I took the axtell by pass out of my cam plate because I didn't like the high pressure. While I was removing the bypass I noticed there was a scoring on plate where it meets the pump. The geroters are proud of the pump and it seems like they would have to rub against the plate. The mark on plate looks worse than it actually is. Can't catch it with a fingernail. What's too keep this from happening?
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Runout on the crank is causing that, Have you measured it on the pinion side, I would definitely check it while you have the camplate out of the motor. It can run a long time like that.
I suspect that it's just the anodizing wearing off. I'm not sure you can stop it from happening.
Here's a pick of my SE cam plate, this is from the rear cam thrust surface rubbing against the cam plate. About 40k miles worth. You can barely feel it by touch.
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Quote from: bteski on December 02, 2018, 05:54:26 PM
Runout on the crank is causing that, Have you measured it on the pinion side, I would definitely check it while you have the camplate out of the motor. It can run a long time like that.
Runout is .0018 measured it when I got bottom end back from Darkhorse 1800 miles ago. I did not measure it this time. Same as Brian, can't catch it with a fingernail. Obviously, some aluminum or the anodizing is being removed by the gerotors. What is supposed to cushion that? I never thought about this before, but it seems like there is no way to stop the gerotors from wearing the plate?
Been working on the twin cams since they first came out and have seen this on just about every single one, some just worse than the others. Same as it rubbing in the back of the pump. The wave washer in the pump makes it worse I think. Just my thoughts.
I agree. The wave washer is much smaller than th flat washer also. Maybe if it were designed so it could be centered on install, the pressure on the plate would be even.
Al, here's a pic of the entire rear of the plate. You can see where the pump has been wearing against the plate. Like I had said, about 40k miles.
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Thanks Brian.
QuoteI suspect that it's just the anodizing wearing off.
:up:
QuoteI'm not sure you can stop it from happening.
you wont, a perfect crank will reduce but not stop it
... seen better days ....
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Quote from: FSG on December 02, 2018, 07:02:36 PM
... seen better days ....
I fixed that issue already. :smile:
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I think it has more to do with the oil pressure acting on the georotor, than crank runout.
There must be a little "rock" in the gears on the shaft.
Notice both plates showing wear on the same side.
Quote from: speedzter on December 02, 2018, 10:03:36 PM
I think it has more to do with the oil pressure acting on the georotor, than crank runout.
There must be a little "rock" in the gears on the shaft.
Notice both plates showing wear on the same side.
That's what it must be. I noticed the same phenomenon with my Feuling camplate and pump running on a Darkhorse reworked and balanced crank with a pinion runout of 0.001. It is just the anodized surface of the camplate, it is running like that since ten years, no detrimental effects here.
Armin.
That one side wear is from oil pump pressure forcing the rotor that way. Normal. What I don't care for is the anodizing wearing off and going through the motor. It's an oxide, much like what sandpaper is made from.
Ron
That's what led to my question about the bypass, I can see a slight shimmer in the oil. I thought it may have been the filter bypassing due to the huge increase in pressure. Axtell bypass is out and I'll see if it's caught in the filter now. Not anytime soon though. Winter is here.