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-   Rotary Engine Building, Porting & Swaps (https://www.nopistons.com/rotary-engine-building-porting-swaps-55/)
-   -   Bad rebuild (https://www.nopistons.com/rotary-engine-building-porting-swaps-55/bad-rebuild-65764/)

BOTTLEFED 05-13-2007 12:03 AM

This motor was rebuilt by a supposedly reputable company and I got it second-hand on the forums with only 1500mi. I ran it for about 1500mi. and it started having hot-start problems.

So after swapping it out, I decided to open it up today to see what went wrong.

The first thing I noticed was the oil pickup strainer clogged with silicone and some metal particles...

hsmidy 05-13-2007 12:12 AM

well its more than likely that the silicon came from putting to much on the sump, looks like from the photo theres quite abit on the inside of it, as for the metal particals i would have expected them to be outta the system by now, unless the previous owner hadnt given it that many oil changes during its run in period

BOTTLEFED 05-13-2007 12:15 AM

Notice in the last pic the blue - for some reason the shiny refections turned blue on my camera.

You can see that there are shiny (blue) metal pieces on the strainer.

Also notice the amount of silicone on the oilpan mounting surface and how it squished into the pan area inside.



Here is just an example of some of the weird places I found silicone sealant. There was silicone in the oil passages but I did not notice any passages clogged. You can see that there was silicone under the OMP gear and the oil pump drive gear.

BOTTLEFED 05-13-2007 12:23 AM

I'm not sure of the oil changes but he claims the breakin was preformed by the book.



And last, the probable cause of the problems. The seal has broken through to the water jacket and the iron lip is gone. My question is, was this something that happened during the rebuild or from something else? Also, what else should I check for/replace that could have been damged by this?

BOTTLEFED 05-13-2007 12:29 AM

After thinking about this break and looking at the pic, it couldn't be from detonation because at that point it is on the exhaust stroke.

heretic 05-13-2007 01:09 PM


Originally Posted by BOTTLEFED' post='871629' date='May 12 2007, 09:23 PM

I'm not sure of the oil changes but he claims the breakin was preformed by the book.



And last, the probable cause of the problems. The seal has broken through to the water jacket and the iron lip is gone. My question is, was this something that happened during the rebuild or from something else? Also, what else should I check for/replace that could have been damged by this?



Overtorquing the tension bolts can cause that, especially if it was already weakened from casting core shift or corrosion. It is not uncommon for those pieces to break out, or to pull apart an engine and find one broken out even though it was still running fine before disassembly.



I suppose that an excess of sealant on the O-ring could crack that piece out as well.



In short, it's really hard to say whose fault it was, since those can break at any time, even if they seem to look okay before assembly.

kahren 05-13-2007 05:02 PM

if a little silicone is good, more is better!

BOTTLEFED 05-13-2007 05:16 PM

OK, so if this did not cause running issues then what could have caused hot-start problems?

The engine builder said I probably have warped apex seals from running lean - which I doubt since I was running an overly conservative tune (9-10 afrs). How can I measure for warped apex seals?

vosko 05-13-2007 05:26 PM

did someone use a chisel on that water seal holy crap

hsmidy 05-13-2007 07:36 PM

well u can say for sure the excess silicon is from the rebuild, shouldnt be that much in you oil no this long after its been broken in,



get a flat surface(must be true or true enoff) and use a straight edge and some feeler gauges to check if ya apex seals are warped


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