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Trying to get input on this rotor bearing and rotor. I had Chip over at Chips Motorsports press these in for me while he was lapping and nitriding my plates. One came out great. The other looks like this. Im worried about the potential for a spun bearing, or the slight damage to the rotor where it got hammered down to become a problem. I would hope if Chip passed it, then it would be all good, but looking for any additional input.
Also worried that the rotor bearing may be pushed in where it contacted the rotor at the ear...I have a second set of bearings and have no issue using them, mainly concerned about the tweaked rotor portion.
I would press in a new one. That potentially caused a raised spot, and it's not worth the risk. Many people grind those tabs off as they are not needed, but absent the tab you will still need to line it up with the slot. It not being there would not prevent a bearing from spinning.
It's certainly not awesome, but not he worst I've ever seen so I'd say its still salvageable if you're on a budget - to be clear though if it were an engine I was being asked to assemble I'd replace it - it's still locked in place though as mentioned there MAY be a high spot so it may need clearancing.
can if you like, the soft babbet on the bearings is rather forgiving and if the rotor bearing drags you'd know it immediately. the service manual is very indirect in checking clearances, most of the bore testing tools you would typically use for this procedure are going to damage the bearing more than the simple gauge of feeling the bearing for binding or excessive slop(which is always evident by copper showing on the bearing wear surfaces). run a bore gauge over a bearing and you can see it digs right in, immediately skewing your results anyways. it's HIGHLY unlikely normal people have in their toolbox, an expensive, delicate and accurate bore gauge suited for this purpose that will not do more harm than good.
if the bearing is warped due to this procedure, you're gonna have to bore test the bearing in about 8 spots, your bearing is gonna look like a checker board inside by the time you're done.
i mean, if that's your goal, be my guest. i've only heard rotor knock one time in my life due to excessive wear and never once seen a tight bearing failure. if this was a boinger, i would certainly feel differently, but in rotary engines the rotating assembly is about the least of your worries. i certainly understand a person wanting to be very focused on doing things by the book, but in this case it won't buy you and favors from the engine.
if the break in process was to be ignored, i would also agree, that there must be slop tolerances met. but it's pretty rare for people to build an engine only to immediately beat the living **** out of it.
one could lay feeler gauges in the rotor and use those as bases for the measurements, then add the thickness of the feelers to the measurement..... if one were really that adamate about doing it the right way. that would protect the bearing for a normal/cheaper bore gauge set.
some of the factory procedures are rather silly, this is actually one of them because it should require speciality tools but they basically show you how to do it incorrectly anyways.
i just quite simply do not understand the hassle, if you put the rotor on the shaft and tilt the rotor back and forth and observe even minimal deflection present, the drag should be sufficiently low enough for break in to begin.
can if you like, the soft babbet on the bearings is rather forgiving and if the rotor bearing drags you'd know it immediately. the service manual is very indirect in checking clearances, most of the bore testing tools you would typically use for this procedure are going to damage the bearing more than the simple gauge of feeling the bearing for binding or excessive slop(which is always evident by copper showing on the bearing wear surfaces). run a bore gauge over a bearing and you can see it digs right in, immediately skewing your results anyways. it's HIGHLY unlikely normal people have in their toolbox, an expensive, delicate and accurate bore gauge suited for this purpose that will not do more harm than good.
if the bearing is warped due to this procedure, you're gonna have to bore test the bearing in about 8 spots, your bearing is gonna look like a checker board inside by the time you're done.
i mean, if that's your goal, be my guest. i've only heard rotor knock one time in my life due to excessive wear and never once seen a tight bearing failure. if this was a boinger, i would certainly feel differently, but in rotary engines the rotating assembly is about the least of your worries. i certainly understand a person wanting to be very focused on doing things by the book, but in this case it won't buy you and favors from the engine.
if the break in process was to be ignored, i would also agree, that there must be slop tolerances met. but it's pretty rare for people to build an engine only to immediately beat the living **** out of it.
one could lay feeler gauges in the rotor and use those as bases for the measurements, then add the thickness of the feelers to the measurement..... if one were really that adamate about doing it the right way. that would protect the bearing for a normal/cheaper bore gauge set.
some of the factory procedures are rather silly, this is actually one of them because it should require speciality tools but they basically show you how to do it incorrectly anyways.
i just quite simply do not understand the hassle, if you put the rotor on the shaft and tilt the rotor back and forth and observe even minimal deflection present, the drag should be sufficiently low enough for break in to begin.
The service manual clearly states measure the OD of the shaft to contrast and compare with the ID of the bearing - careful use of a snap T and micrometers wont hurt or mar anything and the issue isn't babbitt its the substrate the babbitt is coating. To blatantly ignore something potentially wrong when its quite easy to check with a little bit of time is just poor workmanship.
The service manual clearly states measure the OD of the shaft to contrast and compare with the ID of the bearing - careful use of a snap T and micrometers wont hurt or mar anything and the issue isn't babbitt its the substrate the babbitt is coating. To blatantly ignore something potentially wrong when its quite easy to check with a little bit of time is just poor workmanship.
more like personal preference.
rotor bearings are almost never an issue in these engines. almost never meaning just that.
02-27-24, 02:20 PM
