SPZ510

Take a look at these pics and tell me if you see anything I should be aware of. Notice the scrapes on the rotor.? The side seals are stuck in there also. My friend said that when the bearings went the side seals got hammered into the rotors causing them to be stuck. What I'm wondering is the buildup in these areas. It was,nt more than a mile or two before I shut it down, if even that. Could those seals have been stuck before the meltdown? Oh, by the way the cause of the bearing failure was too little oil pressure with too light of a weight oil. 40 psi total at 5k. Just let me know what you think.

SPZ510

Here's the rotor. I can't seem to get the others down to size. If someone can help I can send them to you.

es

Download L view Pro trial:
http://www.lview.com/Download.htm

& reduce the size of the pics.

turbostreetfighter

if the side seals were stuck you would have been pressurizing the crankcase with boost your dipstick would have blown out and the engine would not make any compression. what weight oil were you using and type? be sure when you put your new engine in the car either replace the oil cooler or clean the hell out of it...all of that spun metel is sitting in there and will trap in the regulator. if you dont your new engine will not make 100 miles!


MWW

turbostreetfighter

i just looked at the rotor pic.... now you know why clearancing is so important! what kind of rpms were you turning that engine?


MWW

SPZ510

I was very carefull with my tolerances. A rotary engine builder that I know said that whichever stationary bearing failed, the side seals on that side of the rotor closest to it will literally get hammered into the rotor. Which is kind of what it looks like to me. I asked about clearances, if they were too tight and he told me to look at the corner seals for scratches from the side seal. Unfortunatly I had allready pulled everything up to the point that you see here. I'll check all the corner seals for wear marks. I looked up specs on this forum for side seal clearances. And I know you guys know your ****. Just kidding. I'm not sore. I believe the specs were from Crispeed. Maybe not. Use a .002" feeler gauge and make sure it has a good drag to it. Did that. My friend said that it would'nt even had lasted that long if the tolerances were off. I had 390mi. on it. From the nast marks on the rotor and the side housings what he said seems fair. The engine is not a turbo motor it's an old school bridgeport. Also check out the port timing and tell me if it seems ok. I started off with the RB template and another friend of mine modified the timing. Get back to me. Streetfighter, I'de value your opinion. Also Crispeeds.
I didn't know I was suppose to use 20-50. I had 10-30 in it from the start. From what I've been told you don't really have to by the expensive stuff for rotary engines. I was running 91 octane untill a everyone told me that these motors were designed in the 70's and run best on low octane gas. So I started using 89. Never had any detonation.?

SPZ510

Next.

SPZ510

Failed front.

SPZ510

Front stationary.

SPZ510

Bridgeport, full bridge, no turbo. Too broke to go turbo.
Don't mean to be a post *****, but I have no idea how to post all the pics in one post.

nimrodTT

10w30, eh? I'd venture to guess your oil pressure was caused by something more along the lines of a messed up a front cover o-ring. Were you at around 9k when the bearing failed?

SPZ510

I had a problem with the front o-ring for a while. Asked a bunch of people about it and even asked about it on this forum. Check the "Oil pressure range question" thread. No one ever gave me any straight answers and some people told me that "Yeah, sometime that just happens." Thanks alot!
And yes, just before this happened I was on the freeway running over 9k easily.
When I put this thing back together I will be much more aware of what my gauges should be reading. It's just a pain in the ***, cuz now I have to get some more housings and do all that porting over again since the old housing were damaged.
You guys running turbos are luck, you don't even have to port to make power! And even a street port would be more than enough on the street.

nimrodTT

Yeah, the o-ring usually slips off its intended position by just a little when putting the front cover on, then gets pinched when you bolt it down - results in a big internal pressure leak. Did you clean up the parts already? You should check your front housing and front cover to see if the damaged o-ring is there, that way you can be certain of the cause of failure.

EDIT: After going back and reading the other thread you already know about the o-ring problem. So let me just say that when you spin those bearings the e-shaft gets all nice and wobbly, that's why your rotor toasted itself on the side housing, and you'll want to check if the rotor hit the face of the rotor housing also.

now

iTrader: (1)

After looking at the pics I have to ask, did the rotors hit
the housings? you only show the sides of the rotors and
not the housings, but from the look of the stationary
gear bearings I would venture a guess that the rotor
did hit the housings and this is why the side seals are
stuck where they are. I have seen side seals stuck in
their groove from the smallest dent in the rotor face,
a dent so small that you wouldn't have noticed it, if it
were not for the side seal stuck in the rotor.
I have seen a motor run for 80,000k with the
o ring in the front cover 1/4 out of its hole, it had
really low oil pressure readings, and the only reason
i ended up rebuilding it was that a cooling o ring groove
failed.
when you are running high rpm's its really important
to have high enough oil pressure to keep the main
bearings oiled, and main bearings that are not to tight
to allow the oil to flow (under pressure) over the bearing
area.

my 2 cents
matt

SPZ510

Yes the rotors did hit the housings and they will now need to be replaced. I know at the time of failure my oil system was fine. Anything over 4k and I was seeing 100psi(gauge limit). I just think all the damage happened before I fixed the o-ring. Another thing my friend said was that if I had it idling for a long time with my o-ring like that, that would cause a failure. Coincedently, I had spent a long time tyring to get the motor to idle right. I'd say from the time I built the motor till now I had idled it for at least a total of 2-3hrs. in the driveway doing one thing or another. All this with less than 40psi.
Anyone take a look at the port timing and size yet that can give me some pointers. Should i go bigger? Should the bridge port be brought down lower? Maybe go further up on the main port? I'd like to make 240-250 at the wheels. I know the combo I had before it was good for at least 220rwhp if tuned. Can I gain another 20-30 with better porting. Also I polished the hell out of this thing and my car always ran rich, maybe I should leave it a little rough? Any thoughts?

javrosario

iTrader: (5)

Did you do the proper Oil mods, like three window stationary gear bearings, higher oil pressure, better oil pump. Stuff like that and clearance the rotors for those kinda of rpms?

SPZ510

The only oil mods that I did were the 17mm oil pump with hardened gears and i shimmed the regulators .250" for a 80-90 max psi.
No race clearancing as it is a street car and while it may be able to rev past 10k and will, it probably won't be taken to that extreme that often. Actually I want to get some sort of rev limiter to set at 9.2k.

setzep

I don't know... Looks like contamination to me. Whether it was solid form or liquid. I don't know how a bearing could turn into that if something didn't go through it.

nimrodTT

Without oil to guard against heat and friction the steel e-shaft will eat up a bearing real fast.

SPZ510

The front gear came off the shaft without the bearing. Since it had a bunch of grooves in it from failing it acted like threads not allowing me to just slide off so I used a screwdriver to open it up like that. It did'nt just come out like that, with the exception of the copper large flake coming out of the top there.
How did you post that pic like that without a link? That's what I wanted to do in the first place.

setzep

nimrodtt- duh, I guess I wasn't thinking about the low oil pressure thing...doh. my bad.

spz510- to post a pic you first do like you did by uploading it then go back and edit your reply and add a [ img ] [ /img ] but in between the [ img ] and [ /img ] you put the address of the pic and the pic will pop up like that.

Judge Ito

I see your using 12A side housings with your 13B engine. I also see that your using a a second generation eccentric shaft am I right? because if you are using a 1986 and later e-shaft you have to remember to plug the shaft in the centre(thermal bypass pellet area). If not you will loose alot of oil pressure and damage like this is done. Ill wait for your reply and Ill try to help you some more.

SPZ510

Judge Ito. From what I gather your an accomplished rotary engine builder, right? So you could look at my ports and tell me where to go with it.? I'm not asking for any trade secrets or anything just some advise. And yes, 86 e-shaft,83-84 12a sidehousings, 89-91 rotors,85 rotor housings.
I think I've got the whole oiling system figured out. Mazdatrix also said to use a solid thermal pellet. But at the time of failure, after fixing the o-ring, I was getting 100-115psi. I think all the damage was done prior to the 9k run. Maybe.

SPZ510

Wait, "Plug the shaft"? You mean not just the $18 thermal pellet replacement but a permenant plug? So that no oil whatsoever will get up front?

David88vert

We went through this problem twice on a TII. Make certain to check your counterweight when you rebuild the motor. Odds are that it is scored and will eat up oil pumps because you won't be able to get enough end clearance.