looks like a Motul can 
Oops. 25k miles on oil on Mazda RX-8.
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Weird, because Mazda has always recommended against using synthetic in the rotaries here in the US.
In Europe, synthetic is factory fill on the RX-8.
In Europe, synthetic is factory fill on the RX-8.
I have been hearing for years about not running synthetic oil in Mazda rotary engines. But I bought a new RX7 in 1980 and I ran nothing but Mobil 1 in it until I traded it with 120,000 miles on it. The day I traded it, it ran as good as the day I got it.
I don't know if they have redesigned the oiling system in the rotary engine since I had mine, but my carburetor engine injected oil with the gas mixture, so it was designed to use oil. The rotary engine is essentially a two-stroke engine as its power "stroke" happens every second revolution.
I don't know if they have redesigned the oiling system in the rotary engine since I had mine, but my carburetor engine injected oil with the gas mixture, so it was designed to use oil. The rotary engine is essentially a two-stroke engine as its power "stroke" happens every second revolution.
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Originally Posted By: CharlieJ
Notice that one of those bottles is marked "Pre-Mix". Some race rotary engines run a gas-oil mixture just like a two stroke.
When I ran Mobil 1 in my RX-7, Mobil advertised the 20,000 mile OCI. I didn't go that long, but because of the frequent top offs as it used oil, I would go 10-12,000 miles between changes. Worked for me.
Notice that one of those bottles is marked "Pre-Mix". Some race rotary engines run a gas-oil mixture just like a two stroke.
When I ran Mobil 1 in my RX-7, Mobil advertised the 20,000 mile OCI. I didn't go that long, but because of the frequent top offs as it used oil, I would go 10-12,000 miles between changes. Worked for me.
Synthetic in a rotary is fine. From what I remember mazda said that years ago not to put that in
I'd use syn in that engine but if you don't want to, use Pennzoil yellow bottle but do a UOA at 3K or so.
Originally Posted By: Spyder7
Originally Posted By: kbohip72
Originally Posted By: tinmanSC
Well, she's getting new oil every 4K miles. The RX-8 (i think) only has a 4qt sump capacity. So it's had 25 quarts of oil through it. The filter is another story. Based on that rate of oil consumption, I bet this engine fared pretty well, all things considered. Of course, the rapid oil consumption may be due to the fact that it didn't get changes. 1Qt/1K is a lot, even for a rotory. But that prolly saved her engine, kinda killing two STONES with one BIRD on this one.
She says "she thinks" it uses about 1qt every 1k miles. Keep in mind she doesn't pop the hood unless she sees the oil level gauge light come on. Notice I said oil level gauge, not pressure gauge. The RX-8's come with a oil level gauge on the dash as they know the car will burn more than a quart between oil changes.
I wouldn't touch it. She's completely neglecting and abusing the engine. One oil change isn't going to prolong its life very long, and she'll learn the hard way when the light comes on just before it blows. Expensive lesson, but the only way it seems she'll learn it. Maybe then she'll take better care of her next car.
-Spyder
Yes, all of this is true. She totally screwed up and neglected that poor engine. Oh well, that's life. She added a quart of oil every 1K miles, which based on her mileage that's about a quart a month. That's pretty good, considering. Now, this is what she SAYS. But if it's true, i bet that engine will have some damage, but be OK. It might not live out the service life that it would have if it been properly maintained, but I really don't think it's going to go BOOM tomorrow.
The abuse of this engine will kill it by itself. The treatment, if continued, will be fatal. Why not change the treatment and hope for the best? Like i said, you're already dealing with a engine that is going to die if you do nothing. It's going to burn oil for the rest of it's life. Tough. Why not try and extend its life by giving it some resemblance of maintenance?
IMHO, get this thing on a normal maintenance schedule, and see what happens. It's not his fault, he's not gonna be paying for the damage. The worst that can happen is the appearance that changing the oil ruined the engine. If your engine is so far gone that changing the oil makes it go boom, then it was already toast. You just hadn't figured it out yet. Feel free to say I'm wrong, which I know people will, but the car only has 61K miles on it. This engine has a chance at staying in service of it gets maintenance, it doesn't have a chance if it's left to die.
Sorry for the long post, My neighbor didn't change the oil in his van for 2 years and 22K miles. We started the cleaning process 2 weeks ago.
Originally Posted By: kbohip72
Originally Posted By: tinmanSC
Well, she's getting new oil every 4K miles. The RX-8 (i think) only has a 4qt sump capacity. So it's had 25 quarts of oil through it. The filter is another story. Based on that rate of oil consumption, I bet this engine fared pretty well, all things considered. Of course, the rapid oil consumption may be due to the fact that it didn't get changes. 1Qt/1K is a lot, even for a rotory. But that prolly saved her engine, kinda killing two STONES with one BIRD on this one.
She says "she thinks" it uses about 1qt every 1k miles. Keep in mind she doesn't pop the hood unless she sees the oil level gauge light come on. Notice I said oil level gauge, not pressure gauge. The RX-8's come with a oil level gauge on the dash as they know the car will burn more than a quart between oil changes.
I wouldn't touch it. She's completely neglecting and abusing the engine. One oil change isn't going to prolong its life very long, and she'll learn the hard way when the light comes on just before it blows. Expensive lesson, but the only way it seems she'll learn it. Maybe then she'll take better care of her next car.
-Spyder
Yes, all of this is true. She totally screwed up and neglected that poor engine. Oh well, that's life. She added a quart of oil every 1K miles, which based on her mileage that's about a quart a month. That's pretty good, considering. Now, this is what she SAYS. But if it's true, i bet that engine will have some damage, but be OK. It might not live out the service life that it would have if it been properly maintained, but I really don't think it's going to go BOOM tomorrow.
The abuse of this engine will kill it by itself. The treatment, if continued, will be fatal. Why not change the treatment and hope for the best? Like i said, you're already dealing with a engine that is going to die if you do nothing. It's going to burn oil for the rest of it's life. Tough. Why not try and extend its life by giving it some resemblance of maintenance?
IMHO, get this thing on a normal maintenance schedule, and see what happens. It's not his fault, he's not gonna be paying for the damage. The worst that can happen is the appearance that changing the oil ruined the engine. If your engine is so far gone that changing the oil makes it go boom, then it was already toast. You just hadn't figured it out yet. Feel free to say I'm wrong, which I know people will, but the car only has 61K miles on it. This engine has a chance at staying in service of it gets maintenance, it doesn't have a chance if it's left to die.
Sorry for the long post, My neighbor didn't change the oil in his van for 2 years and 22K miles. We started the cleaning process 2 weeks ago.
Originally Posted By: jhs914
Originally Posted By: CharlieJ
Notice that one of those bottles is marked "Pre-Mix". Some race rotary engines run a gas-oil mixture just like a two stroke.
When I ran Mobil 1 in my RX-7, Mobil advertised the 20,000 mile OCI. I didn't go that long, but because of the frequent top offs as it used oil, I would go 10-12,000 miles between changes. Worked for me.
The bottles are marked 10w-30, Premix, 20w-50. I have disconnected the factory Oil Metering Pump from my 12A engine. I have been running a 100:1 ratio of Amsoil Saber Professional Pre-mix 2-cycle oil for years. To me, burning motor oil was a stupid idea from the beginning. Mazda should have had a separate reservoir for 2-cycle oil that metered into the oil injectors. But, that would have meant more maintenance for people who know nothing about cars and would equal less sales. By the way, my 26 year old rotary does not burn any oil.
Originally Posted By: CharlieJ
Notice that one of those bottles is marked "Pre-Mix". Some race rotary engines run a gas-oil mixture just like a two stroke.
When I ran Mobil 1 in my RX-7, Mobil advertised the 20,000 mile OCI. I didn't go that long, but because of the frequent top offs as it used oil, I would go 10-12,000 miles between changes. Worked for me.
The bottles are marked 10w-30, Premix, 20w-50. I have disconnected the factory Oil Metering Pump from my 12A engine. I have been running a 100:1 ratio of Amsoil Saber Professional Pre-mix 2-cycle oil for years. To me, burning motor oil was a stupid idea from the beginning. Mazda should have had a separate reservoir for 2-cycle oil that metered into the oil injectors. But, that would have meant more maintenance for people who know nothing about cars and would equal less sales. By the way, my 26 year old rotary does not burn any oil.
Originally Posted By: kbohip72
She drives the car pretty hard too.
At least she does not baby it. Some of the worst engines (rotary) I've seen with carbon build up are from engines that were not driven like they were meant to.
She drives the car pretty hard too.
At least she does not baby it. Some of the worst engines (rotary) I've seen with carbon build up are from engines that were not driven like they were meant to.
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Originally Posted By: CharlieJ
The bottles are marked 10w-30, Premix, 20w-50. I have disconnected the factory Oil Metering Pump from my 12A engine. I have been running a 100:1 ratio of Amsoil Saber Professional Pre-mix 2-cycle oil for years. To me, burning motor oil was a stupid idea from the beginning. Mazda should have had a separate reservoir for 2-cycle oil that metered into the oil injectors. But, that would have meant more maintenance for people who know nothing about cars and would equal less sales. By the way, my 26 year old rotary does not burn any oil.
I have heard of other people disconnecting the oil metering pump from the crankcase and running a separate reservoir for the oil injectors. They say it works well and allows the usage of synthetics. Never had a rotary so I've never tried it.
On a side note, I have heard that if you need to shut a rotary back off after a cold start, you can run it for 15 seconds at 3000 RPM and then shut it down without subsequent flooding.
Also, if you do flood the engine, I have read that you can remove the spark plugs and drop some oil into the engine manually and that will help it build compression and start.
The bottles are marked 10w-30, Premix, 20w-50. I have disconnected the factory Oil Metering Pump from my 12A engine. I have been running a 100:1 ratio of Amsoil Saber Professional Pre-mix 2-cycle oil for years. To me, burning motor oil was a stupid idea from the beginning. Mazda should have had a separate reservoir for 2-cycle oil that metered into the oil injectors. But, that would have meant more maintenance for people who know nothing about cars and would equal less sales. By the way, my 26 year old rotary does not burn any oil.
I have heard of other people disconnecting the oil metering pump from the crankcase and running a separate reservoir for the oil injectors. They say it works well and allows the usage of synthetics. Never had a rotary so I've never tried it.
On a side note, I have heard that if you need to shut a rotary back off after a cold start, you can run it for 15 seconds at 3000 RPM and then shut it down without subsequent flooding.
Also, if you do flood the engine, I have read that you can remove the spark plugs and drop some oil into the engine manually and that will help it build compression and start.
Originally Posted By: Brons2
I have heard of other people disconnecting the oil metering pump from the crankcase and running a separate reservoir for the oil injectors. They say it works well and allows the usage of synthetics. Never had a rotary so I've never tried it.
On a side note, I have heard that if you need to shut a rotary back off after a cold start, you can run it for 15 seconds at 3000 RPM and then shut it down without subsequent flooding.
Also, if you do flood the engine, I have read that you can remove the spark plugs and drop some oil into the engine manually and that will help it build compression and start.
Yeah, I have heard about that people running a separate reservoir as well. I have only flooded my Rx-7 once and it was when I was trying to start it while it had been in storage for many months. I put in an extra set of spark plugs (gotta have that when owning a rotary) and it fired right up.
I have heard of other people disconnecting the oil metering pump from the crankcase and running a separate reservoir for the oil injectors. They say it works well and allows the usage of synthetics. Never had a rotary so I've never tried it.
On a side note, I have heard that if you need to shut a rotary back off after a cold start, you can run it for 15 seconds at 3000 RPM and then shut it down without subsequent flooding.
Also, if you do flood the engine, I have read that you can remove the spark plugs and drop some oil into the engine manually and that will help it build compression and start.
Yeah, I have heard about that people running a separate reservoir as well. I have only flooded my Rx-7 once and it was when I was trying to start it while it had been in storage for many months. I put in an extra set of spark plugs (gotta have that when owning a rotary) and it fired right up.
She is your sister so of course you should help her. What is the factory OCI on that car?
Originally Posted By: tinmanSC
Originally Posted By: Spyder7
Originally Posted By: kbohip72
Originally Posted By: tinmanSC
Well, she's getting new oil every 4K miles. The RX-8 (i think) only has a 4qt sump capacity. So it's had 25 quarts of oil through it. The filter is another story. Based on that rate of oil consumption, I bet this engine fared pretty well, all things considered. Of course, the rapid oil consumption may be due to the fact that it didn't get changes. 1Qt/1K is a lot, even for a rotory. But that prolly saved her engine, kinda killing two STONES with one BIRD on this one.
She says "she thinks" it uses about 1qt every 1k miles. Keep in mind she doesn't pop the hood unless she sees the oil level gauge light come on. Notice I said oil level gauge, not pressure gauge. The RX-8's come with a oil level gauge on the dash as they know the car will burn more than a quart between oil changes.
I wouldn't touch it. She's completely neglecting and abusing the engine. One oil change isn't going to prolong its life very long, and she'll learn the hard way when the light comes on just before it blows. Expensive lesson, but the only way it seems she'll learn it. Maybe then she'll take better care of her next car.
-Spyder
Yes, all of this is true. She totally screwed up and neglected that poor engine. Oh well, that's life. She added a quart of oil every 1K miles, which based on her mileage that's about a quart a month. That's pretty good, considering. Now, this is what she SAYS. But if it's true, i bet that engine will have some damage, but be OK. It might not live out the service life that it would have if it been properly maintained, but I really don't think it's going to go BOOM tomorrow.
The abuse of this engine will kill it by itself. The treatment, if continued, will be fatal. Why not change the treatment and hope for the best? Like i said, you're already dealing with a engine that is going to die if you do nothing. It's going to burn oil for the rest of it's life. Tough. Why not try and extend its life by giving it some resemblance of maintenance?
IMHO, get this thing on a normal maintenance schedule, and see what happens. It's not his fault, he's not gonna be paying for the damage. The worst that can happen is the appearance that changing the oil ruined the engine. If your engine is so far gone that changing the oil makes it go boom, then it was already toast. You just hadn't figured it out yet. Feel free to say I'm wrong, which I know people will, but the car only has 61K miles on it. This engine has a chance at staying in service of it gets maintenance, it doesn't have a chance if it's left to die.
Sorry for the long post, My neighbor didn't change the oil in his van for 2 years and 22K miles. We started the cleaning process 2 weeks ago.
Absolutely. The seller I bought my car off took better care of it than the average car owner, but being a burner with a clogged PCV valve, it was also sludged, so her maintenance schedule wasn't quite ideak. Was the engine damaged when I bought it at 96k km and took over the maintenance on it - possibly, but based on how its been running over the 10k km I've put on it since, it doesn't seem likely.
I have the sludge process in reversal, and some ideas about reducing the consumption. But once the engine's cleaned out, whether I succeed at reducing consumption or not, I expect this engine to provide many years of trouble free service. Part of the regular maintenance for me is checking the oil level frequently and carrying a quart in the trunk. If its down a quarter quart, I add that to bring it back up to full. I don't put off checking or adding oil when its below the full line, and this is why I expect it to last.
Consumption in and of itself is not harmful. Its only a problem when the owner doesn't stay on top of it and waits for the oil light to come on before realizing its time to top up. If she were to begin checking it frequently (at least every fillup) and add however much it needs to bring it up to full, do a reasonable OC now and then, and at least change the filter when it should be changed, this RX-8 could likewise live several more years. But for that to happen, the neglect has to stop and she has to start following the regimen an oil burner like this requires.
-Spyder
Originally Posted By: Spyder7
Originally Posted By: kbohip72
Originally Posted By: tinmanSC
Well, she's getting new oil every 4K miles. The RX-8 (i think) only has a 4qt sump capacity. So it's had 25 quarts of oil through it. The filter is another story. Based on that rate of oil consumption, I bet this engine fared pretty well, all things considered. Of course, the rapid oil consumption may be due to the fact that it didn't get changes. 1Qt/1K is a lot, even for a rotory. But that prolly saved her engine, kinda killing two STONES with one BIRD on this one.
She says "she thinks" it uses about 1qt every 1k miles. Keep in mind she doesn't pop the hood unless she sees the oil level gauge light come on. Notice I said oil level gauge, not pressure gauge. The RX-8's come with a oil level gauge on the dash as they know the car will burn more than a quart between oil changes.
I wouldn't touch it. She's completely neglecting and abusing the engine. One oil change isn't going to prolong its life very long, and she'll learn the hard way when the light comes on just before it blows. Expensive lesson, but the only way it seems she'll learn it. Maybe then she'll take better care of her next car.
-Spyder
Yes, all of this is true. She totally screwed up and neglected that poor engine. Oh well, that's life. She added a quart of oil every 1K miles, which based on her mileage that's about a quart a month. That's pretty good, considering. Now, this is what she SAYS. But if it's true, i bet that engine will have some damage, but be OK. It might not live out the service life that it would have if it been properly maintained, but I really don't think it's going to go BOOM tomorrow.
The abuse of this engine will kill it by itself. The treatment, if continued, will be fatal. Why not change the treatment and hope for the best? Like i said, you're already dealing with a engine that is going to die if you do nothing. It's going to burn oil for the rest of it's life. Tough. Why not try and extend its life by giving it some resemblance of maintenance?
IMHO, get this thing on a normal maintenance schedule, and see what happens. It's not his fault, he's not gonna be paying for the damage. The worst that can happen is the appearance that changing the oil ruined the engine. If your engine is so far gone that changing the oil makes it go boom, then it was already toast. You just hadn't figured it out yet. Feel free to say I'm wrong, which I know people will, but the car only has 61K miles on it. This engine has a chance at staying in service of it gets maintenance, it doesn't have a chance if it's left to die.
Sorry for the long post, My neighbor didn't change the oil in his van for 2 years and 22K miles. We started the cleaning process 2 weeks ago.
Absolutely. The seller I bought my car off took better care of it than the average car owner, but being a burner with a clogged PCV valve, it was also sludged, so her maintenance schedule wasn't quite ideak. Was the engine damaged when I bought it at 96k km and took over the maintenance on it - possibly, but based on how its been running over the 10k km I've put on it since, it doesn't seem likely.
I have the sludge process in reversal, and some ideas about reducing the consumption. But once the engine's cleaned out, whether I succeed at reducing consumption or not, I expect this engine to provide many years of trouble free service. Part of the regular maintenance for me is checking the oil level frequently and carrying a quart in the trunk. If its down a quarter quart, I add that to bring it back up to full. I don't put off checking or adding oil when its below the full line, and this is why I expect it to last.
Consumption in and of itself is not harmful. Its only a problem when the owner doesn't stay on top of it and waits for the oil light to come on before realizing its time to top up. If she were to begin checking it frequently (at least every fillup) and add however much it needs to bring it up to full, do a reasonable OC now and then, and at least change the filter when it should be changed, this RX-8 could likewise live several more years. But for that to happen, the neglect has to stop and she has to start following the regimen an oil burner like this requires.
-Spyder
Like other said, the continuous top off of oil may have been the best thing happening to this engine.
The only thing I will do is to change the oil filter... for a good one in case it is forgot again (M1 or Amsoil).
She is your sister, so act as her brother and take care of her car (from what I understand, she doesn't live far).
Teach her the minimum maintenance she needs to do (you cannot be there everyday to start the car for her), and take care of the weekly or monthly maintenance.
Is 5W20 oil not too thin for this car? Maybe by moving it to a thicker oil, it will use less oil (and yes, I feel strange saying that). From what I see on the bottles shown here, it seems that xW30 oil should be used. Since it uses oil, I will stay with dino, whatever is on sale.
At least, as CharlieJ said, she is driving it correctly, that is good to hear (compliments are good before teaching something to someone, that is called positive reinforcement).
The only thing I will do is to change the oil filter... for a good one in case it is forgot again (M1 or Amsoil).
She is your sister, so act as her brother and take care of her car (from what I understand, she doesn't live far).
Teach her the minimum maintenance she needs to do (you cannot be there everyday to start the car for her), and take care of the weekly or monthly maintenance.
Is 5W20 oil not too thin for this car? Maybe by moving it to a thicker oil, it will use less oil (and yes, I feel strange saying that). From what I see on the bottles shown here, it seems that xW30 oil should be used. Since it uses oil, I will stay with dino, whatever is on sale.
At least, as CharlieJ said, she is driving it correctly, that is good to hear (compliments are good before teaching something to someone, that is called positive reinforcement).
Best way to keep consumption in check is to monitor it predictively, using the tripometer. Reset it after top-off and re-check at 500 miles. Adding in 1/2q increments is ideal, so find a number of miles that corresponds with that and use it as a milestone....she hits 600 miles, top it and reset the counter.
Yeah it's weird Mazda recommends a 30 weight across seas but the US models got the 20 weight spec?
Lots of talk about apex seal failures in the US models...
My close friend owns an '05, has been running a dino 5w-30, so far 70K on the clock. All seems good, still burns about a quart per 1K. I believe this was incorporated into the design to lube the apex seals?
Lots of talk about apex seal failures in the US models...
My close friend owns an '05, has been running a dino 5w-30, so far 70K on the clock. All seems good, still burns about a quart per 1K. I believe this was incorporated into the design to lube the apex seals?
Originally Posted By: Audi Junkie
Best way to keep consumption in check is to monitor it predictively, using the tripometer. Reset it after top-off and re-check at 500 miles. Adding in 1/2q increments is ideal, so find a number of miles that corresponds with that and use it as a milestone....she hits 600 miles, top it and reset the counter.
Or do what they did back in the days before trip meters: spend the extra minute when filling the gas tank to pop the hood, and look over the fluids while you check the oil. Its an easy habit to adopt, and one still recommended in every car manual I've seen, including my own. I do this every fillup. Sometimes a little more frequently, but that is the minimum and an easy and good habit to get into.
It also takes the guess work out of interpreting fluid levels, since I know when I last checked them and that they were all at the full line then, I know the interval that's occurred since any change. This is the simplest, fastest, and potentially most cost effective maintenance you can do.
-Spyder
Best way to keep consumption in check is to monitor it predictively, using the tripometer. Reset it after top-off and re-check at 500 miles. Adding in 1/2q increments is ideal, so find a number of miles that corresponds with that and use it as a milestone....she hits 600 miles, top it and reset the counter.
Or do what they did back in the days before trip meters: spend the extra minute when filling the gas tank to pop the hood, and look over the fluids while you check the oil. Its an easy habit to adopt, and one still recommended in every car manual I've seen, including my own. I do this every fillup. Sometimes a little more frequently, but that is the minimum and an easy and good habit to get into.
It also takes the guess work out of interpreting fluid levels, since I know when I last checked them and that they were all at the full line then, I know the interval that's occurred since any change. This is the simplest, fastest, and potentially most cost effective maintenance you can do.
-Spyder
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