I've been thinking about putting in a bypass or remote dual stage oil filter that will keep the oil super clean..

the bypass filter would either be an OilGuard Filter
or an AMSOIL Spin-On Bypass filter.

The other alternative which I like even better is the dual stage filter called the Amsoil Dual Remote Oil Filtration System.
It combines the bypass filter with a full-flow filter. According to the product description, "it draws approximately ten percent of the oil at any one time and traps the extremely small, wear-causing contaminants and water that full-flow filters can't remove."

Because these bypass filters filter oil down to less than 1 micron (90% of engine wear is caused by dirt/metallic particles that are 5-15 microns in diameter), I'm thinking this would virtually eliminate engine wear caused by dirt/metal particles in the oil.
The rotary engine, being touted as extremely reliable, will be even more reliable, right?

Aside from being a cost effective alternative to frequent oil changes, I really like the idea of always running with clean oil, which is a proven thing with these sub-micron filtering bypass oil filters.

I want to know if there is anyone here who has experience with bypass oil filters and what your thoughts are...

Is there any reason why I should not do this?

Obvious concerns I am curious about are:
1. warranty issues
2. rotary engine issues (will this be okay on a rotary engine)
3. performance issues
4. installation issues
5. cost effectiveness

Let me know your thoughts!


thanks in advance

Dual remote and some bypass systems have reduced effective oil pressure or volume. This is not good.

Installing the bypass is equivalent to reengineering your oiling and filtration system. This is an instant warranty void. If you have money for lawyers and court, go for it.

Another thing to consider is that by removing 10% of the oil for bypass, you will remove the same amount of oil volume and pressure that is needed for lubrication, and engine cooling by the oil.

The rotary doesn't create massive amounts of wear like boingers. So, any wear that supposedly is reduced is probably not happening. Bypass is best for vehicles that have huge oil capacities, that don't have the pleasure of frequent change intervals, and that have much surface area(cylinders, valvetrain...) for wear.

The rotary doesn't need super duper filtration. Regular maintenance intervals with quality fluids/filters are enough.

The always clean oil is a farce. Additive depletion is a point of concern. Oil viscosity isn't perfect over time. Regular maintenance is better.

Originally posted by deadrx7conv
Dual remote and some bypass systems have reduced effective oil pressure or volume. This is not good.

According to Oilguard FAQ:

Engine oil pressure will not be affected by installation of the OilGuard bypass filtration system. The flow rate through the OilGuard bypass filter is approximately 1 quart per minute. This only represents 5% of the oil flow from the pump. The principles used by OilGuard’s bypass filtration system are proven and reliable.


Installing the bypass is equivalent to reengineering your oiling and filtration system. This is an instant warranty void. If you have money for lawyers and court, go for it.

According to OilGuard FAQ:

Engine oil change intervals are only recommended and not required by manufacturers for warranty purposes. Only the condition of the oil needs be maintained at certain minimum specifications during the warranty period.

By using the OilGuard bypass filtration system and monitoring your oil through oil analysis, you can maintain an oil quality that far exceeds manufacturer requirements.

Specific acknowledgments have been received from all major engine manufacturers that the installation of the OilGuard bypass filtration system will NOT affect your warranty.


Another thing to consider is that by removing 10% of the oil for bypass, you will remove the same amount of oil volume and pressure that is needed for lubrication, and engine cooling by the oil.

It's not *removing* 10% of the oil for filtering, for the dual stage bypass filter, the oil flows 100% through a full flow filter and 10% of that flow is diverted to the bypass filter by which the clean oil is released back into the stream. You seem to think by adding the bypass filter you're working with 10% less oil volume. The car will be working with the appropriate volume once the gear is installed and the oil is filled to normal operating levels.


The rotary doesn't create massive amounts of wear like boingers. So, any wear that supposedly is reduced is probably not happening. Bypass is best for vehicles that have huge oil capacities, that don't have the pleasure of frequent change intervals, and that have much surface area(cylinders, valvetrain...) for wear.

The rotary doesn't need super duper filtration. Regular maintenance intervals with quality fluids/filters are enough.


This is simply not true. Every car will benefit equally from a bypass filter producing clean oil.


The always clean oil is a farce. Additive depletion is a point of concern. Oil viscosity isn't perfect over time. Regular maintenance is better.

According to the Oilguard FAQ:
Additives are oil soluble and therefore cannot be removed by the OilGuard bypass filtration system. In fact, just the opposite will occur. The OilGuard bypass filtration system will help extend the useful life of the additive package by maintaining contamination far below levels that would cause additives to be depleted. It’s simple logic. By continuously purifying your engine’s oil, additives work less, and therefore last longer at providing their intended benefits.



I don't mean to sound argumentative, but everything I've read tells me this is something I should do if I want to run my car 200,300, even 400k.. I particularly put alot of miles on my car each year (around 35k). This would run the car down to the ground in a few years, which is why I have such a strong intention to do what I can to preserve the car's reliability. One of the main reasons why I went with the RX-8 was the overwhelming confirmation that the engine is more reliable than the normal piston engine.

I have been reading (and hearing) several testimonials saying they have benefitted greatly from having a bypass filter. A friend of mine has an old chevy Nova with a Frantz filter (uses toilet paper rolls!) and it is still running good with over 300,000 miles on the car.. The oil is always clear and the engine probably is super clean from the inside, one would suspect.

My biggest concern is, again, any factual basis that doing this on an RX-8 would be a no-no.

Fascinating info which I have not considered for any car and I am a real car nut. Most regions will have a rotary expert mechanic and this is the person to get an opinion from not the 26 year old at your local dealer. I am going to check with my local rotary "guy" for an opinion. Where would you locate this contraption. Similarly I want a K&N air intake system to draw cold air (not hot engine air which ruins any hp gains). The K&N thread indicates there is no room for a cold induction system.






Velocity Red, r/b,6spd, GT, Enthusiacstic and happy owner since 8/11

you would acquire these bypass filters primarily through an authorized dealer or directly purchased through their website...

the bypass filters that are applicable for this application are Oilguard and AMSOIL brands, both of which have online sales directly from their main website.

Oilguard return taps into the valve cover, oil fill neck, or oil pan. See oilguard installation instructions. That 5% bypass is LOST for lubrication and cooling.
If you want to loose 5% cooling and lubrication, go for it.
Amsoil uses a flow restrictor in the dual remote bypass which results in lower oil pressure in the engine. I don't believe that this is an issue with Amsoils single bypass but haven't seen proof of that yet. Several installs of the dual Amsoil have resulted in low oil pressure. Search bobistheoilguy forums for info.

If your engine fails due to a cooling or lubrication issue, warranty VOID! Oilguard mentions engine manufacturers and not vehicle manufacturers. Ask oil guard for proof(acknowledgements) that Mazda said that its ok. Feel free to battle the required vs. recommended in a court room. Anyone here read their warranty info including the small print. Most people here probably haven't even opened up their owners manual.

Try arguing with Mazda that 5-10% reduction in oilflow/pressure/cooling didn't affect engine longevitiy, lubrication or cooling, which are major killers of most rotaries.

Additives deplete over time. Bypass doesn't prevent this from happening.
Visit theoildrop forum for independent proof and info on UOAs that show additive depletion with bypass filters installed.
Visit the puradyn bypass filter website for other info. Puradyn is the only bypass filter with TBN additives built into the filter that leaches into the oil preventing additive depletion.
The other bypass filter manufactures are hoping that regular oil consumption/topoffs and filter changes/topoffs will provide fresh oil that should prevent additive depletion.

Comparing a bypass filter from a boinger engine and expecting the same results with a rotary isn't good enough. Engine wear is different. Hell, many rotaries rebuilders reuse engine bearings if in spec since most failures are seal issues(overheating cooling seals and carbon lock apex/side seal). Bypass filtration won't prevent the biggest cause of engine failures in the rotary.

All bypass filtration does is make the owner more abusive to common sense maintenance.

If your're too lazy to change your oil or keep it topped off, don't. See what happens. In 12-18 months, we'll start seeing more frequent engine failures on this website. Rotary ignorance causes engine death.

deadrx7conv is right on the money. Oil is given a different workout on a rotary engine than a piston engine.

Since the moving components of the engine spin instead of slam up and down, there's less stress on the bearings. But, engine oil plays a major role in cooling the engine - that's what cools the insides of the rotors. That's why rotaries have very sizeable oil coolers standard.

Of the 15-20 engines I've rebuilt or gone through, NONE have failed due to a bearing problem. Here's the hit list of engine failures -

- Overheating. This is bigtime bad news - warped housings, and water getting into the combustion chamber that ends up rusting the seals into the rotor. You end up with an engine that's all junk.

- Broken apex seals. This is mostly on turbo RX-7's - detonation will break the tip off an apex seal, making the engine lose compression. New rotor and rotor housing, new seals, engine's good to go.

- Broken seals due to heavy carbon buildup. Typical on underdriven cars - you REALLY need to wind out the engine on a regular basis. Running a good fuel injector treatment can also help out as well.

- Worn or missing oil seals. This is really the only oil-related failure, and it's usually caused by being lax about oil changes and running around with the car low on oil. Low oil increases oil temps, and when it gets too hot the oil control O-rings on the rotors deteriorate. With the seals gone, the motor dumps oil into the combustion chamber, resulting in a lot of smoke. These are good rebuild candidates, as everything has been well lubricated :).

Just use a quality easily-available filter (I use Purolator PureOne) and change the oil reguarly, and you'll be fine. I would also flush/fill the coolant every year - you let coolant sit too long, and it starts corroding the aluminum in the housings. This is VERY evident on teardown - I can tell when an engine's been cared for.

I'm not saying the Amsoil filters are bad, but you're just overengineering the system when there's no need to. Hell, my '86 daily driver has 190,000 on the engine and I rebuilt it at 168,000 due to bad oil seals (I bought it like that). The bearings and all the hard parts were in GREAT condition, and the engine is VERY strong now. Even with the abuse it went through in the past, the engine wasn't really affected besides the oil seals.

Dale

that's exactly what I wanted--some hands-on advice on the matter.

If what you're saying is true, which I have no reason to believe it isn't, then adding the bypassfilter wouldn't be a wise idea and a waste of money.. I'll certainly look more into this and find more hard data using bypass filters on the wankel before I do anything...

Anyway, thanks for the advice guys

that's exactly what I wanted--some hands-on advice on the matter.

If what you're saying is true, which I have no reason to believe it isn't, then adding the bypassfilter wouldn't be a wise idea and a waste of money.. I'll certainly look more into this and find more hard data using bypass filters on the wankel before I do anything...

Anyway, thanks for the advice guys




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DITTO!

Velocity Red, r/b, gt, 6spd owner since 8/11