rx8 engine life
03-30-2007, 10:13 PM
#51
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Originally Posted by AdRoCK3217
I think the chemical you are thinking of is...carburetor cleaner, or WATER.
Letting either of these get vacuum into your engine will cause it to clean itself, like a steam cleaning.
The carburetor cleaner is not recommended, however, as it removes oil and leaves behind a residue which makes the oil unable to lubricate. Simply letting a gallon of water get sucked into your engine (not all at once) and holding the gas pedal down enough to keep the engine from stalling, will clean out almost all the carbon in your engine.
Of the engines I've seen post-tear down with this procedure done, ALL of them have been spit-shine clean on the inside. They looked brand new.
Letting either of these get vacuum into your engine will cause it to clean itself, like a steam cleaning.
The carburetor cleaner is not recommended, however, as it removes oil and leaves behind a residue which makes the oil unable to lubricate. Simply letting a gallon of water get sucked into your engine (not all at once) and holding the gas pedal down enough to keep the engine from stalling, will clean out almost all the carbon in your engine.
Of the engines I've seen post-tear down with this procedure done, ALL of them have been spit-shine clean on the inside. They looked brand new.
Brendan
03-30-2007, 10:17 PM
#52
Originally Posted by Brettus
You are confusing RPM & velocity .....
Yeah, that's why if you read the rest of my post I said you can't compare piston speed to rotor speed because rotors move rotational (like rpm) whereas a piston moves up and down.
I already said that......
03-30-2007, 10:17 PM
#53
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Originally Posted by Nemesis8
You got past the recall test with a bad engine?
Brendan
03-30-2007, 10:38 PM
#54
Originally Posted by chickenwafer
Yeah, that's why if you read the rest of my post I said you can't compare piston speed to rotor speed because rotors move rotational (like rpm) whereas a piston moves up and down.
I already said that......
I already said that......
03-31-2007, 09:50 AM
#55
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Originally Posted by chickenwafer
Gearing has nothing to due with rotor speed inside the engine. The rotors turn at 1/3 the speed of the eccentric shaft due to the rotors "stroke" (if comparing to a piston engine) or length or travel during a combustion cycle.
But reguarding e-shaft speed: In a convetional V8 engine, the pistons are only moving at 1/4 the crankshaft speed (where RPM readings from from), you but can't exactly compare piston rpm to rotary engine like apples to apples because rotars move in an orbital contunious movement (rotational), whereas pistons move up and down, stopping and starting 4 times during a complete power cycle, and their movement isn't rotational like a rotor is.
But reguarding e-shaft speed: In a convetional V8 engine, the pistons are only moving at 1/4 the crankshaft speed (where RPM readings from from), you but can't exactly compare piston rpm to rotary engine like apples to apples because rotars move in an orbital contunious movement (rotational), whereas pistons move up and down, stopping and starting 4 times during a complete power cycle, and their movement isn't rotational like a rotor is.
Wait, what? Stroke alone does not make the rotors spin at 1/3 the speed, that's just stupid. The stationary gears are there for a reason. A stationary gear is 1/3 the size of the rotor gear, before calling me out, tear down an engine or two..
04-02-2007, 12:42 PM
#57
the internal gears do aid in determining the orbit path of the rotor, yes. I was confused when you just said "gears" and nothing else and thought you were talking about the transmission, which has nothing to do with orbit of the rotors.
The orbit path is also determined by the shape of the lobes on the e-shaft and size of the off center hole in the rotor.
But maybe you should grow up before getting all worked about something on the internet
The orbit path is also determined by the shape of the lobes on the e-shaft and size of the off center hole in the rotor.
But maybe you should grow up before getting all worked about something on the internet
04-02-2007, 12:48 PM
#58
Originally Posted by Unnatural1
Lots of cars do and will. We don't do a compression test unless you're experiencing a power issue or your engine has flooded a couple of times since the recall was performed.
Brendan
Brendan
04-02-2007, 01:05 PM
#59
Screw gas mileage
Originally Posted by expo1
I guess I need to worry.
how's your clutch holding up? I keep seeing these horror stories about them only lasting 40-50k and I want a glimmer of hope
04-02-2007, 02:58 PM
#61
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Originally Posted by chickenwafer
But maybe you should grow up before getting all worked about something on the internet
I didn't get worked up, I just despise people who say I'm wrong when I'm not
07-03-2007, 09:41 PM
#63
Each time a rotor moves 1/3 of the way around its orbit, the eccentric shaft spins once. That is just the nature of the motor and epitrochoidal movement.
If the eccentric shaft and rotor moved at the same speed, you wouldn't need a bearing between them.
Or, did I miss something in the context of this argument?
I just did both of the above techniques to my motor.
I had done the ATF trick when I dropped it in back in May, which released a TON of black, gooey crap.
A scoping of the rotors at that time revealed that they were mostly smooth, as were the apex seal seats. The compression was in the 900 range across the board.
Recently, I re-ran my compression and found it had dropped into the 800 range. This is with only about a thousand or so miles since the last cleaning.
So, I did it again, this time with water.
That seemed to release *some* gunk, so I soaked it with ATF again before I went away for a week and blew it out again today.
A TON of crap shot out of the plug holes again.
Compression went back up to 900 across the board.
So, yes, carbon is a real enemy to this engine and it might not take very long to really crap the engine up.
Last edited by MazdaManiac; 07-03-2007 at 09:48 PM.
07-03-2007, 10:37 PM
#66
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For reference:
There's a 2004 RX8 on Cars.Com with 134,187 miles on it and bunches with over 70,000 miles. There's also an RX7 with 235,477 miles on it and 25 more with over 100,000 miles on them.
There's a 2004 RX8 on Cars.Com with 134,187 miles on it and bunches with over 70,000 miles. There's also an RX7 with 235,477 miles on it and 25 more with over 100,000 miles on them.
07-04-2007, 12:35 AM
#68
Because the rotors don't "spin", they orbit.
Each time a rotor moves 1/3 of the way around its orbit, the eccentric shaft spins once. That is just the nature of the motor and epitrochoidal movement.
If the eccentric shaft and rotor moved at the same speed, you wouldn't need a bearing between them.
Or, did I miss something in the context of this argument?
Sorry to cause a threadsurrection, but I thought this is relevant.
I just did both of the above techniques to my motor.
I had done the ATF trick when I dropped it in back in May, which released a TON of black, gooey crap.
A scoping of the rotors at that time revealed that they were mostly smooth, as were the apex seal seats. The compression was in the 900 range across the board.
Recently, I re-ran my compression and found it had dropped into the 800 range. This is with only about a thousand or so miles since the last cleaning.
So, I did it again, this time with water.
That seemed to release *some* gunk, so I soaked it with ATF again before I went away for a week and blew it out again today.
A TON of crap shot out of the plug holes again.
Compression went back up to 900 across the board.
So, yes, carbon is a real enemy to this engine and it might not take very long to really crap the engine up.
Each time a rotor moves 1/3 of the way around its orbit, the eccentric shaft spins once. That is just the nature of the motor and epitrochoidal movement.
If the eccentric shaft and rotor moved at the same speed, you wouldn't need a bearing between them.
Or, did I miss something in the context of this argument?
Sorry to cause a threadsurrection, but I thought this is relevant.
I just did both of the above techniques to my motor.
I had done the ATF trick when I dropped it in back in May, which released a TON of black, gooey crap.
A scoping of the rotors at that time revealed that they were mostly smooth, as were the apex seal seats. The compression was in the 900 range across the board.
Recently, I re-ran my compression and found it had dropped into the 800 range. This is with only about a thousand or so miles since the last cleaning.
So, I did it again, this time with water.
That seemed to release *some* gunk, so I soaked it with ATF again before I went away for a week and blew it out again today.
A TON of crap shot out of the plug holes again.
Compression went back up to 900 across the board.
So, yes, carbon is a real enemy to this engine and it might not take very long to really crap the engine up.
Mind to share your experience? if I want to do it, I should use the vacuum hole on the passenger side of the engine, right ? (if you have a picture to show that would be great)
07-04-2007, 12:49 AM
#69
Yes.
You hook up two vacuum lines to both ports on the intake manifold on the passenger side.
Run both hoses into a gallon jug of distilled water and pinch both hoses off with a vice grip or something similar.
Start the motor and warm it up.
Then, you have someone hold the engine to 3000 RPM and un-pinch the lines until water starts to enter the engine.
The assistant will have to give it more gas to keep it at 3000. If it starts stumbling too badly, pinch the lines again until it clears a little and then release them again.
It is almost impossible to "hydro-lock" a rotary and even if you did manage it, there are no rods to bend, so the motor will just stop.
If it does stall, let it sit for a minute with the water lines pinched.
Really, I felt the ATF cleaning did a better job.
Just pull the leading spark plugs and the ESS connector and force about 2oz of ATF through those same vacuum ports (both of them since each feeds a separate rotor).
Crank the motor just enough to spin it 1/2 rev and add another oz. Repeat until ATF is oozing out of the plug holes.
Replace the vacuum port plugs and let the motor sit over night.
In the morning, pull the trailing plugs also and clean all the plugs with brake cleaner.
Then, put some paper towels over the plug holes (lots of 'em) and crank the motor for about 30 seconds with the gas pedal down.
The crap that will come out of the plug holes will scare you.
Do that again and then re-install the plugs and reconnect the ESS.
Prepare for the biggest, nastiest cloud you have ever experienced and start the motor.
It might run rough, but let it run until it stops smoking.
Hold the RPMs up to 4k or so for a minute once it smooths out.
Pull the plugs and clean them again and then change your oil.
You hook up two vacuum lines to both ports on the intake manifold on the passenger side.
Run both hoses into a gallon jug of distilled water and pinch both hoses off with a vice grip or something similar.
Start the motor and warm it up.
Then, you have someone hold the engine to 3000 RPM and un-pinch the lines until water starts to enter the engine.
The assistant will have to give it more gas to keep it at 3000. If it starts stumbling too badly, pinch the lines again until it clears a little and then release them again.
It is almost impossible to "hydro-lock" a rotary and even if you did manage it, there are no rods to bend, so the motor will just stop.
If it does stall, let it sit for a minute with the water lines pinched.
Really, I felt the ATF cleaning did a better job.
Just pull the leading spark plugs and the ESS connector and force about 2oz of ATF through those same vacuum ports (both of them since each feeds a separate rotor).
Crank the motor just enough to spin it 1/2 rev and add another oz. Repeat until ATF is oozing out of the plug holes.
Replace the vacuum port plugs and let the motor sit over night.
In the morning, pull the trailing plugs also and clean all the plugs with brake cleaner.
Then, put some paper towels over the plug holes (lots of 'em) and crank the motor for about 30 seconds with the gas pedal down.
The crap that will come out of the plug holes will scare you.
Do that again and then re-install the plugs and reconnect the ESS.
Prepare for the biggest, nastiest cloud you have ever experienced and start the motor.
It might run rough, but let it run until it stops smoking.
Hold the RPMs up to 4k or so for a minute once it smooths out.
Pull the plugs and clean them again and then change your oil.
Last edited by MazdaManiac; 07-04-2007 at 12:31 PM.
07-04-2007, 12:31 PM
#72
Got Another Rotary
Yes.
Really, I felt the ATF cleaning did a better job.
Just pull the leading spark plugs and the ESS connector and force about 2oz of ATF through those same vacuum ports (both of them since each feeds a separate rotor).
Crank the motor just enough to spin it 1/2 rev and add another oz. Repeat until ATF is oozing out of the plug holes.
Replace the vacuum port plugs and let the motor sit over night.
In the morning, pull the trailing plugs also and clean all the plugs with brake cleaner.
Then, put some paper towels over the plug holes (lots of 'em) and crank the motor for about 30 seconds with the gas pedal down.
The crap that will come out of the plug holes will scare you.
Do that again and then re-install the plugs and reconnect the ESS.
Prepare for the biggest, nastiest cloud you have ever experienced and start the motor.
It might run rough, but let it run until it stops smoking.
Hold the RPMs up to 4k or so for a minute once it smooths out.
Pull the plugs and clean them again and then change your oil.
Really, I felt the ATF cleaning did a better job.
Just pull the leading spark plugs and the ESS connector and force about 2oz of ATF through those same vacuum ports (both of them since each feeds a separate rotor).
Crank the motor just enough to spin it 1/2 rev and add another oz. Repeat until ATF is oozing out of the plug holes.
Replace the vacuum port plugs and let the motor sit over night.
In the morning, pull the trailing plugs also and clean all the plugs with brake cleaner.
Then, put some paper towels over the plug holes (lots of 'em) and crank the motor for about 30 seconds with the gas pedal down.
The crap that will come out of the plug holes will scare you.
Do that again and then re-install the plugs and reconnect the ESS.
Prepare for the biggest, nastiest cloud you have ever experienced and start the motor.
It might run rough, but let it run until it stops smoking.
Hold the RPMs up to 4k or so for a minute once it smooths out.
Pull the plugs and clean them again and then change your oil.
Also, LC20 or FP make very good cleaners for feeding the engine through vacuum again because it emulsifies carbon instead of just chunking it off like water and some other oils/detergents can do.
Last edited by Jax_RX8; 07-04-2007 at 12:48 PM.
07-04-2007, 12:38 PM
#74
Got Another Rotary
This actually is somewhat of an urban legend - ATF really doesn't have any more detergents than your average oil. Not to say it won't clean, it will, but a dedicated, more concentrated cleaner like FP or LC will clean better.
