After tearing down the engine due to a coolant leak, we discovered this small spot on the rear of the e-shaft which obviously suffered friction and excessive heat. It's been slightly ground down already but the discoloration due to friction is still present. The shop isn't worried about it but I'd like to know WHAT would cause this as there's nothing there to rub against it. All bearings were fine except for the rotor bearing on that journal which had a very thin scrape around the outside edge due to the e-shaft. All other bearings looked brand new as did that bearing on it's main face. What do you guys think?

 

Here's a closer shot...possibly just dirt contamination?

 

hmm maybe it got nicked on assembly? or maybe a peice of something got in there?



mike

 

the heat discoloration ring surrounding the spot leads me to believe there was either something in there or the shaft was rubbing against something but for the life of me, I can't figure out what.

 

Looks nasty. I wouln't use it. Maybe insuficient lubrication? What oil do you use? Probably got nicked on assembly.

 

Royal Purple 20W-50. E-shaft checked out and was in spec. Oil pressure is great. Shop says it won't be a problem but I'd like to know the cause.

 

Where the needle bearing fucked up? If so they could of caused that when the needle bearing got smashed between the e-shaft and the spacer or washer.

 

You know I didn't check...I'll look tomorrow.

Thanks for the tip!

 

He said this was the rear of the e-shaft not the front. How does the planetary gear of the rear rotor look? (the inside of the rotor as that's right where the teeth are)



Possibly there was some contaminant in the teeth of the gear & it got squeezed out with the assy lube.



Unless the e-shaft end play could've been too tight.



If the rotor bearings were new then there could've been an imperfection in it from the pressing proceedure which imediately was wiped clean, but caused the damage seen...

 

I'll check that out swerve, thanks for the head's up. Yes it was the rear too meaning no needle bearing assembly. Wasn't thinking :-)



What determines e-shaft end play? Bearing size?



Rotor bearings were brand new.