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-   -   Who built this motor? Please help identify. (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/who-built-motor-please-help-identify-978551/)

jkep21 11-28-11 08:52 PM

Who built this motor? Please help identify.
 
Hi guys, I got another motor as I'm trying to source more parts for my 20b build (got a half ass 20b). I got this motor from another person and I just noticed a sticker on the eccentric shaft front bolt. The rotor housings and side housings are painted so it's surely a rebuild.

I'm going to bring it to the shop doing my build tomorrow but figured I would try to identify it before they tear it down.

It has zero compression on the rear rotor and 50 psi on the front rotor. I verified this in person before handing over the money to have him take the motor out. I'm hoping its just a couple stuck apex seals as I need the rotor housings!

Anyway her is two snapshots so let me know what you think!

http://i1123.photobucket.com/albums/...1/b9fd8097.jpg
http://i1123.photobucket.com/albums/...1/6c8cbc1e.jpg

96fd3s 11-29-11 12:57 AM

I cant help, but clearer pics might. I for one am not sure what that reads..

BlackTruenoAE86 11-29-11 01:07 AM

Does it say VOID?

MazdaSpeedDan 11-29-11 07:04 AM

I think it says VOID, an if its removed it leaves the void marks on there.

Banzai-Racing 11-29-11 07:26 AM

Atkins used to (maybe still do) put a void if removed sticker on the e-shaft bolt, however it is just about impossible to tell you who built an engine from those pictures. Atkins typically stamps the rotor housings also.

jkep21 11-29-11 07:47 AM

Thanks for the information guys. Yes, it says VOID on the sticker. I was going to try and take it off and see if it says anything else one it. Does Atkins paint rotor housings silver and the side housings black?

I'll surely look for more identification marks when I get it to the shop to have it broken down. I looked all over and didn't see any other marks though.

jkep21 11-29-11 09:59 PM

Got some bad news about the motor I just picked up. Lance didn't know where the block came from. He said the ending of the punched characters ended in "ARS."

I can't remember every detail he said but he said there were only two possible reasons all the damage was caused. It was either someone tried to press in an already used stationary gear bearing in the rear or that the clearance was extremely too tight. The stationary gear worn completely down and cause the rear rotor to flop around causing all the contact marks on the rotor. The rear stationary gear bearing was also loose from binding up and I forget why he said that happened.

He said this would have been a perfect motor to send back for warranty as it was not built correctly, the porting on the irons was quite good, and one housing looked like it was a new replacement. He also said that the motor likely only had 100-200 miles on it since the rebuild as the motor had no build-up (besides bearing material) and that he could take the coolant seals out all in one piece.

Here are the pictures please let me know what you think as I'm actually curious who did such a cruddy job. I'll be having the one housing resurfaced if anyone is interested in buying it...

I've bought 3 motors now looking for housings for my 20b build and have had no luck so far. I can't believe how hard it is to find good shortblock engines to get parts from...

Sigh...


http://i1123.photobucket.com/albums/...1/718d0bad.jpg
http://i1123.photobucket.com/albums/...1/4ab69769.jpg
http://i1123.photobucket.com/albums/...1/83caa516.jpg
http://i1123.photobucket.com/albums/...1/4efb300f.jpg
http://i1123.photobucket.com/albums/...1/933aae27.jpg
http://i1123.photobucket.com/albums/...1/09afcc1e.jpg
http://i1123.photobucket.com/albums/...1/b67520e5.jpg
http://i1123.photobucket.com/albums/...1/27993cb4.jpg
http://i1123.photobucket.com/albums/...1/aafdeff5.jpg
http://i1123.photobucket.com/albums/...1/7c45371d.jpg
http://i1123.photobucket.com/albums/...1/9700f7b5.jpg
http://i1123.photobucket.com/albums/...1/9834d918.jpg

jkep21 11-29-11 09:59 PM

http://i1123.photobucket.com/albums/...1/d513e0c5.jpg
http://i1123.photobucket.com/albums/...1/5cc4bea1.jpg
http://i1123.photobucket.com/albums/...1/0c046f49.jpg
http://i1123.photobucket.com/albums/...1/1b7073c0.jpg
http://i1123.photobucket.com/albums/...1/c470ea81.jpg
http://i1123.photobucket.com/albums/...1/a68806de.jpg
http://i1123.photobucket.com/albums/...1/2451b493.jpg
http://i1123.photobucket.com/albums/...1/8ea6b65e.jpg
http://i1123.photobucket.com/albums/...1/d524b876.jpg
http://i1123.photobucket.com/albums/...1/57748f5b.jpg

jkep21 11-29-11 10:00 PM

http://i1123.photobucket.com/albums/...1/bd82aae0.jpg
http://i1123.photobucket.com/albums/...1/99812f51.jpg
http://i1123.photobucket.com/albums/...1/455fc219.jpg
http://i1123.photobucket.com/albums/...1/d6da2fc8.jpg
http://i1123.photobucket.com/albums/...1/5e1f20ef.jpg
http://i1123.photobucket.com/albums/...1/5b38df03.jpg
http://i1123.photobucket.com/albums/...1/6b30c044.jpg
http://i1123.photobucket.com/albums/...1/9d81d67a.jpg
http://i1123.photobucket.com/albums/...1/97d82570.jpg

hwnd 11-29-11 10:01 PM

I'm sure all the vendors will be jumping to claim that one :)

GoodfellaFD3S 11-29-11 10:10 PM

It could also be that the previous owner ran the engine low on oil, causing the bearing to spin and the ensuing carnage.

That secondary port looks alright I suppose (no bevel?), not one of our jobs. Any pics of the primaries? Also not a fan of 3mm seals, but to each their own :)

CrispyRX7 11-29-11 10:40 PM

Holy mother of.....that's a mess!
You're correct, finding good cores is becoming very tough.
Don't give up though, they are out there.

Regards,
Crispy

gracer7-rx7 11-30-11 01:19 AM

I like the compression and RPM numbers written w/ a sharpie

Banzai-Racing 11-30-11 05:16 AM

Those are Atkins stampings and compression notes. That does not mean that someone else has not been inside this engine since they built it.

The obvious reason that I can see for the engine failure is the thrust plate was installed upside down. This is why it is broken to pieces which lead to all the other damage. I see this all the time on DIY builds. It is a very simple part that can ruin a complete engine if not installed correctly.

Why don't you just buy 3 new rotor housings for your 20B? They are expensive but at least you will have the piece of mind that you have new parts in what is going to be an expensive build anyway.

jkep21 11-30-11 10:51 AM

I'm going to stop by the shop this weekend to see the upset in person. I think Lance sad something about the bevel on the thrust plate but I can't remember.

The reason I keep getting used motors is I was advised to get 3 matching letter rotors. At least I have some matching D rotors now. I'm going to have the sides and faces "Street Clearanced"

Lance does rotor housing resufacing so he said as long as theres no corner piece wear I will have perfect housings when he's done. I might post the other engine housings that I had him resurface to really show you how amazing it comes out. I got some Goopy housings and they come up short to Lances work.

I was told I won't need the engine balanced as I'm not going to be running low boost and not a really big turbo. I want the car to have 500-600 horsepower with a quick spool up. I have a late series eccentric crank so I was told I could run more boost but I'll be bankrupt when the motor's done so no need to try and blow it.

I actually got inspired by your 20b Banzi! Really nice job on it!

Banzai-Racing 11-30-11 12:48 PM

Those rotors are 3mm and have made some serious contact with the side housings.

Anyway, hope it all works out and you salvage enough parts.

j9fd3s 11-30-11 10:37 PM


Originally Posted by Banzai-Racing (Post 10881522)
Why don't you just buy 3 new rotor housings for your 20B? They are expensive but at least you will have the piece of mind that you have new parts in what is going to be an expensive build anyway.

that and you don't have to waste time and money tearing down junk used engines...

FD3S_wanted 12-01-11 01:07 PM


Originally Posted by Banzai-Racing (Post 10881522)
The obvious reason that I can see for the engine failure is the thrust plate was installed upside down. This is why it is broken to pieces which lead to all the other damage. I see this all the time on DIY builds. It is a very simple part that can ruin a complete engine if not installed correctly.

Do you care to elaborate on this? I'm about to re-assemble my engine and I don't see the error?

We are talking about the thrust plate from the front stationary gear? What do you mean by upside down? The face is not facing the correct side or the bottom of the plate should be on top. I inspected the thrust plate and it seems symetrical.

Thanks,

Alex

Gorilla RE 12-01-11 02:20 PM


Originally Posted by FD3S_wanted (Post 10883317)
Do you care to elaborate on this? I'm about to re-assemble my engine and I don't see the error?

We are talking about the thrust plate from the front stationary gear? What do you mean by upside down? The face is not facing the correct side or the bottom of the plate should be on top. I inspected the thrust plate and it seems symetrical.

Thank

Alex

The face is not facing the correct side. The inside diameter of th thrust plate is beveled in one direction. This bevel is made to "receive" the same bevel of that on the eshaft, during back and forth movement. ie "thrust" or "end play". When installed backward, it is essentially like trying to force a square "peg" into a round hole. Hence, the cracked thrust plate, such resulted in the "self clearancing rotors"! :)

-J

Banzai-Racing 12-01-11 02:52 PM

http://mazdatrix.com/pictures/b5-engft.jpg

1= Thrust Plate
4= Bearing Plate

I think you are confusing the two. The thrust plate in the above posted pictures is broken, it is not symetrical and was installed wrong.

Supernaut 12-01-11 10:38 PM

I am spartacus

RotaryEvolution 12-02-11 09:04 AM

it may have atkins stamped housings but i'm having a real difficult time believing that they installed that thrust plate backwards. after doing so many engines you just do it as second nature checking the bevel on the thrust plate, and the CAS drive gear.

basically what i'm saying is, could be possible it was built by another person while reusing the stamped housings.

if it only had a few hundred miles on it, why not send it back to the shop that built it in the first place? was obviously a workmanship issue which most shops should cover.

FD3S_wanted 12-02-11 10:02 AM


Originally Posted by Banzai-Racing (Post 10883445)
http://mazdatrix.com/pictures/b5-engft.jpg

1= Thrust Plate
4= Bearing Plate

I think you are confusing the two. The thrust plate in the above posted pictures is broken, it is not symetrical and was installed wrong.

Exactly, I was not looking at the good piece. Now I understand what you are saying.

In the FSM the "bearing plate" is called the "plate" and the "thrust plate" is called "thrust washer". I mixed these.

Thanks for the clarification...

Banzai-Racing 12-02-11 10:37 AM

5= Thrust Washer, located immediately under the counterweight in the diagram I posted and the FSM.

This would be why so many mistakes are made by people assembling engines for the first time.

Look at FSM pages C-59 and C-73

C. Ludwig 12-02-11 11:14 AM

Agreed, it's an Atkins build. I've seen those types of markings on their engines as well. Also impossible to place blame since it is a second hand engine.

The way I learned and remember which way the taper on that thrust plate and the CAS drive gear is oriented, is to assume it was put there to make it easier to install the part on to the e-shaft. All the parts slide on to the e-shaft taper first.

The rotors look like they're toasted.


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