Decarbing - Before and After Rotor Pics
01-14-2013, 10:05 AM
#76
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I believe he was referring to the Mazda TSB that has the tech do a decarb as part of troubleshooting the "sluggish" and "low power" reports... the final step of which is flagging the engine as requiring a replacement.
Last edited by RIWWP; 01-14-2013 at 10:08 AM.
01-14-2013, 10:07 AM
#78
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Very good point. I can't argue with that.
So it removes the housing from consideration of problems with carbon buildup. Leaving just the rotor and seals as the problem source.
The carbon rotor faces don't cause any sealing problems, though I could see a change in airflow volume and static compression. Carbon is ever so slightly reducing the interior volume of any one stroke, though it would take significant buildup to produce a measurable difference. So we can disregard this impact. The only other impact I could see from carbon buildup on the rotor is a change in combustion efficiency, if the carbon is changing how the fuel condenses on the surface of the rotor. I expect there is a change here, however I can make no guesses at if it would be an improvement or a detriment.
Leaving the seals. Carbon here will be much more of a problem, displacing the seals as it gets behind the seal to the spring, and/or changing the effective shape of the seal.
From what I have seen so far a simple half can of seafoam per rotor has very minimal impact on how much carbon is around the seals. Lots of water did quite a bit more in the correct direction, however it clearly didn't go far enough yet.
A 'simple' decarb will certainly have minimal impact. Is it possible to actually achieve the full result people expect? I don't know. But I'm going to keep trying until I either I find that result or I don't have any methods left to try.
You are correct in that all I've proven so far is that seafoam and/or water will indeed remove carbon to a degree. The benefits of that and proper ways to use that are still open for debate.
Might I eventually figure out a way to effectively decarb? Maybe, maybe not. But I'll report everything I try and the results, both good and bad. Will I destroy my engine in the process? Maybe. But my 8 is barely driven as it is, it's paid off, and it's only a reman
An interesting thought.
Any ideas on how to keep the water heated reasonably for the 30+ minutes needed? I have a couple methods that I could use to keep the water heated, but I am trying to avoid doing anything that others might not have access to, at least for starters. I also suspect that the water in the tubing will have cooled down to ambient quite quickly, probably before it gets to the LIM. And I would expect that it saturates in heat up to the point of boiling when it gets into the engine, before it flashes to steam. I suspect that it wouldn't change the end result. Perhaps if the water entered the engine AS steam? That might produce different results. Good or bad is obviously unknown.
Perhaps using exhaust heat to heat/boil the water in a small diameter tube, like running a length along the exhaust piping, held to it for heat transfer. Probably far more trouble than it's worth.
I'll tuck stuff like that away for now, since I don't expect most people would be willing to go that far.
So it removes the housing from consideration of problems with carbon buildup. Leaving just the rotor and seals as the problem source.
The carbon rotor faces don't cause any sealing problems, though I could see a change in airflow volume and static compression. Carbon is ever so slightly reducing the interior volume of any one stroke, though it would take significant buildup to produce a measurable difference. So we can disregard this impact. The only other impact I could see from carbon buildup on the rotor is a change in combustion efficiency, if the carbon is changing how the fuel condenses on the surface of the rotor. I expect there is a change here, however I can make no guesses at if it would be an improvement or a detriment.
Leaving the seals. Carbon here will be much more of a problem, displacing the seals as it gets behind the seal to the spring, and/or changing the effective shape of the seal.
From what I have seen so far a simple half can of seafoam per rotor has very minimal impact on how much carbon is around the seals. Lots of water did quite a bit more in the correct direction, however it clearly didn't go far enough yet.
A 'simple' decarb will certainly have minimal impact. Is it possible to actually achieve the full result people expect? I don't know. But I'm going to keep trying until I either I find that result or I don't have any methods left to try.
You are correct in that all I've proven so far is that seafoam and/or water will indeed remove carbon to a degree. The benefits of that and proper ways to use that are still open for debate.
Might I eventually figure out a way to effectively decarb? Maybe, maybe not. But I'll report everything I try and the results, both good and bad. Will I destroy my engine in the process? Maybe. But my 8 is barely driven as it is, it's paid off, and it's only a reman
An interesting thought.
Any ideas on how to keep the water heated reasonably for the 30+ minutes needed? I have a couple methods that I could use to keep the water heated, but I am trying to avoid doing anything that others might not have access to, at least for starters. I also suspect that the water in the tubing will have cooled down to ambient quite quickly, probably before it gets to the LIM. And I would expect that it saturates in heat up to the point of boiling when it gets into the engine, before it flashes to steam. I suspect that it wouldn't change the end result. Perhaps if the water entered the engine AS steam? That might produce different results. Good or bad is obviously unknown.
Perhaps using exhaust heat to heat/boil the water in a small diameter tube, like running a length along the exhaust piping, held to it for heat transfer. Probably far more trouble than it's worth.
I'll tuck stuff like that away for now, since I don't expect most people would be willing to go that far.
Find the Aroma Single-Burner Portable Electric Range for an everyday low price at Walmart.com
He's basically saying Mazda wouldn't create a TSB with no results to just **** away money on warranty claims that corporate Mazda eventually reimburses to each dealership when a warranty TSB is performed.
Valid point. I'm sure Mazda engineers didn't just develop a procedure with no extensive testing. Sure would be nice to get one of those guys to chime in/ talk to regarding the subject.
01-14-2013, 12:33 PM
#81
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Just sharing my experience here.
Bought the car new in 2005.
Start showing sign of stalling after highway cruise around 40k miles on the engine, 2009.
Did seafoam using the method found on the forum, DIY section.
Cure the stalling issue, felt noticeable difference.
Premix since then. (Didn't premix before this, using 5w20 non-synthetic from day-1 til now)
Did compression test last month. 1st rotor at high 80s, 2nd rotor at low 90s, 250rpm.
Currently 80k miles on first engine.
Bought the car new in 2005.
Start showing sign of stalling after highway cruise around 40k miles on the engine, 2009.
Did seafoam using the method found on the forum, DIY section.
Cure the stalling issue, felt noticeable difference.
Premix since then. (Didn't premix before this, using 5w20 non-synthetic from day-1 til now)
Did compression test last month. 1st rotor at high 80s, 2nd rotor at low 90s, 250rpm.
Currently 80k miles on first engine.
01-14-2013, 01:07 PM
#82
I still wonder about a method I posted about a couple of months ago... https://www.rx8club.com/tech-garage-...aclean-239710/
No idea if the concern regarding this is valid or not and I certainly didn't dare to risk trying it yet
No idea if the concern regarding this is valid or not and I certainly didn't dare to risk trying it yet
01-15-2013, 08:08 AM
#83
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Another test complete, distilled water using the same method as the windshield washer fluid on sunday.
The engine struggles to hold an idle, adding ~20% STFT and hovering around a 16-17AFR, so I went ahead and kept the RPM up between 3,000-3,500rpm (periodic drops to idle to keep the ECU from cutting out the throttle on it's own) and not only were the AFRs hovering around 14.5-15.0 here, there was pretty much no smoke/steam from the tailpipes. It certainly suggests that the smoke you see otherwise is from the extra fuel burn, whether that fuel is from the cleaner you are using or the gas tank. It took about half an hour or so to go through the gallon of water. No exhaust glow, though the heat did dry up the wet ground under the 8. If you try this with a cat on, expect to have a glowing exhaust like the 7 guys, so take periodic breaks to let everything cool down.
I should have pics of the results up around noon eastern...
The engine struggles to hold an idle, adding ~20% STFT and hovering around a 16-17AFR, so I went ahead and kept the RPM up between 3,000-3,500rpm (periodic drops to idle to keep the ECU from cutting out the throttle on it's own) and not only were the AFRs hovering around 14.5-15.0 here, there was pretty much no smoke/steam from the tailpipes. It certainly suggests that the smoke you see otherwise is from the extra fuel burn, whether that fuel is from the cleaner you are using or the gas tank. It took about half an hour or so to go through the gallon of water. No exhaust glow, though the heat did dry up the wet ground under the 8. If you try this with a cat on, expect to have a glowing exhaust like the 7 guys, so take periodic breaks to let everything cool down.
I should have pics of the results up around noon eastern...
01-15-2013, 10:29 AM
#85
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I'll have to try this. I seafoamed my 8 yesterday...wish I knew of RIWWP's findings before I went through the trouble of doing it...hell I even got pulled over for "excessive smoking"! Little/no steam=😃
01-15-2013, 11:03 AM
#87
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Compiling pictures from the latest. It does have more carbon removal, but it's only slowly making progress. I'd probably have to push FAR more water through the engine than I have time or patience for.
About the only thing I've thought of that might do it would be rotating the engine to have each seal at a plug hole and using the cold pressurized carb cleaner to strip the carbon off, rotate to the next, etc...
However, that is probably a stupid idea since you could easily end up with a carbon locked engine from the chunks that come off.
The water/meth injection probably only slowly cleans carbon that exists, but otherwise probably more prevents it from sticking the first place. Probably by keeping it suspended in the gaseous mix?
Pictures will be up in a bit, but pretty sure I'm done with testing methods for now.
About the only thing I've thought of that might do it would be rotating the engine to have each seal at a plug hole and using the cold pressurized carb cleaner to strip the carbon off, rotate to the next, etc...
However, that is probably a stupid idea since you could easily end up with a carbon locked engine from the chunks that come off.
The water/meth injection probably only slowly cleans carbon that exists, but otherwise probably more prevents it from sticking the first place. Probably by keeping it suspended in the gaseous mix?
Pictures will be up in a bit, but pretty sure I'm done with testing methods for now.
Last edited by RIWWP; 01-15-2013 at 11:07 AM.
01-15-2013, 12:08 PM
#88
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Here are the rotor pics from running 1 gallon of distilled water through both rotors at the same time, with RPMs held around 3,000-3,500 RPM throughout the ingestion. This ingestion method also had a 2nd T in the line to pull in air as well as water, which resulted in the water turning into droplets in the tube and reduced the amount of water the engine was seeing at once.
Front rotor and rear rotor, all faces.
Carbon was definitely removed from the patches near the seals vs the last set of pics, but it isn't very dramatic.
Should I repeat only without the 2nd T to reduce the volume? The engine struggles to stay alive even at 3,000rpm, as it's quite a bit more water.
In theory, I could also do this with the last 6oz of seafoam, but I don't expect that it will actually be much different in results.
It does raise the question though, using a soaking method WOULD get the seafoam into the carbon at the seals. Does the seal motion after this help break out carbon? I don't know.
I suppose I'm still too curious to give up yet, even though I am leaning that way
And again, if anyone want original groups or of these larger compilations (they are 31% of original size) PM me your email address. The zip file of everything I've taken pictures so far is 130mb, so that isn't really emailable.
Front rotor and rear rotor, all faces.
Carbon was definitely removed from the patches near the seals vs the last set of pics, but it isn't very dramatic.
Should I repeat only without the 2nd T to reduce the volume? The engine struggles to stay alive even at 3,000rpm, as it's quite a bit more water.
In theory, I could also do this with the last 6oz of seafoam, but I don't expect that it will actually be much different in results.
It does raise the question though, using a soaking method WOULD get the seafoam into the carbon at the seals. Does the seal motion after this help break out carbon? I don't know.
I suppose I'm still too curious to give up yet, even though I am leaning that way
And again, if anyone want original groups or of these larger compilations (they are 31% of original size) PM me your email address. The zip file of everything I've taken pictures so far is 130mb, so that isn't really emailable.
01-16-2013, 07:42 AM
#89
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01-16-2013, 07:44 AM
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I'll have more pics up in a bit. I did a traditional seafoam last night, letting seafoam soak in the engine for an hour. I don't expect it will have done much, if anything.
01-16-2013, 08:38 AM
#91
one thing i noticed on my engines ( water meth being used intermediately) is I have less carbon on the sides of the rotor--go figure?
Of course I did have less than normal carbon buildup on the rotor fronts too.
Now whether that was enough to help anything --I truely dont know. Couldnt hurt though?
Of course I did have less than normal carbon buildup on the rotor fronts too.
Now whether that was enough to help anything --I truely dont know. Couldnt hurt though?
01-16-2013, 09:09 AM
#92
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Generally I agree OD. Carbon removal is never bad for the engine. Whether or not the carbon removal is significant enough to make an impact, or whether or not it is being removed where it counts... those are the questions that will still be debated.
Just finished taking the pics. Seafoam soaking does as much as expected. Nothing.
Not even going to bother putting together the full compilation. Attached are 2 pics, one from before the soak (417), one from after (470). Both from the same point on the same rotor. Matching them up is easy at this point, since each rotor tip has formed it's own unique carbon removal pattern.
If anyone has any suggestions for something else to try that would be reasonable for everyone to have access to, go ahead with the suggestion. I'm otherwise done, and will be putting in the new plugs and doing the oil flush this weekend, and will send a sample out for testing for water/contamination.
Just finished taking the pics. Seafoam soaking does as much as expected. Nothing.
Not even going to bother putting together the full compilation. Attached are 2 pics, one from before the soak (417), one from after (470). Both from the same point on the same rotor. Matching them up is easy at this point, since each rotor tip has formed it's own unique carbon removal pattern.
If anyone has any suggestions for something else to try that would be reasonable for everyone to have access to, go ahead with the suggestion. I'm otherwise done, and will be putting in the new plugs and doing the oil flush this weekend, and will send a sample out for testing for water/contamination.
01-16-2013, 09:24 AM
#94
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As far as I am concerned there was never a debate as to whether the seafoam/zoom zoom cleaner was effective or not. It isn't..
Is that what you got from this thread, that ingesting water into your engine is effective? Effective at doing what? What do you think the overall results of this are and what are the benefits? I'm just curious what you think and why your conclusions would lead you to just run out and do this.
I would have loved to see tear down pics of your old engine, why didn't you post them up? I don't think water/meth can hurt, I just wonder if it's a huge waste of time, money, and effort. maybe I will run it on my next engine and then when that ones fails I will be able to tear it down and see if there are any obvious benefits.
Is that what you got from this thread, that ingesting water into your engine is effective? Effective at doing what? What do you think the overall results of this are and what are the benefits? I'm just curious what you think and why your conclusions would lead you to just run out and do this.
one thing i noticed on my engines ( water meth being used intermediately) is I have less carbon on the sides of the rotor--go figure?
Of course I did have less than normal carbon buildup on the rotor fronts too.
Now whether that was enough to help anything --I truely dont know. Couldnt hurt though?
Of course I did have less than normal carbon buildup on the rotor fronts too.
Now whether that was enough to help anything --I truely dont know. Couldnt hurt though?
01-16-2013, 09:29 AM
#95
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About the only further 'test' I could see being worth trying is a pre-post on a daily driven 8 at a track day.
I found these two threads from the same guy that used a $40,000 borescope to take pics inside his cylinders, before water/meth injection, and 2 gallons later:
Before: A peak inside my motor - Mazdaspeed Forums
After: -+- Progress of Methanol Injection in cleaning my motor -+- - Mazdaspeed Forums
I expect this will be largely ignored as being from a piston engine though.
I found these two threads from the same guy that used a $40,000 borescope to take pics inside his cylinders, before water/meth injection, and 2 gallons later:
Before: A peak inside my motor - Mazdaspeed Forums
After: -+- Progress of Methanol Injection in cleaning my motor -+- - Mazdaspeed Forums
I expect this will be largely ignored as being from a piston engine though.
01-16-2013, 09:37 AM
#96
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Pretty significant difference. I'm not sure how that would translate into a better running or longer lasting engine but the water/meth combo seems to work well. I wonder if it was boost juice or a homemade concoction and if he was running pump gas. I also wonder how often that engine was tracked and if there would have been a big difference from just tracking it anyway. Is that direct injection speed 3 engine or a Miata engine?
01-16-2013, 09:41 AM
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Speed3, 21,000 miles. Pulled these posts from his thread:
He daily drives it, so I would expect it's pump gas.
After this, i dont think it happens as quickly as we think. While it does a good job of preventing more deposits, it only very slowly cleans the ones that are already there. It takes me about a month to go through a gallon of water/meth mix, and i am running the do7 nozzle (relatively large)
I am using the devils own stage 2 progressive kit.
01-16-2013, 09:51 AM
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From this RX7 thread: Making The Case For The <Rotary> Powered FD: The Fix - RX7Club.com
It talks largely about the failure causes, why and all. But this was one thing that really caught my eye regarding decarbing and water/meth:
It's pretty conclusive for me and I have no reason to believe this might not be true.
It talks largely about the failure causes, why and all. But this was one thing that really caught my eye regarding decarbing and water/meth:
After 4 years of nothing but happy thrashing my curiosity finally won out so a week ago I yanked my perfectly running motor to see what was going on inside.
It looked and spec’d pretty much as it had when I built it four years ago. Zero carbon near any of the seal grooves. Side seal clearance, an under-appreciated but very important engine metric, had increased but one thousandth!
I was talking to my go-to guy about my motor and just for fun asked him to guess my side seal clearance. He knew my motor was in great shape and guessed 5 thousandths. My side seals were a tight 3 thousandths!
It looked and spec’d pretty much as it had when I built it four years ago. Zero carbon near any of the seal grooves. Side seal clearance, an under-appreciated but very important engine metric, had increased but one thousandth!
I was talking to my go-to guy about my motor and just for fun asked him to guess my side seal clearance. He knew my motor was in great shape and guessed 5 thousandths. My side seals were a tight 3 thousandths!
01-16-2013, 10:01 AM
#99
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IIRC, that Howard Coleman guy was found to be full of **** about some things so I would take his info with a grain of salt. I will read the thread though.
Last edited by 9krpmrx8; 01-16-2013 at 10:04 AM.
01-16-2013, 10:01 AM
#100
I don't see what the benefit of getting the carbon out is.....if you cant get the carbon from around and behind the seals there is no point.
also, not sure if I overlooked it, but getting the carbon off is the same concept of cleaning your hot skillet with water, it will remove carbon immediatly from the temp change
also, not sure if I overlooked it, but getting the carbon off is the same concept of cleaning your hot skillet with water, it will remove carbon immediatly from the temp change
