Well, we just got the engine from the 87 RX7 apart. We haven't cleaned
up the parts, and it looks like we might not have to - at least the
rotors and e-shaft. At first glance, it looks like the rotor housings
might be OK. The end and intermediate housings look like they will have
to be lapped & re-nitrided.

I have attached some pix of the e-shaft and rotors. Looks like we have
had a coolant and/or lubrication failure. What do you guys think? I
think the e-shaft is junk.

Can the Babbitt be replaced in the rotors or are they a total loss?

Good thing I have three more engines on the way. :)

Doc Custer
Retired Software Engineer and sometime Audiologist

That is a fine looking engine Doc. Somebody ran it low on oil from
the looks of it. I would polish the front rotor journal
with 600 grit or 800 grit emery cloth and press out the old
bearing shell in the front rotor of course. Check the oil passages
in the e-shaft and make sure they are not plugged up. From what
I can see the rotors are in fine shape. Take some more pictures
of the rotors out of the engine. From what little I can see even
the rotor housings look OK. If no apex seals are broken you have
a flyable engine there IMHO.

Finn Lassen ran his engine up to 10,000 RPM without oil or load and it seized.
He chiseled it apart and  resurrected it and flew it for years until
he mistakenly landed his airplane in the woods at night.
In case you were wondering he was not hurt.

Have you downloaded the shop manuals yet?  I say this because I
noticed you used the word "babbitt". Real poured babbitt bearings have not
been used for 75 years. They are now called bearing shells or inserts.
You press the inserts out with a tool that is just the right diameter.

Depending on how deep the wear marks are in the end housing
you may not have to have them re-nitrided. It tells how to
check them in the shop manuals. All you may need is a bit of
re lapping.

Paul Lamar ...No rotor no motor.

Good news, indeed! I/we are greatly cheered. The guy in the pix is my grandson David. He and his dad, Ken, are coming to SNF with me.

We have the shop manual.

I used "Babbitt" because that is the term Bruce Turrentine uses in the DVD on how to overhaul the 13B. I will no longer use the obsolete term. I promise. :)

BTW we will not arrive until Friday PM. I hope you will be around Saturday and Sunday. We leave Monday.
I definitely want a copy of your book.

We are in the process of finding a tank big enough for the rotors. As soon as we get the rotors and other parts cleaned up I will send more pix.

Doc Custer
Retired Software Engineer and sometime Audiologist

I'll be there on Saturday but every body splits Saturday night or early Sunday morning. Better to get there on Thursday
or Friday. By Sunday morning a lot of airplanes are gone
and the locals come for the airshow.

Paul Lamar ...No rotor no motor.

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