Toilet paper oil/fuel filter.
 

yah, i know. i searched. only thread that comes up is peles thread.

hm... seems i have to buy one and see how it works out on my 7.

http://www.cumminsforum.com/articles...ter/Page1.html

the company also sells oil and automatic transmission filters.

Very interesting. Test it out. It seems like it would work great.

Why?

Stock filter does its job just fine and if you find 1 filter each year too expensive, you shouldnt be driving an rx7 in the first place...
I bet that the total coats for this mod is more than 5years worth of filters

A fuel water seperator from a diesel would work and seem more logical then tp.

One filter a year?
I wish.

I think you've found a solution for a problem that doesn't exist.

How would this not help? More minute filtering of particles is a great thing. Yeah and Furb, I change my oil around 3K and I put 30K on my car last year. So um about 10 filters actually at about 8 bucks a pop. The comments on that diesel engine are great, "Apparently your Cummings engine doesn't care how long you run the oil... Your obviously taking good care of this engine, it may outlast us all.":lol:

ok my bad, i run it only 5000km a year, thats why i only use 1 a year...

Help what? Do rotaries have oil contamination problems due to particulates? There is no existing problem for this solution to fix, therefore it is unnecessary IMO.

Due to higher fuel contamination (as a function of mileage) of the oil in a rotary, I'd think you wouldn't want to run oil long enough to make use of a bypass filter anyhow.

I don't think this is going to fix the problems associated with the stock seal lubrication system. Pre-mix is the easiest way to do that.

I vote yes.
Even if it does nothing, the chance of it doing good would be worth the cost to me, especially if your putting down that kind of mileage.

ok so the toilet paper filters the particles from the oils, but what filters the toilet paper fibers from the oil?

if you read the post you would see none of the paper fibers made it in to the oil great for piston motors not need for rotaries

I think this would be OK if your Engine runs like Crap!

^ oh god what a shitty pun...

OK, a couple comments here:

1) For anyone who thinks they can use this instead of a stock filter- NO. Bypass oil filtering is a secondary system that slowly filters the oil with a low flowrate but to a smaller particle size than the main high flow filter.

2) The problem with this is that it is largely irrelevant, ESPECIALLY on a rotary. The reason is that in modern engines, particulates are not typically the problem with oil. If the oil you are changing is coming out with enough particles in it to cause significant wear problems, you have more important issues. The lifespan of your oil is related to 3 major things-additive package, thermal breakdown, and fuel/exhaust dilution. The additive package primarily depends on the brand, type, and quality of oil, so there isnt anything you can do about that save buying decent stuff. The other two are the big ones, and in both cases, rotaries have more problems than piston engines.

Thermal breakdown occurs when the hydrocarbons and polymers in the oil are subjected to heat which causes them to oxidize or react with each other to form compounds with less desirable characteristics. Thermal effects also contribute to the loss of viscosity split which is caused by damage to the polymers that cause the oil to 'thicken' at higher temperatures. Rotaries are especially bad because they have a much higher heat rejection to oil than piston engines, meaning that oil temps are hotter and considerably more heat is transferred.

Fuel and exhaust dilution are caused by blowby, when fuel/air mixture or exhaust make it past the seals and into the crankcase. Fuel tends to dilute the oil and thin it, reducing lubricity and viscosity. Exhaust dilutes the oil, but also causes reactions similar to thermal breakdown. Exhaust dilution can also add particulates, but these damage the oil more than they do the engine itself, as they are in the form of carbon or graphite. Dilution is also worse in rotaries because they tend to run rich and have more sealing issues than piston engines, primarily because the sealing area is so much larger.


In other words, putting this on your engine wont hurt anything, but it will NOT allow you to run longer oil change intervals. The best ways to prolong rotary oil life are: Buy better oil, keep the engine cool (add oil cooling capacity if modified), and switch to a standalone ECU, allowing you to lean out the mixture. Even if you do all these things, you still aren't safe to run longer than at most 10k miles like a piston engine can, because the dilution issues will eventually damage the oil no matter what you do.

Awesome post!

I am about to send off an oil sample to blackstone labs. It's coming out of my old 87 N/A, which burns a quart every 300 miles, and smokes blue on startup. Should be fun results.