jmcquivey

Freshly 'rebuilt', we finally got my 12A back in my car, and it runs really well other than one thing-- a mysterious knocking coming from the rear rotor. We have eliminated all ignition problems by pulling the spark plugs. The knocking, although distinctly quieter, is still there -- it is apparently mechanical.

Is it possible to put the rotors on incorrectly, or anybody have any ideas as to what it is?

The only idea we've had is that maybe I didn't clean my apex seals/springs well enough when we had them out and they're sticking open. Any ideas would be appreciated.

Thanks in advance.

cpa7man

iTrader: (2)

Last time I had a noise like a slapping/knocking sound I'd spun a bearing.

Rogue_Wulff

That would be my thought, as well.

Kentetsu

Make sure your plug wires are routed correctly. If there was an ignition issue, causing spark at the wrong time, it could sound like a knock...

jmcquivey

Is that a bearing inside of the rotor?

DriveFast7

iTrader: (1)

Only time I heard the slappy was a spun rear ROTOR bearing.

coxxoc

iTrader: (3)

Rotor bearing or stationary gear. Time to take it back apart.

slowautoxr

iTrader: (6)

I had a similar noise in a motor. I haven't disassembled it yet but when I drained the oil, I found "gold nuggets" in my oil I suspect the rear rotor bearing as well.

Viking War Hammer

iTrader: (8)

bearing

Roundabout

iTrader: (8)

^ Nice jugs lol!

cpa7man

iTrader: (2)

Correct......don't feel too bad, I blew up two engines this past weekend.

jmcquivey

I can't seem to find the rotor bearings online anywhere. I found one site that has a set for the 13B on sale. Do I just have to buy a new rotor to get one?

MIKE-P-28

iTrader: (1)

mazdatrix.com

djessence

They need to be pressed in and out. Mazdatrix, Mazda, Atkins all have them. Im sure many others do as well.

Just making sure you realize that *IF* in fact it is a spun bearing that means a rebuild. Like complete dissassembly of the core.


Just making sure that is clear. Finding one is the least of your worries (think they are about 25 bucks but you need a gasket kit 100, and potentially many other parts depending on condition/mileage of your engine)

Rogue_Wulff

Normally, a spun rotor bearing will also damage the rotor, the e-shaft, or both.......
Hate to break it to you, but it's best you know before hand.

teddyrx2

iTrader: (33)

Check the fuel delievery...might be starving for gas...check the route of the spark plug wires one may not be all the way on...or they maybe on wrong...

And last mut not least it maybe a spun bearing...sucks yeah but welcome to the world of rotary...anything goes and it always does...

jmcquivey

Thanks for all of your help, guys. But like I said before, it is strictly mechanical. We pulled all four spark plugs clear out. The compression is a tiny bit weak on the rear, but the knocking is still present when the ignition is taken clear out of the picture.

It is also a brand-new rebuild with 0 miles on it. We put it back in after rebuilding it, and discovered the knocking. At this point, I don't think the e-shaft or rotor have sustained any damage because as soon as we heard that it was knocking, we turned it off.