teknics

This is basically going to be my writing area of personal technical ideas, theories, or whatnot. I figured I'd invite you guys into the discussion so as to see some other points of view or your own personal theories.

***Please no bullshitting, no trash talking. This post is intended for open expression of theory, opinion, fact, anything describing the technical aspects of the renesis/13b-msp.***
***There is no specific topic other then that, so please stay on it***

I'll start by talking rotors. Lately I've been thinking about the change in rotors between the 13brew and the 13bmsp. Mainly revolving around the new method of balancing.

But first lets begin with the e-shaft, before you can discuss rotor balancing you need to know the e-shaft is also balanced. This has remained the same style, all engines have a balance weight on the front, the rear is balanced by the flywheel (m/t) or a counterweight (a/t). Since they are all essentially solid items and they are dynamically balanced so in ALL situations the balance will remain the same (considering a factor of 0 e-shaft flex/bounce, generally only found in 3 rotors or high-powered high-boost rotaries anyway)

The old rotors were statically balanced hollow objects, balanced like any other solid object (flywheel, counterweight, etc) by drilling out the surface to balance the weights. This enable a true blueprinting of the motor and allowed you to know and be able to demonstrate on a balancer how the rotor will spin at all times. Mazda changes this to now factor in the conditions within the rotor. By using the interior of the rotor as a factor they leave it open to variables. The weight of the rotor itself and the position of that weight doesn't change, the interior situation however is constantly changing with no way of factoring in "environmental" changes on the interior rotor surface. (edited as per stealhtl's description/explanation below)

Attached is an image describing some new features of the rotors and a decent cutaway diagram to better understand what I've been thinking. So read that over, or open it in another window and reference it as I'm explaining this.

Now the interior of the rotor is hollow and an oil jet plug injects oil into the hollow core. That is how the rotor's are now balanced. Does anyone see the potential problems arising from this? Basically the first sign is that it impossible to show this fully functional outside the motor, that i could think of, that would accurately recreate what would happen during driving and long term. Change in oil weights by customer, poor oil quality, poor maintenance, weak pump, loss of oil pressure caused by low oil level and oil slosh at the right time....etc Nevermind the temperatures, pressures and other forces being exerted on the rotor during engine running.

Also consider the carbon problem the motors are having, a lot has to do with dirty oil getting basically baked. Now here's a rotor being balanced by that same oil... considering those two factors I'd imagine it's safe to assume large particles and possibly carbonization or at least "gumming" of the oil within the rotor, if not completely clog the e-shaft oil jet. That would create all sorts of problems on multiple scales. There you have a perfectly balanced high-rpm spinning eshaft and then you have rotors whose position and balance is important and factor as always being within a certain spec, suddenly, possibly, drastically out of spec. Combine this with the obviously limited lubrication in the housings and other natural problems the Renesis is experiencing and a think you have a possible problem that I have not heard mentioned in public yet.

Also remember they changed the design of the rotor gearing, one rotor's gear (the gear itself not the rotor) goes one direction the other goes the other way. In the old rotaries they both went the same direction, coincidence most likely but could it cause problems that we cant imagine happening? Resonant frequencies have a large effect on some strange problems. Hell a brake squeak is caused by two things rubbing together and with bad conditions the rubbing hits a specific resonant frequency and a squeal is produced. Could this be possible from a gear swap? Remember almost all key sealing areas of a rotary are two metal surfaces rubbing together at all times (side seals in their groove and on the plate, corner seals in the rotor and on the plate, both halves of the apex seals and the halves themselves rubbing together) Anyone have any random thoughts as to what possible differences could be caused by changing the gear direction of one rotor? im just throwing stuff out there lol.

I also have some new thoughts on why the series 1 omp was even more ineffective then i originally considered because i overlooked a simple factor, but we'll get there when we get there.

So let's see where this goes....next?

kevin.

PSTNLSS

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I am subscribing and taking a front seat in this class.

StealthTL

iTrader: (1)

I think your assumptions may be erroneous.

The old rotors were solid objects

The rotors where never solid.

Now the interior of the rotor is hollow and an oil jet plug injects oil into the hollow core. That is how the rotor's are now balanced.

The oil does not 'balance' the rotor. The oil jet doesn't operate 100% of the time.

Change in oil weights

Oil 'weight' is misleading - it refers to viscosity, not physical mass.

teknics

Solid was a poor choice of words, sign of my thought process going and lazy typing ensuing. "machined-faceted hollow cast iron chamber, balanced via the addition and subtraction of cast iron material along the outer perimeter of the flat faces of the rotor" doesn't roll of the tongue, i was in the process of looking for a pic to use as an example (i constantly go back over my posts to realign my thought process )

As for the "oil does not balance":

As per mazda the mass of oil *entering* the rotors is used for the dynamic balance measurements. The problem with the factor is they can't measure and factor in the oil which *remains* in the rotor, caused by the "dirty oil" part of my post. One sticky mass of oil equals a big weight difference when viewed to scale.

You assumed i meant weight as in measurement of mass? Oil viscosity does not measure weight it does provide a scale of "movability" within a pressurized system, pressures can rise and fall based on viscosity.

good definition here:
So Oil *viscosities/weights* will effect an equation based upon the movement of oil within the hollow interior of a rotor, why? Because even viscosity alone is an ever-changing factor. Viscosity changes as motor oil is broken down during use, no way you can nail down the specific rate of the motor oil's "breakdown", especially if you cant even guarantee the viscosity that you will begin with.

either way, I'm just saying, maybe it's possible this is somehow a small possibility? It is an incalculable factor, how important is the equation it's in? Personally I don't know but the only way to find answers sometimes is to open doors...

also I repaired the paragraph you reference to make it more clear as to my description of the matter.

kevin.

nycgps

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Save it for later.