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-   3rd Generation Specific (1993-2002) (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/)
-   -   used JSpec motor blew 1 mile after installed. -- vent thread (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/used-jspec-motor-blew-1-mile-after-installed-vent-thread-957016/)

zeeshan 06-06-11 12:44 AM

i should have the engine out tomorrow to see the cause

MrNizzles 06-06-11 02:13 PM

installed a used jdm engine, without breaking it down to inspect and putting in fresh seals... that is about as newb and cheap as it gets... I think I learned that my first week here on the forums... isnt there a sticky about this?

Im betting it was an a apex seal (or two) that cracked and blew off... and/or something wrong with an iron or housing, causing apex seal to "catch"/"stick" and then break.

Whens the part out thread coming? dibs on black interior!!! also looking for cca/ccv actuator on y-pipe. Hows the harness?

jkstill 06-06-11 10:56 PM

Hmmm...

Been boosting my single turbo FD pretty hard with 3 years of autoxing on the 5 year old motor without issue.

Well, maybe some issues, but never the motor.

zeeshan 06-08-11 10:27 AM

well the engine looks like it was mint. not sure what caused the seal to pop off one of the groovesi n the front rotor. the front rotor is useable if you go to 3mm seals.

zeeshan 06-08-11 10:30 AM

rear rotor
http://i130.photobucket.com/albums/p...age/rrotor.jpg

front rotor housing seal metal that was left on the housing (seems to come off if i scrap it with my nails)
http://i130.photobucket.com/albums/p.../fhousing2.jpg

a little small groove caused by the apex seal
http://i130.photobucket.com/albums/p.../fhousing1.jpg

front rotor
http://i130.photobucket.com/albums/p...age/fseal2.jpg
http://i130.photobucket.com/albums/p...age/fseal1.jpg

MrNizzles 06-08-11 02:48 PM

mint? really?

from what I have read here on the forums from the builders who have all the experience (unlike me) is that the problem with these motors is they sit for a long time, for years, with some coolant still in them...

that coolant is corrosive and eats away the metal, especially in thinner areas like the coolant seal jacket walls.

It doesn't take much for something to be out of spec or out of alignment and then how are the apex seals supposed to stay in place.

That last pic, the rotor looks toast.

The omp adapter looks to be in pretty good shape, but again, with these motors, everything is told in the measurements and spec. If it's in spec, then its potentially re-usable.

All in all, it does look like a better than avg jdm motor. I have seen pics of jdm motors torn down (again from experienced members here), that were so bad in many ways.

but ultimately, what was probably the downfall, is sitting for so long and allowing coolant and dirt to eat away at the metal.

RotaryEvolution 06-08-11 03:41 PM

i believe he meant wear wise, it's obvious the rotor is now junk due to the debris that is embedded into the face.

the coolant issue is opinionated, meaning all jspecs aren't even good cores because they have corrosive coolant sitting in them which would require all the irons at least to be replaced, of which i doubt the person who said that does on jspec rebuilds or pushes it. ignoring his own opinion on the matter.

the issue i recommend tearing down the jspecs for is due to high carbon buildup and coolant seals that have hardened with age and usually have no flexibility left in them and have a tendency to fail within a short period of time after first startup.


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