Quote:
Originally Posted by orange4boy
. . . second for the regen growl . . .
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Uh Oh. Please do not 'set your hair on fire' but regen should be fairly quiet. I typically hear inverter 'whine' a mosquito like noise and not a rumble:
- Does it remain if you shift into "N" while rolling? The reason is one of the symptoms of a failing transaxle is a short in the MG2 stator. This causes what has been called a rumbling sound that is proportional to the speed. The stator winding short also leads to excessive MG2 temperature, which the mini scanner can detect. I'll record the hill roll-down test starting at 0 km/hr and let it roll as fast as it can ... turned out to be ~38 km/hr.
I'll record regen down a hill on the way home this evening and post a URL where you can hear it. I'll call out the speed in km/hr since the fixed gear ratio will set the frequency. It only reached 38 km/hr on the hill roll down.
Tires and alignment can also cause a rumble as well as a bad wheel bearing. Let's keep the ambiguity group open. It is not uncommon to find one problem masked by another. Fixing the transaxle just means we can look at the next.
If on a highway run of moderately high speeds and 30 minutes duration the MG2 temps are lower than MG1, then I would give the transaxle a clean bill of health. Let me know what sort of convient highway speeds you have available and I'll replicate the test in Huntsville. We've had a cold front come through with night time temperatures around 0 C.
Hummm, you might want to double-check the transaxle oil level ... you never know. Oil helps dampen gear noise.
PLEASE don't take this as anything but curiosity. It may be your ear and mine hear different things. The iPod recording should help answer the question. The reason is the rotor speed is geared down compared to the wheel bearings. The frequency vs. speed should be a good tell.
About the old transaxle, folks are always interested in what the guts look like. I suspect we'll find the Power Split Device (PSD) is fubar; the 'silent chain' still there; and everything else ... most enlightening. Your friend interested in making an NHW11 into an EV might also want a bench 'test article.'
The position encoder of the NHW11 is a little tricky but obviously it works. Once he gets a chance to 'look at the guts' on the bench and run a few tests, he may come up with a better plan. <grins>
Bob Wilson