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-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   How a 400k motor look like inside! (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/how-400k-motor-look-like-inside-719233/)

DrBlazeMdoc 01-07-08 07:58 PM

How a 400k motor look like inside!
 
ok heres the update... this motor has 400k motors until the seals went out the door. I finally cracked it opened and let me tell you, its a mess! The corner seals on some of them actually has carbon build up so bad it has little cylinder carbon in them. So much carbon deposit was on the face of the rotor dude u literally have to pick it off! even the oil seals was so brittle when u take them out they literally break off, even the side seals broke when they came out! the water jacket was held together by pressure, when u took the plates off some of the water seals broke off and stuck onto the housing! the funny thing this motor never burned up water or oil!!!


http://i238.photobucket.com/albums/f...2008/rotor.jpg
http://i238.photobucket.com/albums/f...ran2008/r8.jpg
http://i238.photobucket.com/albums/f...ran2008/r6.jpg
http://i238.photobucket.com/albums/f...ran2008/r4.jpg
http://i238.photobucket.com/albums/f...ran2008/r3.jpg
http://i238.photobucket.com/albums/f...ran2008/r2.jpg
http://i238.photobucket.com/albums/f...ran2008/r1.jpg

to be continue.......
follow up with parts all clean and part inspection.
rotary ressurected soon rebuild...

manslayerx9 01-07-08 08:01 PM

miles or km

DrBlazeMdoc 01-07-08 08:02 PM

http://i238.photobucket.com/albums/f...ran2008/r9.jpg
piece of dookie 4 u guys lol
http://i238.photobucket.com/albums/f...ran2008/r5.jpg

DrBlazeMdoc 01-07-08 08:03 PM

miles CA bay area

manslayerx9 01-07-08 08:04 PM

wow and that stuff is from the coolant passages??

Trybal 01-07-08 08:12 PM

how did that thing even run? lol

nkeehn 01-07-08 08:15 PM

My GF's car is almost to 200K, I wonder how bad it looks...

blmcquig 01-07-08 08:17 PM

wow, 400,000 miles on one engine? that seems unlikely. but, ive seen stranger things. i guess props for keeping it running that long! youd have to think they would be almost, if not ALL highway miles to go that far.

RETed 01-07-08 09:02 PM

That little cylinder of carbon is actually a rubber plug in the corner seal...

I really don't see anything weird about what you found.
I'd expect seals to be brittle with that kinda mileage...


-Ted

DrBlazeMdoc 01-07-08 09:23 PM

this 13b was in a car that had 1 owner with documentation from day 1 from the mazda dealer lot to 20 years of service from rick's rotary in pleasanton CA. that mud was in the coolant passages. tremendous amount of carbon build-up, other then that yes highway miles & local driving. talk about getting your money worth! Even the car itself with its orginal paint job still looks like its off the showroom, been garaged all its life!

slo 01-07-08 09:28 PM

Ive taken apart some 220+ K motors and none of them had any mud in the coolant passages.

RETed 01-07-08 09:32 PM

I've taken apart motors with "only" 100k miles, and they had that mud / sand in there.
It's easy to do - don't flush the coolant properly.

That mud is aluminum oxide that's from the aluminum parts inside the cooling system (rotor housings, water pump housing, radiator).
There are dead zones in the water jackets that have very little flow.
This is where this mud typically builds up.


-Ted

Akagis_white_comet 01-08-08 03:11 AM

Wow, I think you set a new record for highest mileage on a vehicle and original engine before a rebuild. Seriously, you might want to see if you can get in the Guinness Book of World Records, because that is incredible. I knew that rotary engines were long-life engines (if treated right), but this is ridiculous!!!

Boostmaniac 01-08-08 06:54 AM

Props to you my man!

arghx 01-08-08 07:02 AM

^^ maybe for a rotary, but I heard on NPR years ago about this volvo that went like 800,000 miles on the engine or something. car had over 2 million miles on it.

lt1_rx7 01-08-08 07:21 AM

my dad was telling me about a mustang in WNC that has 600k original miles on it...but 400k on a rotary is damn impressive

scrip7 01-08-08 08:44 AM

Holy bejeebus man. Definately should contact someone from Guiness. You may need to obtain the maintenance records from the original owner or the dealer in Pleasanton if you can. Do it. I can't imagine there being very many parts within specs, perhaps an iron housing or two. Excellent find bro.

FuStEr 01-08-08 10:16 AM

o_0 dang

Terrh 01-08-08 10:21 AM

a 400k rotary is far more impressive than an 800k volvo.

Houpty GT 01-08-08 11:40 AM

If I recall correctly the 1966 Volvo 1800s had a rebuild at 600,000 miles and currently has over 2,600,000 miles on it. It is the original owner and he pretty much just drives the car from show to show now. The Volvo also had very little need of repairs. Plenty of well built cars reach 400,000 miles. If someone brags about having 200,000 on a car I laugh at them because I have had many cars with well past that. I would not have thought it was possible on a Wankel rotary engine though.

"The engine has been rebuilt once at 680,000 miles..completely. The head has not been off since and that was in 1978. I had the work done by the same dealer that sold me the car in 1966 and they still service it today. I had it done as preventive maintenance as I never heard of an engine that could last that long." http://www.cincitdi.com/odometer-aim...ion-mile-volvo

RotaryResurrection 01-08-08 12:47 PM

I dont see anything all that out of the ordinary here. The cornerseals have these rubber plugs inside them that harden at about 10k miles, so that is what you are seeing, not carbon. That chunk of mud is about twice the size of normal, but indicates poor coolant flush habits over the life of the engine, and has nothing to do with how it runs. It is a result of an iron aluminum block.

When a lot of carbon is present it is not unusual to break or bend side seals upon disassembly.

I have seen that amoutn of carbon or more form on 20k mile rebuilds when cheap gas and cheap oil are run and oilchanges are neglected.

IT is completely normal for old coolant seals to be brittle and shred into pieces during disassembly. Only coolant seals that are from a recent rebuild, say 2 or 3 years old or less, will come out in one piece...sometimes not even then.

w0ppe 01-08-08 03:38 PM

So it's like... After running for a LONG time, the carbon made their OWN SEALS!!! Amazing even though it looks like it's been through Hell and back.

RETed 01-08-08 03:46 PM


Originally Posted by w0ppe (Post 7713958)
So it's like... After running for a LONG time, the carbon made their OWN SEALS!!!

NO.
As I and others have mentioned, the OP didn't realize that a rubber seal actually exists inside the corner seal.

Chunks of carbon have very little compressive strength, so it cannot function as a seal.


-Ted

speedy_az 01-08-08 06:23 PM

Whats the best way to keep carbon build up out of your motor? Is there a fuel additive that is wont harm my rotory motor?:beer:

RotaryResurrection 01-08-08 07:12 PM

daily redlining/hard driving (not all the time, but at least a couple of WOT runs per trip), frequent oil changes, and perhaps the occasional water cleaning treatment (per writeup on my site) making sure not to let in too much water at once (too much can dilute the oil supply).


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