It looks to me like the dowel pin is a very close tolerance fit to the groove that keeps the rotor gear in phase so the rotor follows the correct eccentricity.



The bolts take the side load but since they are a loose fit to the gear they alone cannot keep the rotor in phase. Just as we have 2 dowel pins to locate the rotor housing instead of relying on the tension bolts.



Why was the pin wiggled out of the bore with no damage or loosening to the bolts? I believe it is because the stationary gear was rocking back and forth (as the wear on the groove indicates). This shows that the bolts cannot hold the stationary gear stationary.



But obviously I have been wrong before, so I wouldn't be too surprised if I was wrong about this as well.



Perhaps next build I will put a bug screen back on the pick up. My car could use some idiot proofing with me around https://www.nopistons.com/forums/pub...IR#>/smile.gif

Blue TII, You are right it is those things too. I was mostly addressing the pump failure. But interested, did your rotors touch the housings? They have a certian amount of float on the gears.

I use 680 loctite for high temp items like that.



One trick; use loctite 515 gasket eliminator as a thin coating on the oil passage area, on both stationary gears to end plate interface( you can wipe out any excess with a Q-tip thru the bearing oil port.

Barry

maybe take the old pin, and buy some screen it wont fit thru https://www.nopistons.com/forums/pub...#>/biggrin.gif



stock screen is really fine, i bet a coarser screen would flow much better, but still keep the bits out

I only took the oil pan and front cover off to put in a new dowel pin and oil pump. I haven't seen the rotors or housings yet, but it is running well again.



Mike, with my luck it would be something just a LITTLE smaller the next time- lol.



What killed the last engine was EGT probe melted off and some of the thin SS capilary tube wedged inbetween the rotor and rotor housing at the corner and stuck a corner seal in its groove.

maybe you need the koseki header. it turns the rotary engine into a zero emissions unit. you just need a header tube that connects one exhaust port to the other....

But then when you spit an apex seal outta one rotor it will be sure to get shot into the other and then it REALLY won't run 'cause you got both front and rear blown out.