Atkins Rotary


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them here but we do try to answer the most common ones. Please give as much
details as possible when writing. Thank-You for visiting our site.

Having trouble installing you're oil control rings with our viton inserts?
Click here to see an instructional installation video.

    Should I replace my bearings at 100,000 miles?
    It depends on the wear, if they are copper in color then yes you would need to replace them. New bearings are a cheap way to ensure a longer lasting engine.
    My rx7 over pressurizes and/or bubbles into the overflow, how can I fix this?
    When ever the cooling system gets over pressurized the combustion chamber is leaking into the cooling system. This has happened either by overheating and melting a water jacket seal or by electrolysis which is caused from the antifreeze turning into an acid and eating away at the rotor housings. The only fix is rebuilding the engine, driving the car in this condition will not cause further damage but its not going to get any better and will most likely be emmiting white smoke. We have rebuilt engines in stock or you could rebuild the engine yourself using our dvd and one of our rebuild kits.
    After my car has warmed up the RPMs keep bouncing up and down, what is wrong?
    You probably need a new BAC valve which is located on the upper dynamic chamber on you're intake manifold. You might also need a new Throttle Position Sensor.
    Do you know how much it costs to install an engine?
    We no longer do installations, but I can refer you to a couple of local places. We also have a nation wide network that we can help you out with, give us a call at 360-832-1990.
    I think I have a carbon locked engine, what should I do?
    The throttle body is located on top of the engine and there are 3 or 4 nut caps that hold on a black hose that runs from the air cleaner box. When you remove the green fuse (86-88) from the fuse block by the front drivers side strut tower, it disables the ignition system and the fuel injection system so no more fuel is introduced into the engine. Remove the spark plugs, disable the ignition, and while spraying the power foam into the engine have some one crank on the engine so the foam will get into all of the chambers. Do not remove the top plugs unless you are unable to get the engine to turn over. The reverse engine treatment does not remove the carbon as well as the power foam and is a procedure that is done by the Mazda Dealers.

Carbon is a result of the combustion process in the rotary engine. If poor fuel, spark plugs or wires are bad etc. - excessive build up can happen, and cause problems. In long storage the carbon dries up and flakes off. Some times this will jam the seals in a no compression state. The local dealer will use a reverse starter on the engine to try and free it - if it doesn't work you need an engine. When we ran our auto shop we found a better way but sometimes would take awhile. Get some AMSOIL Power foam. Its an engine degreaser and carb cleaner. Spray this in the carb, and in Both TOP spark plug holes. Let sit a day and try with a breaker bar to move it. You may need to repeat the process several times- just get it to move a little bit each time. You will need to change the spark plugs - be sure to Use NGK BR8EQ-14. Be sure to have a strong battery, and once the car is started keep it running (lots of smoke will result due to the chemicals used but it will not hurt the catalytic converters). I would also suggest on your first drive to keep the RPMS up around 4-5,000 RPM to help blow everything out. Follow up with a gas treatment of BG 44K fuel injection cleaner (OK to use in Carb applications, as it will clean any residue from the tank to the engine, and help remove any remaining carbon) It is OK to use the 44K every 6 months to keep the carbon build up to a minimum.
    Should I use premium or regular gasoline?
    For a turbo you should use 91+ octane in order to avoid pinging/detonation/spark knock, etc. A good 87 octane that has a chemical additive for cleaner burning is fine for non-turbo. The Rx8 needs to run premium gas because the compression ratio is so high.
    What does your "Mild Street porting" do for performance, drivability, and horsepower?
    It gives you approximately 20% more horsepower without any significant problems in drivability.
    What are race bearings, and what do they give you?
    Race bearings are for the rotors and they are needed in any engine application that is expected to exceed 9,000+ RPM.
    What are Clearance Rotors, and what do they do?
    Clearanced rotors are used for high load engines, with high RPM, high boost, or high nitrous use. They allow for more oil flow and prevents the rotors from banging against the cast irons.
    What are 3mm apex seals, and how are they different from the regular 2mm seals? Are they already installed on the 13B turbo engine?
    The 3mm apex seals are 1mm wider than the 2mm apex seals and some people say they allow for higher RPM and boost. Typically 3mm apex seals are used when 2mm rotors are no longer within spec and their is to much space between the rotor and the apex seal. Cutting the rotors to accept 3mm seals makes the rotor like new again with the proper amount of clearance between the rotor and the seal (0.002" - 0.0035", Limit = 0.0059").
    What sort of oil should I use synthetic or petroleum based? What weight, and how long does it take the engine to break in?
    You should not use any synthetics while breaking in the engine for the first 6,000 miles and keep the engine under 4,000 RPM for 1,000 miles. After that we recommend Ams-Oil, as this is the one we have done the most testing with and have been very happy with the results. A 20W-50 should be used in the summer and a 5W-30 or 10W-30 should be used in the winter.
    I heard that a steel 10 pound flywheel is the best for street use, is that right?
    We do not recommend light weight flywheels for anything other than racing applications where you need to get high RPMs quickly, as it can wear out the clutch quickly.
    Can I use a rotor with worn out tolerances?
These apex seals were broken because they were installed in rotors that were out of tolerance. The apex groove in the rotor is very critical. The tolerance between the apex seal and the apex groove is (0.002" - 0.0035", Limit = 0.0059") For turbo applications the tolerance should be closer to .002 - .004"to resist the higher detonation probability inherent in this application. If it were to be any more than .006", it would dramatically increase the possiblity of apex seal damage, as shown in the example above.
    Do you replace bearings on your rebuilds?
    Atkin's Rotary replaces bearings in rebuilds on an as needed basis.
    Is it good to let a turbo engine run for a bit before shutting it off?
    Yes, anytime you drive a turbo engine, you need to wait at least 5 minutes to allow the oil feeding the turbos to cool everything down in order to prevent oil from being baked on causing you to need an early rebuild. If you have a tendancy to forget this then there are some really good turbo timers available, and are worth their weight in gold.
    Is there a good manual for removing and installing an engine?
    The best manual on the market is the factory workshop manual.
    I have 13B and I want to put it in a Volkswagen bug I want a carburetor what do I have to change?
    Depending on the year you will need the following:

1 - Webber or Holley carburetor kit
2 - Rotary Engine Automatic Tranny counterweight
3 - Kennedy Adapter(flywheel,trans adapter)
4 - VW Clutch=throwout bearing,disc,press plate
5 - 6 Volt VW starter
6 - 6 Volt starter bushing
7 - Bolts and nuts for Mazda flywheel,VW clutch,
8 - VW engine to tranny nuts and bolts
9 - Crossmember for front mount on Rotary engine
10 - Custom exhaust piping and muffler(flange from Mazdatrix and stainless exhaust pipe,Magnaflow muffler(must use stainless tubing due to high(2000 degrees) exhaust temp.Mufflers and routing your choice.Mine curves under the tranny and comes out under right rear fender.
11 - Custom piping for water to and from radiator(muffler shop ran mine)
12 - Hoses from radiator and engine to water pipes
13 - Radiator(I used a Mazda 3-row radiator from a RX-7 that had a Auto tranny)mounted in the front with vent where super beatle louvers used to be.
14 - Fabricate throttle linkage
15 - Wiring -from VW to Mazda(Use two manuals-VW and Mazda and just hook it up)
16 - Gas line hookup(Mazda style carbs use a return line-I used stock VW gas line for return and ran new 5/16 steel gas tubing under car along pan bolts-schools out on need for return line-you decide)
17 - Optional at extra cost=Modified carbs,special muffler,MSD ignition,Turbos,fuel injection,etc=how much money you want to spend ?
18 - Transmission=I used the stock tranny,cause its what I had.Choices are many: Type 1 bug,Type 2 bus,Porche etc.
19 - Oil cooler (Rotaries must use a oil cooler, you're choice on what cooler and where to mount.)
    I smell fuel while the engine is running, what is wrong?
    The most common problem is a fuel pulsation damper. It has a tendency to leak and can cause a fire.
    How can I prevent carbon lock?
    1) Never shut the car off before the idle drops off of the enrichment system. (choke)

2) Do tune ups every 10-12,000 miles and only use NGK spark plugs - change the air & fuel filters at this time.

3) Use the BG 44K fuel injection cleaner every 4-6 months (more if all city driving or just short distances- less if mostly freeway miles)
    How do I know if I need to replace my engine do to overheating?
    There are a couple of things to determine if the engine has been overheated to a point of needing replacement. 1. Is coolant in the over flow jug steaming or bubbling? 2. Check the plugs to see if antifreeze is on them - green goo or sweet taste (if you are that daring) 3. If you have access to a 4 gas analyzer have them seal off the over flow jug and see what the gases are in the jug. If any readings are there then it is definite. to check why overheating. 1. I will assume that you took care of the radiator. 2. when was the last time the thermostat was changed? did you use a Mazda one? 3. to check for location of heat build up use an inferred heat light and see where a significant increase is at - across the radiator - water pump - thermostat- To check for a leak the easiest way is to use an ultra violet dye and a special light - the dye will seep any where there is a leak and show up under the ultra violet light as glowing.
    What does the thermal pellet do?
    The factory thermal pellet acts like a thermostat for the oil system. When the oil is cold it does not allow full flow to the rotors for cooling, only enough for the bearings. As the oil warms up it allows more & more oil to flow. When this fails, it does so in the cold mode, thus not allowing oil to fully flow to the rotors, which overheats them and causes damage to the oil control rings. When the factory thermal pellet starts going out the thing clients comment on the most is excessive oil smoke at start up, which tends to go away as the car warms up and the catalytic conerter cleans up the exhaust. Some people even notice the oil pressure being slightly lower. Our replacement pellet keeps the engine oil in warm mode so that oil is always flowing to the shaft thus fixing the problem of the faulty factory thermal pellet.
    What should my compression test read?
    Here is a scale that shows compression pressure vs. cranking speed.

    Do you have a single rotor engine ready for use?
    Our 1 rotor engine is ready for use and it is capable of nearly 100 HP.
    Do your rebuild kits include your 2 piece apex seals or original Mazda?
    They include our 2 piece apex seals and your choice of 2mm or 3mm if 86 and newer.
    Why is water shooting out of my exhaust?
    If you are shooting water out of you're exhaust you probably have a melted water jacket seal and/or possibly a damaged rotor housing. I would suggest starting with a rebuild kit and our dvd if you wish to rebuild this. Be prepared to purchase a rotor housing, as you have a good chance of needing it. Or you can purchase a rebuilt engine.
    What kind of HP are you seeing with a street 20B?
    20Bs put out about 320HP stock, but are capable of much more.
    What is a core charge?
    It is a price that is tacked on to the overall price of our engine that you will be refunded when we receive you're engine, depending on what shape your core is in, for more on core returns please see our engine page.
    How much do you're one rotors weigh?
    Our one rotors weigh 220 lbs, more information on our one rotor can be found here.
    What is the firing order and how should the wires be hooked up?
    Number one chamber is the one closest to the distributor or crank angle sensor, number two is closest to the firewall. T is top and trailing, L is lower and leading. On the distributor cap the holes are marked L1-L2 etc.
    I tried to start my car and it just went click, click, what's wrong besides the battery or starter?
    It is possible to have a carbon lock problem. Lets start with the solutions then we will talk about the reasons.
A) Spray some Ams-Oil Power foam down the throttle body and remove the 2 top spark plugs and spray this in the spark plug holes. You may need to leave this sit over night for best results.
B) With a pry bar, rotate the engine backwards prying on the flywheel. You can access this through the inspection plate. you may need to repeat this in order for this to break free. rotating backwards then forward after adding more of the spray. Only spray for 3-5 seconds, as more is not always best.
C) Before actually starting / but after getting this fretted up, you should change the spark plugs to NGK brand ONLY.
D) After starting do not shut the engine down until the engine has dropped off of the fuel enrichment mode (fancy name for choke)

Now what causes this.
A) Poor fuel quality / or premium fuel in a non turbo. Premium fuel is now designed for slowing the burn process in turbo or supercharger applications to prevent pinging or pre-detonation.
B) Spark plugs - Wrong type, inferior brand, or worn out. Mazda advises under optimum conditions changing the spark plugs every 20 thousand miles. In Our experience in the auto service, the real miles that was combined with city and freeway driving was 15,000.
C) Check the spark plug cables - use NGK or higher quality that are form fitted - when in doubt see the Mazda Dealer. If the wires are breaking down it will not send enough energy to the spark plugs to burn the fuel cleanly.
This is known as a carbon lock. When you flood the car, carbon on the rotors gets washed off, in some cases like this it actually jams the apex seals so that they can not move freely over the protruding areas in the rotor housings and locks it up. In other instances it keeps the apex seals jammed in so that it freely turns but does not make contact with the rotor housings causing what is known as "no compression" carbon lock.
    What is included in you're rebuild kits?
    A breakdown of our different rebuild kits with prices can be found here.
    How do I correctly align my crank angle sensor?
    A) Turn the eccentric shaft until the top mark (yellow) is aligned with the indicator pin.
B) Apply engine oil to the O ring (if replacing) and install it on the crank angle sensor.
C) Apply engine oil to the drive gear.
D) Match the matching mark and the crank angle sensor on the front cover. Tightening torque 65-95 in - LB as per Mazda.
crankangleinstall.jpg (20339 bytes)
    What are the difference between you're oil rings and Mazda's oil rings?
    Our oil ring inserts are solid viton, so it can handle higher temps while Mazda's is a silicone base with a viton coating.
    Do you or can you resurface rotor housings?
    We do not resurface housings, because when grinding the housings you need to keep in mind that the surface has a thin layer of nitrating, which is a hardening process. This layer is taken off during machining and the life expectancy is very low after that. Next it is hard to get the mirror finish you need for the oil control rings, so the engine can end up smoking.
    My car is smoking a lot, what is the problem?
    In the rotary engine the oil is not only used as a lubricant but also for cooling the shaft and rotors. When the oil gets to 3 quarts the oil has a hard time taking all of the heat away from these area's and getting cooled down when passing through the oil cooler. At 2 quarts remaining the oil can actually start to break down, and not provide the lubrication to the bearings. This is when the power starts to go away. Since the rotors can not get enough oil to keep them cool with low oil, the oil O rings on the face of the rotor get damaged to the point that they can not hold back full pressure and lets oil leak by, and it burns in the combustion chamber, resulting in excessive smoke. At this time you have 2 choices, Purchase a rebuilt engine or purchase a rebuild kit.
    Will porting shorten the life of the motor?
    In most cases under normal driving conditions the street porting and polishing will not shorten the life of the engine.
    Can you put a turbo engine in a non-turbo car?
    Yes, but you would need to make changes to the computer and the exhaust system. The flywheel on the turbo engine wont fit the non-turbo tranny, then you would need the turbo driveline, third member, and axels. You basicly need a turbo donor car and it is a huge process. Or you could try one of these.
    Will a 13B motor bolt up to a transmission in a car that has a 12a motor in it?
    Yes the 13b will bolt up to the transmission but depending on the year you may need to change the Front cover and slightly modify the mounts or use a conversion bracket, in order to install the 13B engine in a 12A chassis.
    What exactly does the core need to include? Should I include intake manifolds, etc?
    The core only needs to consist of a bare block. Everything needs to be removed including waterpump, oil pan, intake, exhaust manifolds etc. If we receive a core engine with this stuff still installed we may charge you labor for removing it.
    Should I use the one piece or the two piece apex seals?
    It depends on the application, for racing the one pieces are better suited, while for street driving the two piece apex seals would be better. The reason is that one piece apex seals need to be cut down a little more to allow for more heat which will make it a little hard to start and annoying for street applications. In addition some people forget to cut them down and then when they expand from heat in the engine it can cause guaging on the cast irons.
    How many pieces in you're rebuilds are new and how many are used?
    A stock engine has all new apex seals, rotor housings are new when available. All new springs, side seals, oil control rings, and seals.
    What kind of tests are done to your engines before they are shipped?
    Each engine is compression checked and must have a 8.5 or higher (most are in the 9's & 10's) on a Mazda compression checker. Then it is pressured tested for any possible coolant leaks into the engine, if it passes this stage, the openings are taped and the engine is ready to ship. The engine compression readings are marked on the lower portion of the rotor housings. We also keep an engine build sheet on each engine, showing the parts replaced and the compression readings and the engine builders name and specifications.
    What options do you offer to improve performance and reliability?
    86+ cars have a known problem with the thermal pellet, all of our engines have the Atkins replacement that prevents this from being a problem. Most people that just want a little more power with out hurting the emissions, or derivability opt for a street port & polish. This can increase your performance up to 20%. The only draw back is if you have a lead foot your gas mileage will suffer. Most people enjoy this performance. If you ever opt to go for the Racing Beat streetable exhaust, it will perform better, with the porting.
    How can I identify the different type of injectors
    They are color coded, see this page for the specifications. Fuel Injector Identification
    I want to use a different year of rotors in my engine, what do I need to do?
    You would need the new rotors as well as new front counterweight and rear counterweight/flywheel to correspond with the new rotors.
    Is it ok to run my motor without a thermostat?
    Running the engine without a thermostat will kill it quickly. Without the thermostat the water in the cooling system never leaves the engine to go to the radiator for cooling. So you are slowly melting the seals and in sever cases warping the rotor housings. Im some piston engines you can get away with out the thermostat...
    How much does a one rotor eccentric shaft cost?
    Since you need the whole rotating assembly balanced, we generally only sell the whole balanced rotating assembly for the one rotors, they go for about $1175.00, this includes the eccentric shaft, rotor, front & rear weights, and the balancing service. More Information can be found here
    Why does the renesis engine produce more horsepower than the rx7 engine?
    The rx8 makes more horsepower than the rx7 mainly because it has larger ports than the rx7. To make the same horsepower with a 13B engine you simply need to port and polish it and the power will be equivalent.
    Why is the renesis engine lighter weight than an rx7 engine?
    The renesis engine is not lighter than a 13B engine. This was a rumor started before the renesis came out but has since been found to be false.
    Why cant i put boost on my renesis engine?
    The biggest reason is that the engine compression ratio is way to high at 10:1. Another reason is that the apex seals just arent built to accept boost. People have had some luck with low boost at around 6psi, however any mistuning at all can lead to detonation and apex failure.
    Whats up with the teflon encapsulated water jacket seals?
    The teflon encapsulated water jacket seals were not designed with the rotary engine in mind. They are too big for the water jacket groove and can cause the cast iron to break because they are too large. We have also seen and heard complaints from customers that upon tearing an engine down with these installed after only a few miles that they fray and are no longer useable. This is why we suggest using stock Mazda waterjacket seals, they were designed for the rotary engine, and work well.
    How do i install your thermal pellet?
    With the belts on the car, and the pulleys in place, carefully remove the hub nut, and the thermal pellet will fall out of the engine. Place a couple of drops of red lock tight to the bolt, check the hub bolt to ensure that the washer is centered. Insert the pellet replacement blunt end into the shaft and skinny end into the hub bolt, and reuse your old spring. Tighten the hub bolt to 60-85 ft/lbs. Note: removing the belts and/or main pulley will cause unnecessary extra work to the project including but not limited to end play damage and timing mistakes.

    How can i check the coils on my rx8 to see if they are bad?
    Use a voltage meter and the chart below to determine if your coils are good or bad.
Positive Negative  
B C  or 0 ohm is abnormal
C A 0 to several kilohm (continuity) is abnormal
    Where can i obtain 93-95 (FD) Rx7 apex seal springs.
    There is no such thing as specific 93-95 Rx7 apex seal springs. They were the same from 86-95 turbo and non-turbo. The side seal springs and corner seal springs however, were 93-95 Rx7 specific.


Atkins Rotary Specialties
41026 Ski Park Rd E
Eatonville, WA 98328
P: (360) 832-1990


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