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-   -   help determine if housing is useable. just not sure. (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/help-determine-if-housing-useable-just-not-sure-385642/)

aka_rocket 01-14-05 02:27 AM

newbie rebuilder. help check if housing is useable. just not sure.
 
4 Attachment(s)
being my first time opening up a rotary, i wasn't too sure if one of the housing was ok or not. this is a low mileage s5 motor which im intending to use the housings and rotor if its good. if the housings are not so good, i will prob. reuse my 86s housings (but they are pretty high mileage). here's the pics, still useable? there seems to be some grooves(probably the wrong word to describe it but only one i can think of) on the inner part of the housing. circled it. karack and i opened it up and thought that it might cause some chattering later on. doesn't catch the fingernail but noticeable to the touch.

RX7goZoomZoomBoom 01-14-05 03:01 AM

Dude they are reusable if you want to build a shitty engine.
They will seal but don't expect much and it will definatley be slower than stock.
Those housing by there were patterns and colour tell me that that engine was under some extreme heat conditions. More that likley they are not true check there flatness on a glass table and I bet they will wobble.

My opinion only
I would get new housings or better used ones.

aka_rocket 01-14-05 03:11 AM

thanks alot. that was kind of like our (karack's and my) conclusion. i guess i will just use the s5 rotors (they are fine) and reuse everything else from my 86. as far as i know, my 86 is only suffering from oil o-ring problem. well see when i open it up tomorrow.

Nef003 01-14-05 03:11 AM

yeh..they do look pretty worned out..
you can really tell they were beat on pretty hard..
that rotor was peeling the metal. lol

RETed 01-14-05 04:08 AM

How deep are those "ripples"?
If they are not THAT deep, fuck it, reuse them.
I notice that S5 rotor housings all come out like that cause of the E-OMP.
For some reason, I don't think the E-OMP injects as much oil as a Zenki mechanical OMP, so there's this weird center wear on all those rotor housings.
Maybe some other S5 NA rebuilders can chime in here?
Rotary Resurrection around?


-Ted

patman 01-14-05 07:29 AM

junk...it will take like 10k miles to get even marginal compression out of those.

pat

aka_rocket 01-14-05 03:19 PM

i just hope my 86's housings are ok or else my rebuild will take longer then expected.

RotaryEvolution 01-15-05 01:24 AM

i was more concerned with the horizontal chattering than the vertical lines, the vertical OMP grooves are slight and you can barely catch your finger nail in them but if you rub your nail accross the bottom edge from the spark plug hole to the exhaust port there is a chatter pattern about 1/2 of the way lenghtwise to the exhaust port. the chattering would cause the apex seals to wear prematurely and lose exhaust compression resulting in a loss of power, only one rotor housing is bad enough for me to question it, i haven't seen a rotor housing in this shape so we thought it would be good to see if anyone else has seen a 'chattered' rotor housing and if it worked ok in a rebuild.


here is the best picture showing the horizontal lines, you can see the light glinting off of a few of them.

https://www.rx7club.com/attachment.p...chmentid=90743

RotaryResurrection 01-15-05 01:46 AM

You all are full of shit (the naysayers that is). No offense, but you don't know what you're talking about. Those housings have pretty normal wear, nothing unusual or bad, and are worthy of 110-115psi of compression all day long. I'd use them in any engine, including one built for my own car (in fact my FD has a set similar to that, from an s5 NA modded to work in the REW, making 120psi compression might I add).

Yes, all s5 housings look like that to an extent, with any more than 75k miles on them. Some of the older ones do too, but more s5 than anything. The main wear to be concerned with is on the very rear edge of each housing...the chrome flaking. The more flaking the less compression you'll have.

IF you have money to burn or just think you'll lay awake at night worrying about this, then don't use them. Otherwise they seem to be fine to me.

Fritz_X 01-15-05 01:51 AM


Originally Posted by RotaryResurrection
You all are full of shit

:bigthumb: Taken out of context but priceless....

--Fritz

RotaryEvolution 01-15-05 01:54 AM

yeah thanks for the compliment...

my rotor housings were in perfect shape compared to these but they were from an S4 T2, i would have thought they should have been trashed but the n/a would be mint because of the lower stress levels. i only asked for a simple yes or no answer not a sarcastic reply..


think of it like going over a series of about 200 speed bumps going 100MPH, i would think that either there is wear there and/or the seals wouldn't be able to seal properly with the ridges in the housing but if you say they are ok then i will let him know and we can use them instead of his S4 housings.

RotaryResurrection 01-15-05 01:57 AM

I was referring to the "naysayers" as being full of shit, not you karack.

BTW, to the original poster, the housings in the 86 will look quite a bit worse than these...more chrome flaking by far, and an overall dull finish as compared to the s5 housings are normal for the older ones...the coating is not as strong or stable on the s4 housings.

RotaryEvolution 01-15-05 02:00 AM

oh ok, and we will have the S4 engine out tomorrow if the S5 rotor housings are ok for the rebuild then we won't have to tear down the S4 motor. :) there is 0 chrome flaking on the S5 housings.

patman 01-15-05 08:53 AM

general rule of thumb is, if it doesnt catch the nail, its usable. looks pretty bad in those first pics, tho. might just be the pic.

RETed 01-15-05 06:07 PM

See, no one believes me... :D


-Ted

aka_rocket 01-16-05 02:20 AM

ok, sounds good. thanks everyone for you help.


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