Confirmed : NYCGPS's Motor is dead~
04-02-2009, 07:03 PM
#26
rofl.
*sigh*
I mean, Sooner or later All motor will go this route.
Just the matter of time ... mine is a bit sooner thats all ...
No way to tell, unless ...
Thx. 
*sigh*
Just the matter of time ... mine is a bit sooner thats all ...
It would be good to see if the side seal springs are failing like they are on the race motors. It would be really great for all involved if Mazda could start breaking down the failure modes and causes so the community could do the right thing to preserve our motors.
Premix will help the apex seal issues but not the side seal spring failures. Only a new part number will help that.
Premix will help the apex seal issues but not the side seal spring failures. Only a new part number will help that.
wow i woulda gone ape nuts if i got 120 miles per tank, that is NOT normal
for reference, my '04 with 89700 miles usually gets 240 miles before the fuel light comes on in mixed 50-50 driving
at least you're patient about the car, i'll give you that, lol
best of luck with the new motor, and tranny too!
for reference, my '04 with 89700 miles usually gets 240 miles before the fuel light comes on in mixed 50-50 driving
at least you're patient about the car, i'll give you that, lol
best of luck with the new motor, and tranny too!
04-02-2009, 07:15 PM
#27
Administrator
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well, better now then a few years down the road when the warranty is gone. Fortunately it seems as though the remans coming to us these days are pretty damn good.
I'm actually happy for you man, it'll be nice to get you a solid engine!
I'm actually happy for you man, it'll be nice to get you a solid engine!
04-02-2009, 07:49 PM
#28
Certified Mazda Tech
as a note BTW, we comp. tested his motor not too long ago, front rotor was weaker then rear but still good. Things seem to have gone downhill somewhat fast at least on the front rotor, rear rotor hasnt budged nearly as much.
None of the signs of a sideseal failure.
The lean condition leads me towards apex seals and charge contamination causing excess air in the mixture in the combustion chamber, just enough air to be compensated for without being too lean.
Looking at the face numbers obviously one face is a lot worse then the other 2, altho theyre not too far behind.
I'll try to take the best pics i can inside the exhaust ports, i have a video snake i can slide thru the spark plug holes too so we can check carbon conditions but she's been decarbed at least once, maybe more, i was hoping for just a stuck seal but went old school after the comp test (ATF and a steam bath if you must know lol) and nothing improved.
kevin.
None of the signs of a sideseal failure.
The lean condition leads me towards apex seals and charge contamination causing excess air in the mixture in the combustion chamber, just enough air to be compensated for without being too lean.
Looking at the face numbers obviously one face is a lot worse then the other 2, altho theyre not too far behind.
I'll try to take the best pics i can inside the exhaust ports, i have a video snake i can slide thru the spark plug holes too so we can check carbon conditions but she's been decarbed at least once, maybe more, i was hoping for just a stuck seal but went old school after the comp test (ATF and a steam bath if you must know lol) and nothing improved.
kevin.
Last edited by teknics; 04-02-2009 at 07:51 PM.
04-02-2009, 07:56 PM
#29
Power!!
Thanks for the input Kevin. It's great to have someone that is hands on and knows what's happening. The fact that you mention the motor went down hill fast suggests a catastrophic failure as opposed to something wearing out. Just my $0.02
Also you mention 1 face being worse than the rest. IMHO That seems like it would be side seal related rather than apex to me. I would think if it's apex you would see 2 faces low since they share an apex seal.
I can't wait to see your video and pics.
A picture will speak more than thousands if internet theories.
-Shaun
Also you mention 1 face being worse than the rest. IMHO That seems like it would be side seal related rather than apex to me. I would think if it's apex you would see 2 faces low since they share an apex seal.
I can't wait to see your video and pics.
A picture will speak more than thousands if internet theories.
-Shaun
04-02-2009, 08:22 PM
#33
Certified Mazda Tech
Thanks for the input Kevin. It's great to have someone that is hands on and knows what's happening. The fact that you mention the motor went down hill fast suggests a catastrophic failure as opposed to something wearing out. Just my $0.02
Also you mention 1 face being worse than the rest. IMHO That seems like it would be side seal related rather than apex to me. I would think if it's apex you would see 2 faces low since they share an apex seal.
I can't wait to see your video and pics.
A picture will speak more than thousands if internet theories.
-Shaun
Also you mention 1 face being worse than the rest. IMHO That seems like it would be side seal related rather than apex to me. I would think if it's apex you would see 2 faces low since they share an apex seal.
I can't wait to see your video and pics.
A picture will speak more than thousands if internet theories.
-Shaun
With the way combustion happens in the rotary and the direction of the flame front typically the front apex seal has the greatest effect on a "chamber's" compression. Aka each face has a leading and trailing apex (just like your plugs lead is bottom, trail is top) The "leading" apex seal is more important for compression of each face because the flame front begins, and is strongest, at the leading edge of the rotor face, as it expands upward it slows and loses force. Also the trailing edge of the rotor face is less involved in "spinning" the leading face however is where all the force of combustion is focused on as it spins the rotor to get to the next face.
So typically lets say that Rotor Face 1 one worn/bad apex seal on the leading tip and all other apex seals are fine. Rotor Face 1 will have low compression, the next face will be fine, the 3rd face will generally have a compression number in the middle of Face 1 and 2, since it's trailing apex seal (face 1's leading) is bad and losing what you could call waste compression/combustion (most force exerted on trailing side of rotor is weak so the rotor can spin the right direction with no force acting against it.
Probably best if i drew a pic to explain.
As for sideseal failure, generally you'll have blowby into the oil/exhaust etc and only 1 face will be low with the other 2 being normal.
motomouse: did you go on a saturday? If so thats probably why, otherwise, it's probably because I was involved in something serious and they didnt want you to leave and comeback another time so they just said i wasn't there.
as for oil, in my rotarys i run 10w30 castrol gtx in winter (my cars dont ever see winter tho) and 20w50 in summer. thats in a 13bt and 13brew.
kevin.
04-03-2009, 12:18 AM
#34
as a note BTW, we comp. tested his motor not too long ago, front rotor was weaker then rear but still good. Things seem to have gone downhill somewhat fast at least on the front rotor, rear rotor hasnt budged nearly as much.
None of the signs of a sideseal failure.
The lean condition leads me towards apex seals and charge contamination causing excess air in the mixture in the combustion chamber, just enough air to be compensated for without being too lean.
Looking at the face numbers obviously one face is a lot worse then the other 2, altho theyre not too far behind.
I'll try to take the best pics i can inside the exhaust ports, i have a video snake i can slide thru the spark plug holes too so we can check carbon conditions but she's been decarbed at least once, maybe more, i was hoping for just a stuck seal but went old school after the comp test (ATF and a steam bath if you must know lol) and nothing improved.
kevin.
None of the signs of a sideseal failure.
The lean condition leads me towards apex seals and charge contamination causing excess air in the mixture in the combustion chamber, just enough air to be compensated for without being too lean.
Looking at the face numbers obviously one face is a lot worse then the other 2, altho theyre not too far behind.
I'll try to take the best pics i can inside the exhaust ports, i have a video snake i can slide thru the spark plug holes too so we can check carbon conditions but she's been decarbed at least once, maybe more, i was hoping for just a stuck seal but went old school after the comp test (ATF and a steam bath if you must know lol) and nothing improved.
kevin.
numbers were :
Front 7.1 , 7.3, 7.1
Rear 7.5 7.6 7.8
The very first *engine stall* happen around 2-3 months after I got my car. I was going thru Williamsburg bridge, was trying to switch gears, as soon as I press the clutch in ------ Beeeeeeeeeeeep ----- engine just died. I was like "wtf just happened?" It was the first time thats why I still remember
It might be just some faulty parts in the first place.
*I miss my car
*
04-03-2009, 12:34 AM
#37
my motor felt extremely strong.. and in "spirited comparison" runs against others it was never let me down.
probably not another 8 though..
yeah I still had car payments but the insurance company gave me a decent settlement so I paid it all off and I have money to spare.. I may get a toy.. *cough* FD *cough*
probably not another 8 though..
yeah I still had car payments but the insurance company gave me a decent settlement so I paid it all off and I have money to spare.. I may get a toy.. *cough* FD *cough*
04-03-2009, 03:53 AM
#39
a.k.a. WhITeRE8
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Its a 2005
There were no CEL
But from time to time my motor just stalled at red light or when I try to hot-start it (meaning a driving it for a while, turn it off at gas station or something, come back and start it, it starts but then it stalls right away),
and of course, I get rough idle all the time (dropping below 700rpm)
There were no CEL
But from time to time my motor just stalled at red light or when I try to hot-start it (meaning a driving it for a while, turn it off at gas station or something, come back and start it, it starts but then it stalls right away),
and of course, I get rough idle all the time (dropping below 700rpm)
Last edited by SiLVeRE8; 04-03-2009 at 03:55 AM.
04-03-2009, 04:47 AM
#40
04-03-2009, 07:16 AM
#41
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... the numbers seemed awefully low to me for an "8 out of 10"
04-03-2009, 09:09 AM
#42
You should be able to find out if its the original engine. but u need to have a "Good" dealership.
Could you please tell me where Mazda is currently drawing the line on bad compression? My front rotor pulled a 6.9 / 6.9/ 7.0 and my dealer (who I don't trust at all) said the Mazda tech support rated my engine as a "8 out of 10"
... the numbers seemed awefully low to me for an "8 out of 10"
... the numbers seemed awefully low to me for an "8 out of 10"
but in Service manual ---
Standard - 830 kPa (120 psi) @ 250 rpm
Minimum - 680 kPa (98.6 psi) @ 250 rpm (I think they updated this part to 650 kPa, not so sure)
Standard difference in chambers - Within 150 kPa (21.8 psi) ( I think they updated this part to something less, cuz 150 kPa apart from each other is pretty huge difference)
Standard difference in rotors (between front and rear - Within 100 kPa (14.5 psi)
Last edited by nycgps; 04-03-2009 at 09:16 AM.
04-03-2009, 10:29 AM
#44
Registered
motor had 8.5 all around on rear rotor, front rotor was 7.0, 6.4, 5.4
(IIRC i just pmed him the right #'s and already forgot them)
Basically he had come in a few times for stalling concerns and other things. We had already decarbed and all. No CEL's. Car was running lean (about 11-12% LFT, normal SFT) just not enough to set off a CEL. Couple other data points I noticed that wouldn't be useful for you guys lol but there were small signs. Noticed a quick short start when warm would throw it to 750rpm, stumble down to 500 sometimes stall, then catch itself and idle at 700. Test drove it and it felt off to me, not too bad but something was missing down low, to me it was more noticeable in the "i have to pass this guy real quick and get over" power range.
As for what actually failed internally, nothing broken it seems. Personally I doubt it had anything to do with oil, generally we see rear rotor failures because the rear rotor always runs hotter internally. I'm thinking simply abnormal excessive wear of combustion surface and apex seals, most likely not really traceable to a specific reason.
i'll see if i find anything when replacing it.
As for a "mark" on the motor....it has a serial number I can write it down and post it when i pull it out.
Also, yes your car will be down for a while due to timing and the trans. Basically authorization and shipment of the motor can't start until I can fully diag the trans which takes a lot of back and forth between me and mazda.
About the trans, forgot to PM you this question, have you ever replaced your clutch? your pedal is very soft and the clutch grabs when its like 1mm off the ground which is abnormal. If you havent replaced the clutch, are you sure the clutch line was bled properly when the braided line was installed? In all honesty a pedal like this could cause hard shifting, since you have no problem with the other gears it's not going to be the cause of your reverse problem but just wondering whats up with the clutch.
kevin.
(IIRC i just pmed him the right #'s and already forgot them)
Basically he had come in a few times for stalling concerns and other things. We had already decarbed and all. No CEL's. Car was running lean (about 11-12% LFT, normal SFT) just not enough to set off a CEL. Couple other data points I noticed that wouldn't be useful for you guys lol but there were small signs. Noticed a quick short start when warm would throw it to 750rpm, stumble down to 500 sometimes stall, then catch itself and idle at 700. Test drove it and it felt off to me, not too bad but something was missing down low, to me it was more noticeable in the "i have to pass this guy real quick and get over" power range.
As for what actually failed internally, nothing broken it seems. Personally I doubt it had anything to do with oil, generally we see rear rotor failures because the rear rotor always runs hotter internally. I'm thinking simply abnormal excessive wear of combustion surface and apex seals, most likely not really traceable to a specific reason.
i'll see if i find anything when replacing it.
As for a "mark" on the motor....it has a serial number I can write it down and post it when i pull it out.
Also, yes your car will be down for a while due to timing and the trans. Basically authorization and shipment of the motor can't start until I can fully diag the trans which takes a lot of back and forth between me and mazda.
About the trans, forgot to PM you this question, have you ever replaced your clutch? your pedal is very soft and the clutch grabs when its like 1mm off the ground which is abnormal. If you havent replaced the clutch, are you sure the clutch line was bled properly when the braided line was installed? In all honesty a pedal like this could cause hard shifting, since you have no problem with the other gears it's not going to be the cause of your reverse problem but just wondering whats up with the clutch.
kevin.
Thanks.
04-03-2009, 10:39 AM
#46
Life begins @ 30 psi
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Yep. it was last tested on Sept 05, 2008 (have the invoice in front of me, lol)
numbers were :
Front 7.1 , 7.3, 7.1
Rear 7.5 7.6 7.8
The very first *engine stall* happen around 2-3 months after I got my car. I was going thru Williamsburg bridge, was trying to switch gears, as soon as I press the clutch in ------ Beeeeeeeeeeeep ----- engine just died. I was like "wtf just happened?" It was the first time thats why I still remember
It might be just some faulty parts in the first place.
*I miss my car*
numbers were :
Front 7.1 , 7.3, 7.1
Rear 7.5 7.6 7.8
The very first *engine stall* happen around 2-3 months after I got my car. I was going thru Williamsburg bridge, was trying to switch gears, as soon as I press the clutch in ------ Beeeeeeeeeeeep ----- engine just died. I was like "wtf just happened?" It was the first time thats why I still remember
It might be just some faulty parts in the first place.
*I miss my car
*In any case, getting a new motor under warranty is not a bad thing. You will have a nice shiny new engine and hopefully a lot more miles of use out of it.
04-03-2009, 12:31 PM
#47
thx.
i will get a reman from VA, just like most other ppl.
I have no idea what happened. i just drive regulary
maybe faulty parts ?
Those compression numbers don't sound bad, if it was degrading that fast from September 2008 to now down to a 5.5 on the front rotor something is pretty seriously wrong. That doesn't sound like long term wear to me, although admittedly I'm no expert. I just got a compression test a couple of months ago and had 7.8 on pretty much all faces and my engine is running great so your numbers as of September sound fine? Very curious what happened...
In any case, getting a new motor under warranty is not a bad thing. You will have a nice shiny new engine and hopefully a lot more miles of use out of it.
In any case, getting a new motor under warranty is not a bad thing. You will have a nice shiny new engine and hopefully a lot more miles of use out of it.
I have no idea what happened. i just drive regulary
maybe faulty parts ?
04-03-2009, 12:48 PM
#48
Registered
Something has to be wrong with Mazda's diagnostic criteria if they couldn't confirm there was a serious engine problem until now. 10 mpg should be a pretty good clue. Maybe you were masking the problem a little bit with premix, but your mileage over the last few years just suck too much to ignore.
04-03-2009, 01:28 PM
#49
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You were definitely the maintenance ***** of rx8club, but sadly your engine is still gone. I don't think it has anything to do with you though. Good luck with the new one!
04-03-2009, 01:36 PM
#50
Power!!
Catastrophic failure would be like falling off a cliff, going downhill fast (span of months) was perhaps a bad choice of words. It's got lots of "wear out" signs in the story, especially how the problem started slow. Also IIRC he stated he originally had a stalling problem once in a blue moon when he first got the car so it could lead all the way back to a bad/barely faulty part used during assembly.
With the way combustion happens in the rotary and the direction of the flame front typically the front apex seal has the greatest effect on a "chamber's" compression. Aka each face has a leading and trailing apex (just like your plugs lead is bottom, trail is top) The "leading" apex seal is more important for compression of each face because the flame front begins, and is strongest, at the leading edge of the rotor face, as it expands upward it slows and loses force. Also the trailing edge of the rotor face is less involved in "spinning" the leading face however is where all the force of combustion is focused on as it spins the rotor to get to the next face.
So typically lets say that Rotor Face 1 one worn/bad apex seal on the leading tip and all other apex seals are fine. Rotor Face 1 will have low compression, the next face will be fine, the 3rd face will generally have a compression number in the middle of Face 1 and 2, since it's trailing apex seal (face 1's leading) is bad and losing what you could call waste compression/combustion (most force exerted on trailing side of rotor is weak so the rotor can spin the right direction with no force acting against it.
Probably best if i drew a pic to explain.
As for sideseal failure, generally you'll have blowby into the oil/exhaust etc and only 1 face will be low with the other 2 being normal.
motomouse: did you go on a saturday? If so thats probably why, otherwise, it's probably because I was involved in something serious and they didnt want you to leave and comeback another time so they just said i wasn't there.
as for oil, in my rotarys i run 10w30 castrol gtx in winter (my cars dont ever see winter tho) and 20w50 in summer. thats in a 13bt and 13brew.
kevin.
With the way combustion happens in the rotary and the direction of the flame front typically the front apex seal has the greatest effect on a "chamber's" compression. Aka each face has a leading and trailing apex (just like your plugs lead is bottom, trail is top) The "leading" apex seal is more important for compression of each face because the flame front begins, and is strongest, at the leading edge of the rotor face, as it expands upward it slows and loses force. Also the trailing edge of the rotor face is less involved in "spinning" the leading face however is where all the force of combustion is focused on as it spins the rotor to get to the next face.
So typically lets say that Rotor Face 1 one worn/bad apex seal on the leading tip and all other apex seals are fine. Rotor Face 1 will have low compression, the next face will be fine, the 3rd face will generally have a compression number in the middle of Face 1 and 2, since it's trailing apex seal (face 1's leading) is bad and losing what you could call waste compression/combustion (most force exerted on trailing side of rotor is weak so the rotor can spin the right direction with no force acting against it.
Probably best if i drew a pic to explain.
As for sideseal failure, generally you'll have blowby into the oil/exhaust etc and only 1 face will be low with the other 2 being normal.
motomouse: did you go on a saturday? If so thats probably why, otherwise, it's probably because I was involved in something serious and they didnt want you to leave and comeback another time so they just said i wasn't there.
as for oil, in my rotarys i run 10w30 castrol gtx in winter (my cars dont ever see winter tho) and 20w50 in summer. thats in a 13bt and 13brew.
kevin.
Also I am completely surprised that engine wear can happen so drastically over a short period of time with "nothing wrong."
I am now officially holding my breath to see what happens...
Last edited by shaunv74; 04-03-2009 at 01:38 PM.