I could write a big long thing about what it is, what it does and why we do it ... for now tho we use seafoam as opposed to the old school Automatic Trans Fluid because Mazda recommend zoom-zoom cleaner which is essentially sea-foam but more expensive
ATF is bad really and should be avoided!
Anyway rather than bashing away at my key board for the next hour for 'those in the know' to discredit what I write I think I`ll just use extracts from some whose opinion 'those in the know' actually appreciate
So here goes lets start with arron cake ey?
mmmm Mazdaspeed.com 1st gen forumArron Cake wrote:If you have been involved in the RX-7 community, you have probably heard mention of the "ATF trick", or "ATF treatment". It is often prescribed for serious flooding situations, and sometimes as a general maintenance item. Especially on a certain forum. However, misunderstandings about the use of automatic transmission fluid, or ATF, in rotary engines has caused damage to quite a number of cars. I am hoping that this page will provide a little info on the "ATF trick" that is rarely heard.
Basically, the ATF trick consists of introducing automatic transmission fluid into the working (combustion) chamber of a rotary engine. This is usually done by removing the leading spark plugs, and using a funnel and tube to pour a few ounces of fluid into the engine. The engine is then either rotated by hand or cranked over with the starter to distribute the fluid inside the engine. Common practice is to then leave the car overnight to allow the fluid to "do it's magic". The idea is that ATF dissolves any carbon deposits and cleans out the internal mechanism of the engine. ATF is also used in a situation of severe flooding. It is again poured into the engine through the spark plug holes. The ATF absorbs the extra fuel, and allows the apex seals form a better better seal and build up compression. The engine then starts and burns off the ATF.
The problem is, quite a number of people use the ATF trick as a general cure-all. What they don't realize is that ATF is in fact bad for the engine. ATF is a fairly corrosive liquid, designed for the environment in an automatic transmission. The seals and materials in an automatic transmission are different than those in the working chamber of your engine. While ATF may not be corrosive to the bands, clutches and gaskets in an automatic transmission, it is corrosive to carbon (which is good, and why it cleans the engine) and has been shown to affect the rubber O-rings used to seal the rotor housings together, as well as the o-rings used on the oil seals. ATF attacks all those seals, and if they were marginal to begin with, they will most certainly be ruined by the ATF trick. This is why there are so many complaints that sound like "I did the ATF trick a week ago and now my car smokes and burns oil". The ATF has damaged the seals, allowing oil to leak into the working chamber and be burned off. This is bad, and can only be cured by replacement of the seals, which of course requires disassembly of the engine. Since the ATF trick is most often used on marginal engines to try to increase the performance, problems are fairly common. So using ATF as a general "cure all" or engine cleanout method is not a good thing.
Another use is to try and free an engine that has become "carbon locked". Carbon locking occurs when a chunk of carbon dislodges from the rotor housing and jams the apex of the rotor against the housing. This prevents the engine from turning. ATF is poured into the engine in an attempt to dissolve the carbon. This procedure is entirely acceptable, as a carbon locked engine is usually on it's last legs anyway, and there's not a lot that can be done to make it run any worse. Because of the damage caused by carbon locking, the engine usually blows shortly after the carbon has been cleared.
Excessive use of ATF also has other side effects. For one, the spark plugs are fouled much more quickly. This is due to the deposits that build up as the ATF burns. It may not be a big deal, but fouled spark plugs need to be replaced otherwise they will cause loss of power and gas mileage. The same deposits that clog spark plugs are also blown into your exhaust. If you are running catalytic converters, the soot and forign matter may begin to clog up the honeycomb inside. If the converters were already marginal to begin with, the ATF treatment may be the "last straw". Of course, the engine oil should always be changed after using ATF since it will be contaminated. A slightly more amusing side effect are the intense clouds of strange-smelling white smoke. Be aware that the ATF trick will produce enough smoke to fill a neighbourhood quite effectively. This has resulted in concerned neighbours calling the fire department, police, etc.
The original use for ATF was to clear flooding. It is entirely acceptable in a situation of severe flooding to use ATF to restore engine compression and allow the engine to be started. ATF does not usually sit in a flooded engine long enough to cause damage to the seals, as shortly after the ATF is poured into the engine it is burned off on startup. However, oil works just as well and is much more benign.
There you have it, when you can and when you cannot use ATF. I hope that this saves at least a few cars out there.
Note: I have received alot of flack for this page. Many people were confused by my previous use of the term "side seals". What I really meant was "oil seals" or "oil o-rings". My mind always reverses them whenever I talk about the engine internals. This serves to confuse alot of people, and make me look like an idiot. I have corrected the terms above to make things more accurate. Obviously, ATF cannot attack the side seals in the engine because they are metal. The "ATF debate" is also not new. It has been going as long as there have been rotary engines, and won't stop anytime soon. Some have said ATF is the best thing since sliced bread, others have had their engine seriously damaged. This page is based on my experiences with ATF, and the fact that I personally know owners who have ruined their engines with this "fix all". For what it's worth.
Ash8 - australia - rx8clubBobrx7 wrote: One of the more common reasons for failure of rotary engines is actually very preventable and in many cases reversible. This entry will cover just how it�s done and why it works 95% of the time.
Rotor Seal Design
The rotary engine is among the simplest in overall design. No valves, cams, heads or any of the parts commonly associated with piston engines. This makes them extremely reliable with one major exception. . . the apex seals.
To seal the three tips of each rotor, a groove is machined to accept a long thin cast iron (in stock engines) insert. This is the apex seal. A spring, located behind the seal, applies the force needed to hold the seal in contact with the rotor housing wall as it passes around the inside housing wall. As the apex seals pass the narrow points in the housing, they are compressed against the springs and then move back outward in the wider parts of the housing. A corner seal at each end of the apex seal is also spring loaded to prevent combustion gasses from leaking around the ends of the rotor tip. Additional seals on the sides of the rotor complete the set to form a relatively leak-free chamber.
Over time, carbon, ash and oil sludge deposits will accumulate in the machined groove in the rotor tip. If allowed to remain, the apex seals will eventually begin to bind in the grooves and will not move outward completely during the combustion cycle or intake cycle. This allows gasses to escape into the next chamber, reducing compression. In the extreme, the apex seals will stick in the compressed position to the extent that virtually all compression is lost. At this point, the engine will likely refuse to run at all.
Dirty oil and general lack of maintenance is the most common cause of compression loss. The oil injection system on the rotary is designed to feed oil in to the chamber to keep both the housing walls and the apex and corner seals lubricated and clean. Dirty oil will simply throw grit, sludge and other combustion debris back into the chamber. Result, thousands of perfectly good 12A and 13B engines, or complete cars, rotting in the junk yard, for no good reason!!!!
Preventive Care
The obvious solution here is consistent oil changes. Never more than 3000 miles between changes and good (spelled Castrol GTX 20W50) oil with a new filter. By the way, the puny little factory filter is COMPLETELY inadequate. A remote filter setup that will allow the use of a 1 qt. filter is much better. At the very least, use a K&N or WIX filter in the stock location. These will filter particles down to 10 microns. A better oil cooler on those 83-85 12A engines is also an excellent idea.
The Fix
So what if your engine is already suffering from the dreaded sticking/seized apex seals, you ask?? Never fear. An old mechanics trick used to free up sticking valves and lifters works WONDERS on your rotary. The procedure works a little differently for carbureted engines that the EGI models, but accomplishes the same results.
1.
Disable the ignition primary circuit by disconnecting the igniters or the negative lead on each ignition coil.
2.
Remove the air cleaner lid on carbureted engines, or pull the Leading (lower) plugs on 13B EGI engines.
3.
For carbureted engines, pour 2 oz. Automatic Transmission Fluid (ATF) (the cheap stuff is fine) down each primary bore (the small ones) of the carb, while an assistant cranks the engine for 5 seconds or so. On EGI engines, use an oil squirt can and pump two or three shots into leach leading spark plug hole. Have an assistant lightly bump the starter two or three times, squirt in more oil, bump the starter, squirt, bump, squirt, bump. . . you get the idea. You want to get ATF in all chambers and thoroughly distributed. Reinstall the spark plugs on EGI engines.
4.
Allow the engine to sit in the ATF stew for AT LEAST 24 hours. Don�t be tempted to rush the process. This takes time. The detergents in the fluid, used to keep the small polished valves in an auto trans valve body free, will soften the carbon and sludge deposits.
5.
PLEASE. . . Make sure the car is outside for this step. You'll see why. Reconnect the ignition system, hold the throttle open � way on carbureted engine and start it up. Allow to idle. The neighbors will now think that Mt. St. Helens has erupted in you driveway or a massive brush fire has broken out. It will take about 5 minutes for the smoke to clear completely, since some of the ATF has worked it�s way into the exhaust pipe and must be burned off.
6.
Install a new set of plugs. The ATF will foul the old ones and may cause hi-speed misfire. Take the car out on the e-way and THRASH IT for a few miles to completely clear the chambers. 6 to 10 redline runs will do it.
At this point, the apex and corner seals can move freely again. In extreme cases, you may want to repeat the treatment after a week or so of driving. If so, hang on to the old plugs to use again for the second treatment.
If you were to perform a before and after compression test, you could potentially see an increase of 20 psi or more and will feel a whole lot of power that wasn�t there before. I have revived engines that would not start and know of a couple ITA drivers running junk yard engines brought back to life this way.
IT�S CHEAP. . . IT WORKS. . . And you can end up with a nearly new engine for $2. You�ve gotta love it!!
HAPPY ROTORING!!
Bobrx7
Ash8 wrote:IN the 1970's and 80's our Mazda Service Manger would personally fix Bad Compressions in 10A, 12A and 13B Rotaries with Upper Cylinder Lubrication and or mostly ATF (Automatic Transmission Fluid).
After performing a Mazda Compression Test most of the time he would diagnose sticking or stuck IN Rotor Tips APEX SEALS resulting in extreme Blow back and Poor Compressions, some symptoms would be NO Firing of Engines at all.
After the ATF method and a good on road Test Drive / THRASHING many of these engines were given a new life.
I found the same treatment on the web 30 years later.
While the SEAFOAM procedure is good for removing Carbon perhaps you could try the ATF one first and then follow it up with Seafoam.
Note: for those that have a billion years experience with rotarys but never heard of this procedure perhaps you ought to pull you head outta your arse and open your bloody eyes if you need more persuading just say I could list quotes allllllll day and even Mazda service bulletins if you like
For everyone else, I hope this has cleared things up a bit. theres plenty of info above ^^^^
Don`t go getting to excited tho, seafoaming should be left as a second to last resort its not a service doing it often would do more harm than good!