Building the JU-02 gas producer

[racket]

Hi Anders

When we checkout the specs sheet for the pump www.proconpumps.com/content/Series%205%20Pump_spec.pdf it should be flowing more than enough on 12 Volts.

Did you do a "no pressure" flow rate to determine if theres wear causing the loss of flow at higher pressures ??

That stepup power supply is "interesting" , I wonder how they achieve it , but if it spins the pump fast enough for >9 lpm , then you're ready to go :-)

Cheers
John

[Johansson]

Dec 4, 2018 5:10:23 GMT -5 enginewhisperer said:

I'd be more worried about the step up converter blowing up mid run than a higher powered motor breaking.

They're also fairly likely to not actually meet the advertised specs, and might not be very efficient so you'll pull a lot of current from the battery.

With the 4bar safety switch apparently working I am not worried about a possible pump failure, and I will have plenty of run time to find out if it works or not before it is time to hit the race track.

For the cost of 80 dollars I think it is worth a try, I have a 60Ah LiFe battery on the bike so plenty of capacity even if there are losses in the converter.

Dec 4, 2018 5:12:07 GMT -5 racket said:

Hi Anders

When we checkout the specs sheet for the pump www.proconpumps.com/content/Series%205%20Pump_spec.pdf it should be flowing more than enough on 12 Volts.

Did you do a "no pressure" flow rate to determine if theres wear causing the loss of flow at higher pressures ??

That stepup power supply is "interesting" , I wonder how they achieve it , but if it spins the pump fast enough for >9 lpm , then you're ready to go :-)

Cheers
John

Might be the motor that is a bit weaker than adverticed, since the pump shaft is sealed in the housing I can´t measure the rpm´s while it is running.

Nope, I didn´t think of doing a free flow test unfortunately. But knowing that 24v gives the flow I want I don´t think it is worth the effort doing any more tests before I have the 24v feed to the motor.

I´ll order the converter and see how it performs.

Cheers!
/Anders

[turboron]

Anders, my solution to the oil viscosity drop with temperature was to add a second oil supply pump. I switch on the 2nd pump when the oil pressure falls below 50 psig. This could be done with a pressure switch. I am planning to use an Arduino PWM controller during my control development. It may not be a good solution for your bike due to space limitations.

Thanks, Ron

[Johansson]

Dec 4, 2018 11:08:06 GMT -5 turboron said:

Anders, my solution to the oil viscosity drop with temperature was to add a second oil supply pump. I switch on the 2nd pump when the oil pressure falls below 50 psig. This could be done with a pressure switch. I am planning to use an Arduino PWM controller during my control development. It may not be a good solution for your bike due to space limitations.

Thanks, Ron

Hi Ron,

That is another way of doing it, pretty neat if there is room for a second pump.

I have high hopes for the 24V pump feed, it became a very different beast with twice the voltage. I just hope that I wont have to wait forever for the controller to arrive.

[Johansson]

I test ran the engine just now with 24v to the oil pump, no signs of pressure drop so that seems to have fixed it. Unfortunately something happened inside the engine as you can see, I have to take it apart and check the havoc but the rubbing indicates that I have a bit of work ahead of me.

All part of the R&D, I´ll keep developing it until I can run it flat out for as long as I want.



Cheers!
/Anders

[Deleted]

Don't have words

[dan]

I hope your wheels are salvageable Anders. Considering the kinetic energy involved, that was quite a controlled shutdown.
Really glad to hear your oil pressure problems have been solved.
Best of luck
Dan

[Johansson]

No worries Andrew, I am sort of thrilled that I finally got the darn oil pressure sorted. Plus I am glad to have found a flaw in the design, I´ll just have to figure out what it is and fix it and then hopefully the engine is 4 bar proof!

Thanks Dan, as soon as the kero smoke has cleared in the workshop I will disassemble the engine and see how extensive the damage is.

[elventu]

Just watched the video on YouTube.
I'm sorry for the work you must do now, but for sure, it is better to break it on the test stand rather during a run.

[stoffe64]

Sorry for your loss buddy.....i hope that the wheels survived that torture..atleast you had oil pressure now.
Better luck next time!
Cheers/Stephan

[Johansson]

I disassembled the engine after the smoke had cleared and found that the compressor nut had come lose.

I had angle torqued it to 130° and used Loctite, so it should have been ok. The manual says 130-145° so I might have to tighten it down a bit more from now on.



Some of the damage seen is from the oil filter spanner I had to use to remove it from the turbine shaft, the compressor wheel had fused itself pretty good to the shaft so I had to use both the hydraulic press and a propane torch to remove it.



Since the shaft looked a bit worse for wear where the comp sits I will fit the spare turbine shaft and keep this one as an emergency spare.

I haven´t disassembled the shaft housing and checked the bearings but they feel tight and the rotor turned freely so I think they are ok. I´ll get me a spare bearing kit and a new KTS X846 compressor and then I should be good to go again. Awesome news that 24V to the oil pump has cured the pressure issue!

Cheers!
/Anders

[Johansson]

John, with the clockwise turning rotor and the right hand thread the turbine torque is trying to loosen the nut, so if the compressor slips on the shaft the nut will come lose.

How hard are you tightening down the nut? I angle torqued it to 130° and used Loctite.

[racket]

Hi Anders

LOL..................looks like I'd better pop the spare comp in the Post for you :-)

The good part is that lotsa bits survived.

Hopefully it wasn't the thrust bearing failing and allowing the comp to move forward and contact the housing which would have instantly untightened the nut .

Hows the turbine wheel itself look ??

Lots to be learnt from the "autopsy"

Cheers
John

[Chuks]

Hi Anders,
Congrats and sorry for that huge loss.
You must have a big heart, I would cry.....

[racket]

Hi Anders

Crossed emails , I generally can't get the full amount of angular tightening as the billet comp material is "harder" than the original cast wheels , I just tighten until I can't turn any more on the T bar and socket , Locktite used as well

Cheers
John