relax, this isn't another thead re AI... sort of.

i have often commented that carbon kills. half of the motors i disassemble are choked with carbon deposits, many to the point that the seals are locked. this week i took apart a motor w a broken apex seal. the motor and car had 22,XXX miles. the car was an automatic and completely stock and in as new condition w the exception of the motor.

it makes me a little sick to find a motor in such a sad condition and i thought it would be worthwhile to share the problem and fix.

here's the guilty party...



2.38 pounds of pump, referred to as the External Oil Pump or EOP. actually for most that still have this pump i would refer to it as Evil Oil Pump. the problem isn't the pump itself but what it pumps into our motors.



drink up! only your drink if you are running an EOP is on the left. that'd be crankcase oil. oh but you change yours every 1000 miles. i challenge you to drain your oil at 300miles and show me it is less opaque. filled with carbon and this carbon is being sprayed directly on your apex seals which need clearance to the exact thousandth of an inch. it also finds it's way to the sideseals and cornerseals. and makes your motor look like this:



you are looking at a 22,000 mile from new rotor. while it looks a tad on the ugly side consider that both rotors had 6 locked side seals and 4 locked corner seals and broken apex seals.

so the carboned up rotor led to this



which led to this



note the broken pieces of the apex seal embedded in the rotor and just how much carbon build exists. which led to this



ouch.

Mazda decided that the pumped up twin turbo FD motor needed a bit more lube. they engineered an excellent pump/delivery system. i guarantee you every Mazda engineer wanted to put a tank in the engine compartment that would be filled with 2 cycle ashless oil. it was no doubt decided that this would not be a highly popular task for buyers... and many would just not fill the tank. the answer was to draw crankcase oil. four cycle oil is not suited for combustion chambers as it leave significant residue, carbon, that when combined w the overly rich fuel mixture just gums up the motor.

you have two options:

rework the pump so it draws 2 cycle oil from a custom tank (Rotary Aviation sells such a mod).

or remove the EOP and mix 1/2 oz per gallon w your gasoline... 1 oz when you are tracking or are on the dyno.

so pick the drink on the right, bartender i will have some 2 cycle straight up...



presto... your rotor will look like this




these came from my 09 motor. no EOP (since 99). premix good old Walmart Super Tech around $10 per gallon for most of the trip upgraded to Redline the last couple of years. get yourself a few 4 oz bottles and you are set.

not only will your motor look better but the seals will move in their grooves without friction. my motor (507 SAE rwhp) was just like i assembled it when i checked it over. here is a picture of a corner seal. note how clean it is and how the spring still has all of it's arch after making 3.6 flywheel hp per cubic inch! a very happy/clean motor.



so you have two options

here are the results of the two options...



are you drinking carbon straight up or 2 cycle?

of course this wouldn't be a Howard Coleman thread if i didn't mention that AI not only is necessary to lower Combustion chamber Pressure but it is also responsible for steam cleaning our motors.

EOP = Evil Oil Pump.

no CPR motor leaves without the EOP being deep sixed.

howard

 

wow

 

Here's something to discuss: does porting an engine increase carbon buildup, due to increased overlap between the intake and exhaust stroke? This could be especially true when you have people porting their motor and then having a rich tune after that. More overlap requires extra fuel. So all those unburnt hydrocarbons are recycled back into the motor due to the increased internal EGR.

My buddy's original engine had about that much carbon buildup, but that was after 110k miles when it finally let go. Car ran on the stock ECU and only had a DP and catback during that time. It seems to me that stock motors on barely modified setups don't build up carbon at that rate.

 

I thought this was called the Oil Metering Pump (OMP)? If I premix AND also have the EOP does it still squirt crankcase oil into the combustion chamber? I drive 3000 miles on the oil and its the exact same amount that i put in it, with premix as well..

Max

 

AAHHHH...

That is the same drink my motor gets... Wal-Marts special "SUPERTECH" 2 cycle oil in the 16oz bottles for $1.99.. Nice little blue bottle with black cap...Fits right in the bin with a funnel..

I'm glad to see someone else uses it also... I just thought I was being a really cheap bastard by not spending $5 dollars a qt for Castrol GTX...

LOL

 

YES... It still squirts it in...You have to unplugg the connection or remove it completely...

L8R

 

"If I premix AND also have the EOP does it still squirt crankcase oil into the combustion chamber? I drive 3000 miles on the oil and its the exact same amount that i put in"

the pump doesn't know you are premixing.... it only reacts to manifold pressure. if you are not using oil between changes the pump is malfunctioning... perhaps the line is plugged. better the line be plugged than your apex seals

hc

 

So what is the result of no EOP and no premix or not enough premix or too much premix?

 

Ok Howard, I'm sold. I think we all are. So what is the easiest way we can delete the OMP while using the stock ECU?

 

does this mean CPR engines have no OMP(er i mean EOP)?


I was always worried when I blocked mine off and have been 2nd guessing that decision since day 1. Glad to see that I might actually be good on my early "noob mod".


p.s. I welcome the AI threads. Don't let repetition sway you from posting. Each thread about AI is infinitely intriguing.

 

Wow, now you got me hooked on trying to get this setup and getting an AI installed this summer. There goes my budget for the summer.

 

Been saying it for years..... I ditch those wreteched things on every Rx7 I've owned.

Great pics and comparisons Howard. Good to see a builder put up some visual data to support this.

One more system to fail, and it's not even a good system.

PREMIX for LIFE!!!

 

Is this as simple as unplugging the wiring, making a block off plate, and plugging the injector bungs?

 

pretty much. Banzai Racing has them for sale for ~20.00

http://banzai-racing.com/store/FD_13...imination.html

 

i think our cars will go into limp mode if we unplug the omp or am i thing of a s5?

 

You need a programmable ECU to remove the OMP.

 

so what do we need to do to remove the EOP? apexi ecu will be able to do it? ty

 

This just got expensive. Damn.

 

I don't see how this can be blamed solely on the OMP...Seems like the more milage the more damage an OMP would do...This engine had 22k miles...theres completely stock engines with 130k+ miles with the OMP..Maybe this engine was babied too much (never redlined)..or maybe the owner only took short trips and never really let the engine get to normal operating temperatures for very long..

 

an FD with 130k+ miles on stock engine? Maybe a N/A FC but FD?

who made that b/c most of us find rebuilds after 75-80k?

 

I think mods accelerate carbon buildup. Porting, aftermarket tuning, etc.

 

Another thing to add to the list.

Just ordered the block off kit from Banzai..I wonder how many they will sell today

Anyone know what exactly I will need to do on the commander (PFC) to disable OEP?

Thanks Howard

 

Awesome, i learn a lot from your threads.

 

so are you saying we should be premixing?

 

Apparently there are no settings to change