7aull

iTrader: (2)

Greetings All-
re-assembling 80 12a rebuild - noticed BOTH the reactor inserts are
cracked - one actually came OUT in 2 pieces.
OK: definition-
By INSERTS I mean the 2 circular metal tubes (all of 2" in length)
that are fitted into the exhaust port holes in the reactor that
receives the gases from the rotor housings. They are a heavy metal
sleeve that I presume keeps the heat/flame from eating away the edges
of the reactor ports by ducting exhaust into the open space within
the reactor.

ONE is now in two pieces, tho it would re-assemble back into reactor and stay in
place once reactor is attached. (pic shows it removed - it looks like the other one when installed.) This is the one that concerns me
most. I would hate to install it and find that the engine pulses
would cause it to make some sort of un-gawdly rattle or racket. Don't
think (??) that being in 2 pieces would lessen it ability to duct
gases into the chamber, tho in time it would certainly fail sooner
than a complete unit. Inserts sit in a fixed depression in reactor's
mating face, so are held "fast" by attachment to block.

SECOND is still firmly in place but has 2 cracks, on opposing sides,
so it would split with a little "help".

For all I know this is a common failure and these continue to perform
until they completely disintegrate... FWIW they are both in seemingly
solid condition, cracks notwithstanding.
I am sure removing them would cause the reactor to fail much sooner.
Unfortunately (surprise!!) the inserts are NOT sold/listed as a
separate component, so I'd need to buy a new reactor (which I believe
is selling for something like $1M if even available any more

Suspect I'm screwed here: either take my chances WITH them, or try to
find another reactor - but thought I'd seek learned council.

Thanks
Stu Aull
80GS
Alaska

DivinDriver

iTrader: (15)

I've been told by a number of experienced peoplethat this is a very common problem; they tend to crack around the base, too, and the "long" tube on the 80's tends to get flared out by backfires over time. Out of three reactors I've dealt with, all had cracked inserts.

I'm unsure just how bad the problem can be allowed to get, though, before it enters the "must replace" category.

Do you know anyone who could re-weld them for you? Probably would require TIG work if possible, to keep the distortion low and the beads small.

7aull

iTrader: (2)

Thanks DD-
can't hurt to ask a welder I guess? Depends if metal remaining can take the, er, heat.
Wonder if anyone had this prob and STILL used the inserts as they were in the reactor and what the result was...
Anyone??
Stu Aull
80GS
Alaska

GavinJuice

RX7 allnight

go with gavins idea

DivinDriver

iTrader: (15)

Considering Mazdatrix asked me for $500 (and not the 'usually $50' they mention on their website) for a used SA thermal reactor, Gavin's idea is a little expensive.

Once I get a headpipe (got a friend re-welding my old one, if he can), I'll be finding out how well my cracked-but-still-in-one-piece inserts work.

djessence

might be time to upgrade to a header hey Stu? Or was this the budget rebuild you are thinking about selling or the keeper?

7aull

iTrader: (2)

naa - selling it, want to keep it emissions-safe for the new owner. Felix Miata (well known RX7 guru on SA22 List) sez the cracks are pretty common, so I'll likely go with it as-is and see what happens...
Gavin- had me stumped for a sec...

cute
Thanks for taking the time to reply, folks!
Stu Aull
80GS
Alaska