Yamaha Genesis 120hp engine

[serge5694]

hello
I added a radiator for extended fixed point without overheating tests.
I think the setting is OK, slowed to 1,000 rpm allowing a gentle stop, acceleration gives no problem.
I just remove the gear box, I'll just make a hole for better lubricate the rear bearing of the propeller shaft and another between the bearing and the oil seal to crank out as the oil pressure rises slightly , if everything is OK.
warm start or cold with the original starter is good, I removed the electric heater.


https://www.youtube.com/watch?v=txmnyYkkdds]moteur ulm yamaha - YouTube

 

[j bird]

:boink::focus:

 

[NoWingsAttached]

I tried to keep my engine as stock as possible, they are legendary in the sled world for being tough bullet proof engines and I wanted to modify it as little as possible. I left the carb heat on and never thought about it again. Never had issue with it either.

Oil filter is cheap, its the same one that fits yamaha R1 sportbikes. They don't cost much and I changed oil every 50 hours.

I've been using Mobile 1 synth, 5w-30. Change oil every 25 hours, change filter every 50 hours. Manufacturer suggests change filter every other oil change, but if I was going to 50 hours for an oil change I would not skip the filter.

Plugs and filters are all available everywhere, even places like K-Mart, Target, and WalFart.

 

[NoWingsAttached]

Thanks to all for your feedback,
I may end up using the stock panel as it would be plug-n-play. However, I find it a bit bulky and too much useless information. I will look into Tinytach (I am already using it on the Rotax 670), or an alternate tach with adapter for coil over plug DIS ignition.
What about the carb heat? The Aventura is flown only during the summer, do I need the coolant through the carbs? I read on this forum an engine out due to fuel vapor lock (GyroRon?). Perhaps a switch for the electric carb heat on demand is preferable?
Another question: what type oil filter? Yamaha OEM or automotive substitute?
Aventura Mike.

First - I like the stock tach/instrument pnl for a number of reasons. I took the stock tooth-counting speedometer sensor off the sled and mounted it at the ring gear to give rotor RPM using the MPH readout on the Yamma tach I just have to mentally calculate what the speedo shows times 6. Example, the speedo shows 10, RRPM = 60 and I can start moving the stick back slowly. It shows 20, I am turning 120RRPM and can roll out if i want. It shows 23, we have almost 138 RRPM and can go instant half throttle for take-off roll. It shows 28, I release the rotor clutch, at almost 180 RRPM, to save wear on the little 6-rib PTO belt.

Finally, the Yamma tach gives engine sensing readouts including over-heating and low oil. This is NOT useless.

One last thought: If the panel goes blank, that tells you you have an electrical failure, a short, or a charge system failure. Your tiny tach won't do that - it will go on working and you will be oblivious to the danger. This happened to me. (I was three miles out from my airport but the Yammamamma didnt' skip a beat - it is carbbed. Had it been EFI I would have been looking for a place to land in a cow pasture quickly. Instead, the carbbed engine kept running, since it doesn't need the brain box nor the charging system to deliver fuel and fire the plugs. The plugs are powered direct from the magneto to INDIVIDUAL coils fitted on the spark plug boots. If one coil goes bad, you only drop a single cylinder, the motor will continue to run and provide sufficient power to land safely - especially with the YG4-cylinder. This is why I am not a proponent of EFI aircraft conversion engines of ANY type. They are an unplanned landing looking for a time/place to happen when the brain box dies. EFI is unnecessary on this carb-heated engine, and it is actually only useful if you plan to climb more than 5000 ft from your take-off MSL.)

You really DO need to leave the coolant heating on the carbs. You can ice your carbs when ambient temps are 70F. The electric carb heat is not necessary, it is only for pre-start and extreme cold conditions.

Oil filters are available everywhere. I buy the ones in the black box.

 

[serge5694]

hello

this forum in French you can see pictures of the different stages of transformation of genesis 3 cylinder, from page 11.
http://www.forum-ulm-ela-lsa.net/viewtopic.php?f=439&t=1926&start=150

 

[dinoa]

Very neat solution and nice machining.

Dino

 

[RICK MARTIN]

Jason, Racer, Greg,

Can you guys please tell me your coolant temp characteristics?
Static, normal cruise, full throttle climb out, any spike on shut off etc.?

Thanks,

 

[serge5694]

Jason, Racer, Greg,

Can you guys please tell me your coolant temp characteristics?
Static, normal cruise, full throttle climb out, any spike on shut off etc.?

Thanks,

I'm just testing the fixed point, full gas 90 ° celsius

 

[NoWingsAttached]

I can't help you out there, I only rely on the idiot lights on the stock Yamaha tach/panel to tell me if it gets too hot - which has never happened. Some day I will install a water temp gauge, cuz I like lots of dials and readouts and gadgets, but for now I have no need for it.

 

[RICK MARTIN]

Serge,

What do you mean by "fixed point"? Do you mean with the machine tied down on the ground as in a static test? If so, 194 degrees Fahrenheit sounds a little on the high side to me.

Thanks,

 

[serge5694]

Serge,

What do you mean by "fixed point"? Do you mean with the machine tied down on the ground as in a static test? If so, 194 degrees Fahrenheit sounds a little on the high side to me.

Thanks,

yes my motor is mounted on a floor stand (see my different messages past), the max I've had more than 30 minutes after full throttle is 90 degrees celcius, normal flight the temperature is always lower.
it would be boring to know what temperature the engine is considered too hot by yamaha indicator.
for information, I measured the opening calorstat original 70-75 ° C, so I think 90-95 ° max is a good temperature.

 

[RICK MARTIN]

Thanks Serge,
Yes, I understand that the temp will be higher in a static run up.
I meant to say that I thought 194F would be a little high for an in flight reading.


The only figure I've seen posted for an in flight reading is 180F. That is exactly what I'm getting if my equipment is accurate. I am just looking for some confirmation from multiple sources that I'm comfortably in the ball park.

 

[Racer]

I am also confused on what you mean by Fixed point.
Mine runs near 165 degrees all day long no matter what I am doing.
The thermostat keeps it at the correct running temp.
190 is the highest that I have ever seen it.
Todd

 

[NoWingsAttached]

hello
I added a radiator for extended fixed point without overheating tests.
I think the setting is OK, slowed to 1,000 rpm allowing a gentle stop, acceleration gives no problem.
I just remove the gear box, I'll just make a hole for better lubricate the rear bearing of the propeller shaft and another between the bearing and the oil seal to crank out as the oil pressure rises slightly , if everything is OK.
warm start or cold with the original starter is good, I removed the electric heater.


https://www.youtube.com/watch?v=txmnyYkkdds]moteur ulm yamaha - YouTube

I still have the photos you sent me of the three-gear PSRU you built here. What is the manufacturer make and model of the sprag clutch you have the prop mounted to? I am really happy to see the gearbox working! Glad to see you are testing and breaking it in on the static mount.

I only just started to look into what the FW guys want for an engine conversion, and now your gearbox makes perfect sense. They all want the prop as high up as possible!

I've decided to come out with two redrives this year: Pusher, which keeps the prop near the middle of the engine COG, and tractor, which provides best cowl visibility and places the prop 4 inches higher. Holding my breath. Turning blue...working night and day, even on Christmas Day...getting closer...

 

[NoWingsAttached]

One of Serge's Videos - Do Not Miss This

One of Serge's Videos - Do Not Miss This

This is interesting, How did he get the gears and axles to stay in place with the face plate removed???

https://www.youtube.com/watch?v=veEHpMXXelg

 

[RICK MARTIN]

Thanks for the info Todd. I think the stock thermostat was set for 172F. does that ring a bell?

Jason, what temps are you running?

 

[serge5694]

I still have the photos you sent me of the three-gear PSRU you built here. What is the manufacturer make and model of the sprag clutch you have the prop mounted to? I am really happy to see the gearbox working! Glad to see you are testing and breaking it in on the static mount.

I have not instaled free wheel clutch, only a torque damper.
the middle gear is mounted on a stationary shaft with a needle bearing. the propeller shaft is mounted with double ball stowed, it is only possible to run without power when the faceplate is removed
I studied and manufactured all the parts, even the gear with a friend
90 ° C are achieved with only a small radiator, with the largest temperature is regulated by the calorstat

 

[JEFF TIPTON]

Greg; plexiglass coverplate.

 

[Jason O]

Hello,

I no longer own the airplane and don't remember what it was running at. I would take the stock temp sensor that turns on the dash light, put it in a pot of water with a thermometer and put a multi meter across it. Take note of the water temp when the sensor kicks off. That would be the temp that Yamaha sees as dangerous and I would use that as a reference.

FWIW
Jason

Thanks for the info Todd. I think the stock thermostat was set for 172F. does that ring a bell?

Jason, what temps are you running?

 

[RICK MARTIN]

Thanks Jason. Good advice as usual.