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Turbine Builder
20th May 2019, 08:39 PM
OK more Rotary Engine projects. I got a couple of these OMC Rotary Engines, these engine were use in the Evinrude & Johnson Snowmobiles back in 1974, these two are the 45 hp versions there is a 35 hp version as well. This project has not started out well I took apart the first engine as you can see the housing is severely damaged I'm not a happy man at the moment https://vintagesleds.com/bs/Smileys/default/sad.gifhttps://vintagesleds.com/bs/Smileys/default/sad.gifhttps://vintagesleds.com/bs/Smileys/default/sad.gif

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Turbine Builder
20th May 2019, 08:48 PM
The auxiliary air valve is a fatal flaw on these engines, if not remove this is what happens. I finish off the tear down of the engine and clean up the main parts of the engine, the side plates are in good cond so is the E shaft and the rotor. One thing i notice on the rotor there is a blind rivet, is that rivet meant to stop the bearing from slipping out ? I think i will replace the rotor bearing as well and replace the apex seals. and housing.

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Turbine Builder
20th May 2019, 08:53 PM
I clean up the housing so i can get a better look at the damage

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Michael G
20th May 2019, 10:05 PM
Ouch - that's not nice. Can it be welded up or will that warp everything to buggery?

Michael

Turbine Builder
20th May 2019, 11:52 PM
Ouch - that's not nice. Can it be welded up or will that warp everything to buggery?

Michael
No not nice,but that's why it was cheap. No can't weld it to much work and need to strip off the special coating and re coat it and machine it to the right profile and could warp everything. I place a order for a new housing from Freedom Motors (http://www.freedom-motors.com)

Turbine Builder
21st May 2019, 06:15 AM
I clean up the rotor and cooling fan components. The fan housings have a few cracks in them, the rotor is in good shape. The charge coils are crack, new ones are on the way.

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Turbine Builder
21st May 2019, 09:34 PM
Got a couple of new parts. New housing and new corner seals and springs and new Stator.

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Turbine Builder
21st May 2019, 09:46 PM
Been going through the Electrical system, the new Stator i can not use only the charge coils. The power pack, starter solenoid looks to be ok but the ignition coil is toast :( So on the look out for a new one. I have notice a lot of coils to suit OMC Johnson Evinrude Outboard Marine motors

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Turbine Builder
22nd Jun 2019, 02:40 PM
I drilled and tap a 1/8 pipe thread to seal off the valve

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Turbine Builder
22nd Jun 2019, 02:45 PM
I decided to pull apart the second OMC engine. This engine has been sitting for a very long time, all the seals are stuck so will give a good soak for a while. As you can see in the photos of the rotor there is a blind rivet and also a pin in the bearing race cup, so looks like these engines have the blind rivet and pin to hold the bearing in situ.

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Turbine Builder
22nd Jun 2019, 02:50 PM
The housing and side plates are in good cond, there is a small chip inside the housing surface . The chip is near the intake side so may be ok for running as is me thinks.

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caskwarrior
22nd Jun 2019, 03:25 PM
What is the chip caused by do you think, detonation?

Great seeing the detail on these small rotaries keep it up.

Turbine Builder
22nd Jun 2019, 04:46 PM
What is the chip caused by do you think, detonation?

Great seeing the detail on these small rotaries keep it up.
Thanks mate. Yes that's a good question, i had another look at the housing that port on the left of the chip is the exhaust outlet. Need to do some research on this.

Turbine Builder
5th Aug 2019, 03:25 PM
I finally got most of the new parts from the US to start the rebuild. I can now start rebuilding the first engine, also been experimenting on machining up a adapter flange for the E crank shaft seal. i can get seals here in AUS for $5 The original seals are $55 USD. I'll see if i can find a smaller OD on the seal, like to have a bit more material on the bore.

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Turbine Builder
7th Aug 2019, 04:41 PM
Been busy cleaning all the parts before i start the rebuild. I decided to lap the end plates on my surface plate with 800 grit wet and dry sandpaper.

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Turbine Builder
8th Aug 2019, 04:29 PM
Got the engine back together today, got strong compression all good https://vintagesleds.com/bs/Smileys/default/smiley.gif https://vintagesleds.com/bs/Smileys/default/smiley.gif More work on the engine tomorrow. Took me a good six hours for this part of the build.

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Turbine Builder
17th Aug 2019, 04:01 PM
I screwed down the stator and stuck some high temp heat shield material on the steel cover and the charge coils, this should extend the life of the coils. i have started working on the Electricals, this is not my expertise, i need to read the manual again on how this system works and get it to sink in my head. I did find a electrical diagram looks similar to the wiring harness i got with one of the engines i have, will try with this out.


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Turbine Builder
31st Aug 2019, 08:06 PM
I got quite a lot of work done on the engine, made a test stand and bolted the engine down on rubber mounts and i think i got the wring work out, still need to work on the exhaust system and a bit more work on the electrical system.

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Turbine Builder
16th Sep 2019, 02:42 PM
I was ready to do a test start on the engine today and now have a leaking fuel pump, the pump is brand new there is no O ring or gasket that seals the top. I may have to make up a seal and see if that works. I work out the electrical system i now have Spark when cranking the engine by the recoil starter. Also finished the exhaust system.

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