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-   -   Long sad story... Opinions on Diagnosis? (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/long-sad-story-opinions-diagnosis-796230/)

thewird 10-25-08 12:50 PM

Long sad story... Opinions on Diagnosis?
 
Well, I have to open my motor up again and I just want to confirm the diagnosis so I can sleep at night.

Basically, this is what happened... 2 months ago, I was seeing how far I could push the motor. Long story short, eventually it gave way at 18 PSi @ 12 AFR.

Ok, so now I had it rebuilt with brand new OEM housings, 20b rotors, and NRS one-piece ceramic apex seals (the spotted ones). After a 1,000 km break-in during a 2 day period on country roads only, slowly increasing RPM's and boosting 3-5 pounds every 10-20 km for one pull of whatever RPM range I was working with at that mileage the car was tuned to 16 PSi at safe <11.5 AFR. Made good power and ran well and I planned to keep it that way until I got my A-Spec 500R-SP turbo.

So I took it to its first track day for testing the new motor. Motor ran well and pulled harder then it ever pulled before even when I tuned to 18 PSi (higher top speeds on the straights by about 15-25 km/h). The special porting that my mechanic did made a huge noticeable improvement. Anyway, I noticed something strange that day. Whenever, my BOV would go off, I could see white smoke come out the hood. Since, it was a cold day I assumed it was just from the cold.

After talking with Bryan from BNR though after thinking about it being the turbo's, we diagnosed it was probably the turbo's going out. One of the apex seals must have hit the hot side fins and the rotating assembly was out of balance slowly wearing the oil seals. Since my 500R-SP was due in 1-2 weeks, I just decided to keep driving it and if the turbo's die, they die since they were going to be repaired anyway.

Well, our assumptions about the turbo's dieing was correct. One evening when I went out for a midnight drive, the car stopped boosting entirely and was making a wooshing sound when I tried to boost (turbine stop probably). It still ran perfectly fine, just without boost. So I turned around and started pampering it home. After about 5-10 minutes, the car started boosting perfectly normal again. I continued going home and after about 10 minutes, I started realized I was giving the car more gas to keep it going, the car was losing power. I look at my boost guage and it showed 6 PSi while cruising. I let off the gas and press the clutch to see if the car would idle. The car stalled and I pulled over on the highway. Tried starting the car and it would not start but would seem to almost catch sometimes.

I tried diagnosing the problem looking for any vacuum lines that may have popped off and such with light for my phone. I then thought, the fuel pump wiring went funny again which was unlikely but I thought i'd give it a shot. Wired the pump directly to the battery and tried to start the car again. No difference at all so it wasn't the fuel pump. I checked the dip stick and noticed it was half oil and remember it being full. At that point I pretty much knew it was the turbo's.

So I waited for 20 minutes to let it cool down and then decided to try start the car again. It did start but wouldn't idle without some gas. I happened to be 4 minutes away from a friends house, so I quickly decided to bring it there since it was running. I drove it there leaving a huge trail of smoke behind me (burning oil). I parked it in front of his house and slept until morning (didn't want to wake him).

The next day we took of the turbo's and confirmed the primary turbo was blown. Both rotors had great compression but something was funny. The front rotor spark plugs were wet and the rear one's were dry. We just assumed it was the oil and left it at that.

Fast forward 2 weeks... 500R-SP turbo comes in, we do the single turbo conversion (finished last night at 7pm). We bring the car outside because we knew it was gonna smoke like a mofo and I start the car. It started ok but wouldn't idle on its own (sounded the same as on the highway). We waited to see if it would clear out. It didn't and kept running in the same. Maybe the front rotor wasn't firing because of the plugs. So we put new plugs in and try again. Exact same result. We try cranking the motor with plugs out and notice oil and fuel is spitting out of the plug holes. We kept cranking to see if it would go away but it kept coming out.

We think about it for a bit and my mechanic thinks that what happened is there was so much oil coming into the chamber from the turbo's that the rotor hydro locked and since oil won't compress, it found its way to the weakest link, the oil seals... So now its assumed the o-rings are damaged but can't be sure until we open the motor and see whats up.

So is this a fair assessment given the train of events? It sounds like that's what happened. Is there a possibility that anything beyond the oil seals was damaged? My mechanic suggested the apex seal springs may have flatted too but thats no big deal.

I guess we'll see when we open it up but I just needed to get it out. I was getting ready for a big track day event today and then this happened... And now winter is almost hear and I might not be able to drive the car before snow hits... No track days either... It will take 1-2 weeks to open the motor up and fix whats broken... I don't imagine the cost will be too great if assumptions are correct...

Anyway, thanks for reading if you read it all lol...

thewird

G's 3rd Gen 10-25-08 03:36 PM

Sorry to hear about that. Hopefully you can get it back together to give us some feedback on the SP version. Good luck. G

2007 ZX-10 10-25-08 05:17 PM

pardon my ignorance but are these BNR Stage IIIs? why did they take a dump at 16 psi? how many miles were on them?

thewird 10-25-08 05:29 PM

Because they must have been damaged when I blew the motor by an apex seal. There was no visible damage on them but there must have been a bit missing so the whole rotating assembly was out of balance and eventually wore the oil seals.

Mileage doesn't really matter with my car. I track it almost every weekend so the car is working at max for hours. I only had them installed in the spring but they've seen at least 15 track days and I don't turn my boost down at the track. They were at 18 PSi before the motor blew and 16-17 PSi for most of the year. They had at least 20,000 km on them as well during this year.

thewird

7_rocket 10-25-08 05:45 PM

This young man likes to go to the track every weekend and then drive the car on the street as much as he can. Sorry sir, you can't have your cake and eat it to :goodrebuild:

thewird 10-25-08 05:54 PM

Tracking has nothing to do with the events that took place.

Run dangerous tune, 18 PSi @ 12 AFR with Sunoco 94 --> apex seals go boom after 4 laps at Mosport
*fine, it was my fault, rebuild
But wait, the turbo's happened to be damaged so they blew after 2,000 km
*no problem again, I was expecting the 500R-SP in 2 weeks
But to top it off, the turbo's leaked so much oil before the car was shutdown that they did internal damage due to hydrolock... (assuming assumptions are correct)

Maybe my car hates me for blowing it up knowing that I was running a dangerous tune... Devil 7 lol

thewird

2007 ZX-10 10-25-08 06:43 PM

FD money pit...

proz07 10-25-08 11:22 PM

why have you not done a compression test yet? i can see a rotor not firing being way to much oil in the chambers snuffing the spark. but the shear amount of oil that would need to be injected to hydrolock ???? you would have seen massive plumming smoke before this. i suggest a compression check and if nothing is out of the ordinary clean the oil out possibly with a water treatment when you get it running on the one rotor. but y guess do a compression check even a poor man version of it.
z

thewird 10-25-08 11:29 PM

We did an ear compression check. Both rotors puff nice and strong on all 3 strokes. The plugs get instantly fouled with all the oil. When the plugs are out, you can clearly see oil coming out of the plug holes.

And, yes there is a ton of smoke coming out. The car had less then a quarter of oil left when I checked after stopping and distinctively remember it being full (since it was a new build, I was always checking).

thewird

proz07 10-25-08 11:44 PM

i guess my ears arent as calibrated as yours i use a gauge. at the least try a can of carb cleaner down the LIM while cranking to clean that oil out with your new plugs. if not ill be interested to see the outcome of this. Please update when you find out more. it just sounds like guesses at this point.
z

thewird 10-26-08 12:18 AM

Yes, it is guessing. But the known facts are primary turbo blew and the oil spews out of the spark plug holes. Also, we ran the car for 5 minutes to see if it would clear up but it did not.

My mechanic is pretty convinced that is what happened but we were all tired and in a hurry due to the track day the next day. I'll see on Monday but I pretty much agree with the existing diagnosis unless something changes on Monday. Also, need to find out how long it would take to fix assuming its only the o-rings >.<

I'll definetely update as soon as I know more.

thewird

IAN 10-26-08 09:50 AM

On the Ottawa Team Race FD when the oil seals went it pressurized alot of oil into the catch can and the car smoked. I don't think alot of oil actually made it into the combustion chamber but if its your oil control ring who knows. Keep us posted as you will find out soon enough within the next couple of days. Hopefully none of the bling parts are damaged.

Hope its all good and we all make it to DGRR2009.

twokrx7 10-26-08 10:53 AM

I too would expect the motor to pressurize the crank rather than the oil system pushing oil into the combustion chamber. I suggest you make sure the intake trac is emptied of oil ... IC & piping, UIM/LIM, etc. then do a real compression check.

gracer7-rx7 10-26-08 11:04 AM

If one rotor's plugs are clean and the others are oily, I'd look into problems with the OMP, OMP lines and oil squirters. I'd also look into ignition problems with coils and plug wires.

mdpalmer 10-26-08 12:25 PM

Sorry to hear bud, at least you had some hard miles on your setup. Best of luck to you, at least you have a new turbo to play with :)

Trots*88TII-AE* 10-28-08 01:08 PM

During cranking, I doubt the oil pump will put out more PSI then the combustion chamber, so I agree, check compression with a gauge, because if it was putting out 100+psi in the front housing, there's no way the crankcase oil would be pushing itself in in that large amount! I second the OMP check too, personally if it was my motor, I'd do everything and anything possible check-wise before tearing it apart, it's a hell of a lot cheaper to find something else wrong before it's torn apart! Good luck with it, very sad that you didn't even get a chance to push that 500r SP after such a patient wait! :*(

Dudemaaanownsanrx7 10-28-08 05:07 PM

even with the turbos shooting oil into the intake tract because of a blown turbo, i doubt it would be enough to hydro lock the engine and force the oil control rings into failure. The oil would be divided among both chambers and even if one chamber was not firing it would still just be pushed around and then shot out of the exhaust port.

I could see an oil control ring being an issue, this does happen. though i doubt it would be caused by this.

I agree with doing a real compression test. And you also need to verify that you have spark on all 4 plugs, and that your 2 primary injectors are firing. Did you dump out any oil in the intercooler? also check that the check valves in the oil metering injectors have not failed.

You should also determine which rotor its running on, cause it sounds like its only running on one. If you can pull the front injector clip on the primary while its running it will help determine which chamber is the issue. pull the front if it dies its probably the rear. pull the rear if it runs the same, then the problem is on that side. if you cant get to the injectors then pull the plug wires.

a couple times i had one rotor flood on me, and the car was running on one side, i just pulled the injector clip on the flooded rotor and reved the car up to 2500 or so and held it there for a little bit then reconnected it and i could hear the engine pick back up like normal. maybe something similar is going on with yours between all the oil fouling things up and then the fuel still being injected.

DCrosby 10-28-08 07:29 PM

Not that I have an answer, but this sort of thing has happened to me often, I notice something failing, then I stop the car try to fix it, and nurse it back, and in that I do more damage, than was present when I was at the side of the road. So now I just call AAA or Lock 'er up and hope someone steals her so I can write her off and get a new one blaming the issues on the thief :p: (Not Really but sometimes I feel like that would make for a better scenario) :D

mono4lamar 10-28-08 11:03 PM

You need to take some of the advice in this thread. There's some good stuff so far. Make sure the intake piping is cleaned out. Look for puddling in the TB and UIM. I really doubt you hydro-locked the motor with oil. If you hydro-locked it you would have noticed it. I would look into the OMP. If you can get to the vacuume lines to the top of each I would cap them off and disconnect the OMP. The other thing you HAVE TO DO is get a compression check. Please first take out all the plugs and put a charger on and cycle the engine for 30-40 seconds to clear out any oil. Get the compression report and come back. As for the idle problem you could have a sticking or stuck injector. I had an injector once that would stick whenever it wanted causing you to have to keep the car running by throttle. Take some careful steps and report back...

FearNoPiston 10-29-08 01:15 AM

Man I was excited to see your car all tuned...good luck sorting it out.

-Chance

Terrh 10-29-08 01:23 AM

I can't see it hydrolocking a rotor no matter HOW bad the oil seals to the turbos are.

You could probably plumb the oil feed line for the turbos directly into the intake manifold and not hydrolock the rotors.

Once, a LONG LONG TIME AGO, I MMO'd my car with a big vacuum line and basically it sucked an entire bottle of MMO dry in less than 10 seconds. SMoked like crazy and stalled the engine, I got it fired up after cleaning the plugs and it ran fine. Smoked for about 30 minutes though. And my whole street smelled like burning peppermint.

it taking 6PSI to cruise sounds like something else was wrong. You said the engine sounds weird... weird how?

What were the compression numbers?

Did you find oil (large amounts) in the exhaust manifold or on the turbos? What about in the intercooler piping and etc..

Anyways, if you can get it to run it should be easy enough to figure out if it's still losing oil . Top it up to EXACTLY the full mark and take it out for a drive.


btw, you're taking me for a ride in your car on the way to DGRR or something next year. Must go for a ride in a fast FD. It's been too long.

thewird 11-03-08 03:52 PM

Ok, finally tested the compression. The front rotor pulses 35 PSi on ALL faces and the rear pulses 75 PSi on all faces with a non-mazda compression tester. Another guess is that the apex seal springs have been flattened. Again its a guess so won't know until we open it up. Should be pulled out and open by Wednesday.

I almost thought it was fixed after the compression test cause it was able to idle on its own with fresh plugs for about 5 minutes and then it started idling sloppy and died after some revs. Was probably from cleaning out all the oil and fuel before the test.

thewird

Trots*88TII-AE* 11-03-08 05:12 PM

Good luck with it, hopefully it will take minimal parts to get back and running! Really looking forward to hearing how that 500R SP does.

thewird 11-03-08 08:57 PM

I was really looking forward to it too... I hope nothing expensive is damaged either but we won't know until we open it up. The weird part is the engine is really smooth, just that something isn't right.

thewird

mono4lamar 11-03-08 09:34 PM

Did you do the build? I'm sorry to hear the compression is low in the front rotor. Was is it 3 35 pluses with no skips? Did you let the needle close and build up to the highest pressure? I hope for some reason that your seals are just shot and that the housings are still good. What seals were you using?

thewird 11-03-08 10:06 PM

Motor had a little over 2,000 km before the turbo's blew. It's 35 even pulses with no skips at all which is why I find it strange. I hope its not the seals lol, they're NRS ceramics. That would cost me more then a new OEM housing o.O

thewird

Trots*88TII-AE* 11-04-08 01:05 PM

If it was a seal blown, I wouldn't think it would make 35psi in even pulses, you would at least have one face making more then normal, and I doubt all 3 seals would go equally, hopefully just springs are the case.

thewird 11-04-08 02:15 PM

I hope its something simple like that too...

thewird

Speed of light 11-04-08 02:25 PM

Given the amount of oil consumption and the balanced compression, I think you're gonna find a failure common to all faces (on one of the sides). And it's not going to be the apex seals or springs.

thewird 11-04-08 02:27 PM


Originally Posted by Speed of light (Post 8693509)
Given the amount of oil consumption and the balanced compression, I think you're gonna find a failure common to all faces (on one of the sides). And it's not going to be the apex seals or springs.

Any guesses to what it could be? 5 bucks to the person who guesses it right lol. It might not be leaking oil anymore, I think there was just so much oil in there that it took more then running it for a few minutes to clean up.

thewird

thewird 11-07-08 02:18 PM

Well boys and girls, the original assumption was correct. The oil seals and side seals got busted to hell taking the side housings and rotors with them with. Apex seals, bearings, housings are fine but going to need front and middle side housings as well as new rotors for both (My new 20b rotors toast :wallbash:). My mechanic said he would never had imagined it would be this bad and he has never seen anything like it. Also, was really disappointed because of all the hard work my mechanic put into those ports...

I'll post pics in a sec...

thewird

thewird 11-07-08 02:30 PM

Pics taken with my phone camera....

*Click for high-res
http://thewirdsdomain.com/rx7/engine/11-07-08_1220s.jpg
http://thewirdsdomain.com/rx7/engine/11-07-08_1221s.jpg
http://thewirdsdomain.com/rx7/engine/11-07-08_1313s.jpg
http://thewirdsdomain.com/rx7/engine/11-07-08_1314s.jpg

thewird

GoodfellaFD3S 11-07-08 07:46 PM

Yikes! Looks like you ran your oiling system waaaay too hot.

JDK 11-07-08 08:31 PM

Or...lack of oil due to blockage or low oil level, which took out everything including the turbo's

GoodfellaFD3S 11-07-08 08:36 PM

How did your oil pickup look?

Dudemaaanownsanrx7 11-07-08 09:01 PM

you're not having very good luck with your engines. Although the first engine was to be expected, any idea what happened with this one? Are plates like that reusable?

thewird 11-07-08 11:03 PM


Originally Posted by Dudemaaanownsanrx7 (Post 8703823)
you're not having very good luck with your engines. Although the first engine was to be expected, any idea what happened with this one? Are plates like that reusable?

The plates are not reusable since they have been heat scored.

thewird

proz07 11-07-08 11:41 PM

hey sorry to hear its not so good wish i could see the pics right now but alas im currently deployed and its filtered :(

z

2007 ZX-10 11-08-08 02:33 PM

look for a used Noble M400 :)

KKMpunkrock2011 11-08-08 02:55 PM

ouch man, that sucks, good luck with your next set.

Trots*88TII-AE* 11-10-08 10:50 PM

:( those pictures make baby jesus cry

IRPerformance 11-10-08 11:10 PM

That oil control ring looks like it was installed incorrectly. Hard to tell from the pic, but it appears as it was torn as it was put in. Is the ring still pliable? Oil control rings rarely fail expect due to age, or improper assembly. Side seals mostly fail if clearanced wrong or the port is shaped wrong. Still, looks like you had on oil starvation problem. How are your oil coolers? Was the oil pump replaced or at least inspected during the last rebuild? Make sure the key is there. It is very easy for the key to pop out and slide behind the gear, and you won't even notice.

thewird 11-10-08 11:20 PM

Another theory from Bryan at BNR Turbo's is that the stock BOV spring got stuck open and the turbo's overspinned and failed starting the oil leak which eventually led to the low oil level causing the engine failure. This theory does seem to match the series of events that took place before I noticed the engine losing power which was the turbo's losing boost and I'd hear a wooshing noise when I tried to go into boost. The boost came back on after I hit high RPM and WOT which at that point is most likely when they overspan and started the oil leak. Again, this is just another theory.

Maybe, once he opens up the turbo's we'll know more of what happened.

thewird


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