White_FC

Hey all,

I'm going to do a 'budget' rebuild, (read: doesn't have to last long at all...) just until I get a new engine.
I'm wanting to reuse nearly everything from my old engine, like the rotors/housings and side plates.

Only thing is that one of the rotors for a little bit damaged when one of the apex seals let go..
It's a nick about 1mm deep leading up to the apex seal groove for about 2mm long.
The actual apex seal groove is still dead straight as it should be, just there now a little groove heading up to it.

The housings, one of them has some small(?) 1mm deep grooves going for about 3cm starting after the oil injection bung hole (heh heh heh) and going towards the trailing plug hole..

Would these cause a _significant_ drop in compression? I know this is faaar from ideal for a rebuild but i'm wanting to try out some different porting and what not, and just basically have my first go at rebuilding a rotor.
I'm going to buy some apex seals from rotary aviation and use those, all the other hard seals are within spec.

Before I tore it down it still had enough compression to give 5 even pulses and then only one far less even pulse
So that tells me that the housings should give enough compression to run ok?

trickfc

if your spending the money on seals and everything, just call up some engine builders and find a cheap housing. take the rotor to them and have a look at it. its hard to say w/out pictures and whatnot

RotaryResurrection

iTrader: (8)

PICS and I'll tell you.

Bambam7

The rotor may be fine, it's ok if it's a little chewed up, as long as it's not deformed, punctured, or has peices sticking out of it. The only realy bad thing that can happen is that over the long term, carbon can build up in rough spots and depressions, and can eventually flake off, causing problems.
As for the housing, that sounds questionable, but possibly usable (but only to have a running engine).

If possible, stick the rotor in the housing with the shaft and stuff in place (might take 1 min to set up) Rotate the rotor untill it's at full compression on the plug side, and see how far into the groove (if at all) the upper apex seal has travelled.
If it hasn't even hit the groove, then compression won't be affected, and you're golden- but power will suffer a tiny bit due to blowby, but not by much at all. The only thing you have to worry about here is gradual deformation of the seal and housing after the groove, where it's constantly experiencing the blowby.
Regerdless, I wouldn't use it at all. You are going to go through all the trouble of pulling the engine again and all that in a little while?? Forget that, just replace that housing, and whetevr seals you may need, and you're fine.

White_FC

I will endevour to get some Pics for you all ASAP...

Like I said I just want to get this engine running again, i'll worry about making a good, powerful and reliable engine when this one dies, I want to use brand new housings, better rotors aswell next time I do a rebuild, which is why I basically want to use this as a practice run.

I'll dummy up half the engine tomorrow and tell you where the apex seal goes over the scratches so see if it'll srew my compression totoally.