
Sorry. Can't add link to video site won't allow upload..

Maxam

My Feedback: (62)

Chuck, get the pump!

Chuck Yeager

Dear Maxam,

I have already purchased Hacker PowerFuel Rx V2 and I should get it within about 2 weeks.
Do you haver any reccomendations on the pump settings? The manual only says that the it shoud be set up within 30%-60% range depending on motor size.
Any ideas where UMS 150 should sit within this range?

Thank you for your time and support.

marksp

My Feedback: (9)

Curious which Wilga?

Chuck Yeager

Tomahawk Aviation 3.2 meter

Maxam

My Feedback: (62)

I am not familiar with that brand of pump. Start at 50% power and see if you get linear response as you SLOWLY accelerate from idle to full power. This is only after the engine is well broken in.

Hyjinx

Hey Chuck.
This 125 is running a linear curved pump.
Mine runs the same with the same pump running at a constant 5 volts. Experience says the curve is not mandatory. The only reason anyone has given is pump longevity. The engine will run well at any pressure. The walbro meters the fuel. Not the supply. The excess is returned to the tank. Keeping it simple.

5 volts.

Hyjinx

[QUOTE=Hyjinx;12790390]
Hey Chuck.
This 125 is running a linear curved pump.
Mine runs the same with the same pump running at a constant 5 volts. Experience says the curve is not mandatory. The only reason anyone has given is pump longevity. The engine will run well at any pressure. The walbro meters the fuel. Not the supply. The excess is returned to the tank. Keeping it simple.




This one is mine running constant line pressure at 5volts.

Chuck Yeager

Thank you very much for your support

Hyjinx

Your welcome Chuck. I started this thread to try to discern the quality and engineering of the UMS redesign of the original Seidel radials (a few generations ago). A lot of helpful info has resulted. The redesign and metallurgy seen to be holding up well based on responses from owners. Welcome to the family!
Aaron-

Carlo Vangompel

[QUOTE=Hyjinx;12790391]Well, that motor runs fine.
I also mounted a PowerFuel RX V2 hacker on my UMS150, and tested it out today but seems that the motor runs even worse than before, finally it stops running.
When I switch of the pump, rpm increases. It runs horrible with the pump.
I tried on low and high speed using a switch, but there is no difference.
Any idea what could be wrong?

Carlo

Maxam

My Feedback: (62)

Carlo, when using the pump you must screw in the idle and high speed mixture adjustment screws otherwise you will be too rich. Usually about 1 and 1/4 turns out from all the way in. -Tom

Carlo Vangompel

thanks, I will try it this week. I also noticed to use 5V. I Have 7.4V Liion batteries but will test with 5V

Hyjinx

The pump speed is contingent on voltage between 5-9 volts. That's why I leave mine at 5. Slowest rpm that won't starve the electric brushless pump motor. Toms experience mimics mine on needle adjustments more or less. I returned mine yesterday to factory settings and it tuned easy and fast with a bit of adjustment on both needles toward lean .
To the group...
Both mine and my club mates 125s are both experiencing partially stuck exaust valves on cold start and between runs when up to temp. They are not consistent cylinder wise but it seems always and only on the exhausts. We are running different oils (redline and Amsoil). Wondering if the factory fit between the valve stem and guide is/are too tight. Or a carbon build up on the stem?
Anyone else chasing this bug?

Maxam

My Feedback: (62)

Sea Foam, 2 oz/ gallon? This prevented stuck valves for good.

planenutzz

what an excellent suggestion!!