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Old 08-28-2014, 03:43 PM   #1030 (permalink)
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Astro - Yes, that's exactly the problem.

Also, regarding the intermediate shaft, I went to my shop and re-assemble the geartrain to get a better look at things. Assumming that the bottom of the oilpan is designed to be level, then the oil drain/fill holes on the gearbox (vs the motor stator) side of the case pretty much define the oil level. If it's like most transmissions, then the oil should be filled up to the bottom of the "fill" hole. When static, The motor's shaft is just out of the oil and the intermediate shaft is submerged. I don't have any idea how much this oil level drops when the vehicle is moving.

There's very little space to put things (like I've suggested) like an internal chain drive or oil pump. It would take some real creativity to somehow fit a motorcycle gearotor pump (about the smallest pump I can think of) directly below the intermediate shaft.

So this leaves three possibilities:
An external pump pulling off the drain, which is right below the geabox-side output shaft. This could be driven in a variety of ways, but the concern I would have is how to protect it from all the dirt and grime that's always in that area.

The second possibility is to use an electric pump, and move the pump to a more protected place. Also, an electric pump could be direction independant, which would be nice if the motor ever needed relocation.

The third possibility is a bit of a longshot. It would require REAL knowledge of how gearpumps work, and the tolerances involved. If the design can be worked out, actually making the parts could be relatively easy. Basically the design calls the motor output gear and the intermediate shaft input gear the "gear pump." A flat plate would be fit between the motor output shaft, the intermediate shaft, and the case. This flat plate would form the gearpump's "input" side, and the would be a strategically placed hole to allow oil to flow into the space where the two gears seperate from each other. The gearbox forms the surfaces that (with the gears) moves the oil. The place just above the intermediate shaft is the high pressure point where the gears mesh. A hole could be cut into the space directly above it, which currently forms the oil reservoir. I'm trying to figure out how to attach that plate to something, yet allow disassembly. That plate might have to stand up to fairly high oil pressures.

I need to learn how to post pics around here. I could post some scribbles that would help illustrate these babbles...

Originally Posted by Astro View Post
I was looking at the pictures of the cutaway housing and the complete housings. I can see how the large gear on the final drive shaft picks up the oil and hurls it up and over towards the intermediate drive shaft. I can also see the scoop/funnel that catches that oil and feeds it into the inside of the motor shaft.
So the problem is that if the housing needs to be mounted backwards due to space resrictions then its normal gear directions are reversed. Essentially the whole thing is driven in reverse. Which means the large gear on the final drive shaft rotates the opposite direction going down into the oil and flicking it forward off the lower edge of the gear. So no oil gets into the funnel bit of the housing and therefore no oil to cool the motor.
Hopefully that is a accurate description of the issue, if not then please ignore the following suggestion.

I was looking at the intermediate shaft and it sits so low compared to the other two shafts that it's gears should be making good contact with the oil. With the motor going in reverse the large gear on the intermediate shaft will now rotate in a direction where it will pick up oil and hurl it up over the top of the gear and forward towards the motor shaft.

Question: Would it be possible to dremmel out a section of the funnel part of the housing so that the oil splashed/thrown from the large gear on the intermediate shaft ended up in the funnel?

Edit: Actually i may have answered my own question. I saw some more photos on eBay from different angles and it doesn't look possible to go from the intermediate gear to the oil collection funnel. Oh well, maybe somebody else can figure a way of getting the oil to move without having to resort to an external pump.
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