Oil tank below engine

Re: Oil tank below engine

by Eugene Klimenko » 7 years ago

Eugene Klimenko

12 74 1

Yes, my situation is very similar and I should be able to copy this installation. This was my original intentions. But my designer didn't think that to have hot exhaust so close to the propeller, is a good idea. But if everybody else doing it, why not. Maybe I should call POWERFIN and ask them what they think.

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Re: Oil tank below engine

by Eugene Klimenko » 7 years ago

Eugene Klimenko

12 74 1

Made some phone calls to LEAF and POWERFIN:
- Sounds like 2" from exhaust to propeller blades not presenting any problems at all.
- Oil cooler must be installed right behind water cooler, but not in front of it.
- Oil tank must stay inside of 400 mm limits.
- New 1" balancing tube not creating any problems at all, its only helping with low RPM vibration if carbs not 100% balanced.
- Big air intake plenum can be removed and 2 separate air filters can be installed. This will create room for oil tank to move closer to engine to make room for oil cooler.

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Re: Oil tank below engine

by Roger Lee » 7 years ago

Roger Lee

131 5.38k 5.44k

"New 1" balancing tube not creating any problems at all, its only helping with low RPM vibration if carbs not 100% balanced."

The vibration comes from many sources. The carb sync is only one. The big vibration issue at low rpm is the compression. The 912UL is 9:1 and the 912ULS is 10.8:1 (call it 11:1).
Running the higher compression at low rpm beats things up and the larger comp tube will not change the compression ratio. Surely you have run some vehicle at too low an rpm and feel it shutter and vibrate. This will kill your components quick. Trying to use a larger comp tube in place of keeping the carbs synced is a band-aid at best and a poor one. There is no fix for a high compression vibration because you run it at too low an rpm.

https://www.rotax-owner.com/en/rotax-blog/item/44-912-idle-rpm

You would be better off leaving the comp tube alone and focus on your oil tank and muffler mount. Then you'll have a good setup. Installing the larger comp tube may be just throwing good money away on the tube and new intake manifolds. It won't save you any maint and won't save the engine beyond the stock comp tube.

---

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Re: Oil tank below engine

by Rob Seaton » 7 years ago

Rob Seaton

3 1.32k 251

I would most strongly recommend you leave the plenum (airbox) installed!!

Re: Oil tank below engine

by Eugene Klimenko » 7 years ago

Eugene Klimenko

12 74 1

Original muffler installation used rubber Lord mounts, but was holding oil cooler as well. In new location I need to fabricate different brackets. Do I need to use lord mounts to hold muffler? From what I can see out there everybody is using hard mounting, no rubber at all.

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