Howist going

I Pulled my 13b out on my 626 due to low compression in the rear housing. The compression was 110psi and 50psi on the front. So ive just finished pulling the engine down, ready to rebuild. Ive taken photos of every plate/housing/rotor seal etc to try and get the most help and advice when it comes to rebuilding a 13b as it is my first.

Engine Specs:
*Series 5 RX7 Housings " Can anyone tell me if the plates are S5 ?? "
*High Compression rotors
*13B Bridgeport
*Carbon Apex Seals
*Race Oil Pump
*Full Rebuild 5200kms ago
*48 IDA Webber
*K&N Air Filter
*9mm Eagle Leads
*Electronic Dizzy Locked
*Gilmour Pulleys
The Car was tuned at 198hp @tw


*The housings look good as gold, no chrome is coming off them very very minimal scoring

*The Rear plate and centre plate have got some marking on them. Looks like some of the side seals has marked the plates.
*The front plate is in better shape.
*All 3 plates have have a small "line" of wear along the intake side of the plates

*Both the rotor bearings look absolutly buggered!! ( But only rear failled ... )
*There is wear on the "rear" rotor on all 3 corners, front and back .( Skuffing )
*Side seals and Corner seals were worn right down on 2 of the corners , front and back.
*The "front" rotor and seals are all in good looking shape
*Apex seals and spring look all good.
*Oil Control Rings and Springs look good aswell

* The E-Shaft has a small amount of a bronze marking on the rear lobe
* The rest looks like it wont be a problem

I plan on measuring the wear on the plates and rotors and all the seals, when my DTI and Vernier decide to turn up in the mail haha

So now ive pulled it down and taken photos , i want to see what you guys reckon about the parts i have , and what you would recommend me to do.













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First off very very nice car, its killer!!

I dont know if I'm gonna be the help your looking for but, It doesnt look like a complete disaster but you might want to change out some parts. IMO the eccentric shaft's gotta go or the pictures just look worse than what it is. But thats just me. You might be able to have it resufaced, I dont know.

Do you know if it was running lean or hot? I colapsed a few of my seals springs that way. Mine looked just like you side seals. Cant really tell if that one picture has a broken piece of a seal in it or not.

Your plates look like you might be able to have them cut within spec's. Its difficult to judge the depth of the scrapes. I would try some really really fine sand paper to smooth out the surfaces of the rotors.

Check your oil pressure regulator to see if it has any blockages from the bearings breaking down. And they oil galleys on the e-shaft too.

I might be missing somthing but from the the pictures, I think its salvageable.

 

from a quick glance....

new bearings, new eccentric shaft at the minimum....

housings look DECENT, but would need closer look

 

looks like there was a lack of oil problem and the rotor's sides made contact with the Side iron's. get a used shaft, they're cheap at 50-100 bucks new set of bearings all the way down will be about 105.( dealership) you maybe able to sand the irons down to useable, make sure you check the rotor width. VS the rotor housings at A vs B,C,and D, per FSM. ALSO, are the side seals stuck in the rotor or and you get them all out without brakage? it looks like the tips are flat near the corner seals.

 

I am an amateur at building engines still, but have you actually measured the step wear on that iron? I would just clean everything really good again and take ALL of the measurements and compare them to the specs in the book. It's the only way to really know in my opinion. Plus you'll learn a lot no matter if they are in spec or not. Did you buy one of the dvds? That really helped me a lot, I bought the rotary aviation version, but there are others too.

 

You need to figure out why it failed. Is the eshaft thermal pellet still in there?

 

Hay there.
Haha cheers , i havent heard any bad comments about the car so far , even thou it is 116dB at idle =D

Yeah i think the e-shaft looks worst than it is. Im sure with a polish it will come up fine. but will measure it

The car ran pretty rich all the way through the rev range. ( A/F Gauge )

Whats usually cause the bearing to poop the bed like they did? Detonation/Pre Ignition ? The side seals and corners seals were pretty much worn right down to the rotor on one side

 

Hay man. When looks at housing ? what are the main things to look for? and is the FSM the best place for info about the tolerances etc etc?

 

Lack of oil ..... hmmm definaltly had oil in the sump, funny thing is that the last owner swore by using 10w-40 Diesel oil........ Could this of helped the bearing **** the bed? lol by " VS the rotor housings at A vs B,C,and D, per FSM " you mean
? ... And yeah the side seals on 2 of the sides were worn right down , but i got them out along with the corner seals

 

Any ideas? I had a problem with the Premix when i first got the car......
In NZ we have 91 , 95 , and 98 Octane. When i picked the car up i put 200ml to 10L of fuel. The car had a ruff idle but when sweet as. I dropped back the premix to 110ml per 10L of fuel. After driving the car around abit in my home town , i put 95octane in a 110ml. And not so long after the failure happened. I dunno if its connected but people out there would have more idea on why the engine has gone bad. Is the Thermal Pellet also referred to the "bypass valve and spring " that comes out of the front of the e-shaft?

 

the "bypass valve and spring" may have failed. Oil pressure and bearing problems are not that common on rotaries. Most failures are from worn out seals unless it is some kind of catastrophic failure (detonation or overheating)

 

Buggar ...... Double post

 

Is there anyway to check the valve? I did notice i has been spaced out with a Nut ..... so im guessing the valve wouldnt be the problem ? I orginally thought it was detonation due to my Premixing issues. But the car never got to extremely hot, a few times 100oC doing 3rd gear burnouts with 3 Fans cranking