save the whales, SAVE YOUR MOTOR
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... http://img141.imageshack.us/img141/3513/46345105.jpg 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. http://img141.imageshack.us/img141/1043/61864425.jpg 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: http://img140.imageshack.us/img140/5985/19556115.jpg 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 http://img413.imageshack.us/img413/1121/93555530.jpg which led to this http://img413.imageshack.us/img413/6519/30988463.jpg note the broken pieces of the apex seal embedded in the rotor and just how much carbon build exists. which led to this http://img705.imageshack.us/img705/6568/95606502.jpg 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... http://img141.imageshack.us/img141/1043/61864425.jpg presto... your rotor will look like this http://imagizer.imageshack.us/v2/102...921/4k7Mh7.jpg 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. http://img153.imageshack.us/img153/7646/020y.jpg so you have two options here are the results of the two options... http://imagizer.imageshack.us/v2/102...924/bVJ4tr.jpg 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 |
Originally Posted by zammm
(Post 9801644)
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 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?
|
Originally Posted by Howard Coleman CPR
(Post 9801589)
no CPR motor leaves without the EOP being deep sixed. howard 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!!! :D |
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?
|
Originally Posted by turboIIrotary
(Post 9801863)
i think our cars will go into limp mode if we unplug the omp or am i thing of a s5?
|
so what do we need to do to remove the EOP? apexi ecu will be able to do it? ty
|
Originally Posted by Mahjik
(Post 9801883)
You need a programmable ECU to remove the OMP.
|
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..
|
Originally Posted by zammm
(Post 9802071)
.theres completely stock engines with 130k+ miles with the OMP..
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 :D 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?
|
Originally Posted by Ceylon
(Post 9802190)
Another thing to add to the list.
Just ordered the block off kit from Banzai..I wonder how many they will sell today :D Anyone know what exactly I will need to do on the commander (PFC) to disable OEP? Thanks Howard :) |
Originally Posted by sbnrx7
(Post 9801964)
This just got expensive. Damn.
im glad i premix sure it makes people look at you funny but ive had not a single engine problem :nod: |
I think any of the aftermarket ECUs will get rid of codes....am I correct?
|
Originally Posted by arghx
(Post 9802157)
I think mods accelerate carbon buildup. Porting, aftermarket tuning, etc.
On the flip side we have had engines come in from race cars that constantly see 8k-9k RPM and the rotors are virtually clean. With or without the OMP. We do recommend removing the OMP and running premix. Mostly because on vehicles with the PFC (or other aftermarket EMS) there are no error codes and the ECU will not go into limp mode if the OMP has failed. This leads to a quick engine failure. Additionally cars with larger injectors should be premixing as I am not thouroughly convinced that the PFC is capable of increasing the OMP flow based off injector sizing. If you are running 1600cc injectors and it is still only flowing for 850cc then it is not supplying nearly enough oil. The only fields the PFC has for adjusting the flow rate are "Oiler vs Water temp". The AEM has a field for establishing the % increase flow for injector sizing, but the manual still recommends blocking the OMP and running premix. |
Benefits aside ( and yes it looks obvious ), do you think a car running pre mix can pass emissions?
|
it would be very helpful for many readers of this thread if someone could explain how to fool the stock ECU into thinking the EOP was working.
i know there is someone out there w the answer... let's hear from you. howard |
can someone post a guidline or something for premixing? amounts and type of oil etc. i premix for my vespa but i dont kno whow to do it with a car
|
I think i know the answer to this but i just want to be 100% clear. I have a PFC so i just need to unplug the electrical connector to stop it from pumping?
|
Originally Posted by Howard Coleman CPR
(Post 9802274)
it would be very helpful for many readers of this thread if someone could explain how to fool the stock ECU into thinking the EOP was working.
Originally Posted by duval7
(Post 9802283)
I think i know the answer to this but i just want to be 100% clear. I have a PFC so i just need to unplug the electrical connector to stop it from pumping?
http://banzai-racing.com/store/media...mp_bop_kit.jpg |
To add what Banzai was saying. My first Rx7's was a 88 base model automatic. I knew nothing about rotary's but I really liked the car for its lines and cleanliness. It had 80k miles and was in pristine condition.
The engine lost compression 2 weeks after I had it. WHY? The previous owner was a 60 year old man who always babied it. The addition of an automatic transmission made it that much easier for it to be limped around. Rotaries love to rev, they run rich, and they inject crank case oil from the factory into the chamber...... This combination can create a scenario for loads of carbon.... and a dead engine. |
Originally Posted by Seamoan
(Post 9802275)
can someone post a guidline or something for premixing? amounts and type of oil etc. i premix for my vespa but i dont kno whow to do it with a car
Use the search button.... the info has been stated 456,332,212 times on the forum. |
Originally Posted by duval7
(Post 9802283)
I think i know the answer to this but i just want to be 100% clear. I have a PFC so i just need to unplug the electrical connector to stop it from pumping?
A PFC acts differently than a stock ECU. You will not get CEL's with many of the factory sensors unplugged, such as the OMP, emissions equipment, and ABS. If you already have a PFC, just unplug it, block it, and premix it. ;) |
Howard,
How many miles were on your 500+ hp engine when you took it apart, and found it to be in nearly perfect condition? Thanks |
Originally Posted by Seamoan
(Post 9802275)
can someone post a guidline or something for premixing? amounts and type of oil etc. i premix for my vespa but i dont kno whow to do it with a car
http://www.mazdatrix.com/q-supply.htm |
HC, your pics are very impressive and I agree that 2cycle is best but, for comparison sake, weren't you running 20% meth 80% pump on that engine? As you said, AI cleans carbon from the engine... Also, automatics aren't run as hard and besides, properly tuned engines like yours don't have excessively rich afr conditions which contribute to carbon deposits.
I'm using a PFC base map and its very rich, I also still have the omp working and add 8oz 2cycle per fillup (about 18gallons), my 11 heat range spark plugs fouled pretty quickly which I think was because of the combination of richness, extra oil and cold plugs. Is it detrimental to premix while the omp is still working? When I reconnected the water injection the missfires cleaned up in just a couple of injection events. |
Originally Posted by Seamoan
(Post 9802306)
I did
Any quality 2-stroke mixing oil will work fine. Castrol, Supertech, etc.... 1/2 oz. per gallon of gasoline. Dump in oil, fill tank.... |
Originally Posted by neit_jnf
(Post 9802321)
HC, your pics are very impressive and I agree that 2cycle is best but, for comparison sake, weren't you running 20% meth 80% pump on that engine? As you said, AI cleans carbon from the engine...
Driving style has more to do with carbon build up, then anything else. Here are a couple rotors from similar engines. Both had 60K miles. The first was modified early and was seeing weekend track time, tuned PFC, stock twins, full exhaust. Notice the thin layer of carbon: http://www.banzai-racing.com/2008_cu...ront_rotor.jpg This is from a completely stock car, that was never redlined. Engine locked up at a stop light. This same engine, the secondary turbo was so caked with carbon that it could not be spun. Notice the thick layers of carbon: http://www.banzai-racing.com/schauss...ront_rotor.jpg For comparison, here is a rotor from an engine with similar mileage, with a single turbo, v-mount, 1600cc etc, running premix: http://www.banzai-racing.com/2009_cu...rear_rotor.jpg This does not mean that premix is a bad thing. Again I feel that any car with upgraded injectors should be running premix. Changing the oil is critical if keeping the OMP in place, obviously. |
What about changing the OMP to pull from a reservoir? Will the stock ECU still throw a code?
|
Originally Posted by NissanConvert
(Post 9802452)
What about changing the OMP to pull from a reservoir? Will the stock ECU still throw a code?
|
"How many miles were on your 500+ hp engine when you took it apart, and found it to be in nearly perfect condition?"
a good question.. i put 4000 mile on my 09 engine. including two dyno sessions, total of 44 2000 to 8200 4th gear runs. i will say that my prior engine that i removed and inspected at the end of 08 was in the car for four years and 15,000 miles looked exactly the same. i have never blown an engine that i have built. "automatics aren't run as hard and besides, properly tuned engines like yours don't have excessively rich afr conditions which contribute to carbon deposits." agree. "Is it detrimental to premix while the omp is still working?" no. premix is 2 cycle oil and it's beauty is that it completely ("ashless") leaves the scene. premix is great because it works all the time. my view is that even if you drive hard and run a trimmed fuel map the EOP should go. as i said, half of the motors i disassemble are carbon choked and the other half still have too much carbon. all of these motors had a working EOP. another plus is... i believe Mazda recommends against synthetic oil. it is my understanding that this is because Mazda believes synthetic oil has no place in the combustion chamber by way of the EOP. assuming this is a correct reading the elimination of the EOP allows the use of synthetic oil. it would be absolutely great if this thread didn't veer into an "Oil" thread as oil like apex seals attracts comments like blood in the water attracts sharks. and 99.9% of the posters (including me) do not know what they are talking about. when i get into those areas i tend to be pragmatic. i became attracted to Mobil 1 synthetics when they came out and i was racing. Mobil 1 sponsored me as they wanted to see how their products worked in a rotary under racing conditions. my engines ran 7000 minimum to 10,000 max for 35 minute races. i ran a dry sump w 12 quarts of oil. i was attracted initially to Mobil 1 because the USAF was having problems w the nose wheel bearings on the F-15 Eagle. they tasked Mobil to build a wheel bearing grease that would withstand the tremendous forces. which they did. good enough for me. i run Mobil 1 in my crankcase, Mobil 1 in my trans/diff and Mobil 1 in my wheel bearings. everyone has a "go to" guy. my guy is Jose LeDuc. i have had the good fortune to count him as a friend for the last 6 years. Jose has never steered me wrong. Jose runs a 2000 pound 2 rotor RX3 drag car. it has run 7.54 at 186 to date and his engines make well over 1000 rwhp. perhaps the most impressive metric is how many runs he gets from his motors before he tears them down. when Jose tells me to do something i do it. there are only a few things where Jose says, "do this period." one of those moments concerned oil. "howard, run nothing but 5-30 Mobil 1. period." it works for me. the way i build my motors they have alot of oil pressure anyway so i don't need the usual racing 50 weight. my engines make 80 pounds of oil pressure at 8000 rpm. 55 pounds warm at idle. anyway, i have this belief that synthetics are superior so i like the idea that by removing the EOP you can run synthetics in the crankcase. that's another plus, IMO, re the EOP removal. howard |
"What about changing the OMP to pull from a reservoir? Will the stock ECU still throw a code?"
i do like this idea... and i would still premix as it works all the time. as Chris has mentioned, i don't think you would run into code problems and you would not have emission issues if you just pumped 2 cycle thru the EOP. |
In one of the previous premix vs. omp threads I read something like factory set-up injects oil in the exact spot where lubrication is needed whereas premixing is not doing that as precisely as the omp set-up.
|
running the OMP to push 2 cycle oil is still a waste of time, the OMP only lubricates the center of the apex seal/slot.
the difference is that if you start premixing at the start of the engine's life you will notice that carbon has a very difficult time sticking to the oily rotor face. if you even start premixing later on in the engines life the engine will already be carboned up but the new carbon entering will have a more difficult time sticking to the carboned up areas because they are oily. also moving parts like apex seal slots will be able to decarbonize themselves. don't waste your time with the OMP even if you try to convert it, it was a bad system even for the "lazy people" as i like to call them. running premix in your fuel makes sure that ALL internal components are lubricated, not just a small spot in the seal slot. after 25k miles on my engine i wiped the rotors off and reinstalled them, there was 0 carbon buildup on them. keep in mind i started premixing oil at the start of the engine's life. i'm sure there is an easy way of eliminating the OMP with a potentiometer, i just have never taken the time to figure out what signal the ECU needs to see to keep it out of limp mode. if anyone knows i'm sure i can find a way of emulating the signal. |
after reading the diagnosis chart it looks like the ECU simply is looking for a 1.1-4.2V input from both the stepping motor and the position sensor.
installing potentiometer on each of these 2 circuits can easily send the proper signal back to the ECU. potentiometers can be found at radio shack for about $3 each and you would need 2. the outside pins on the potentiometer are for power and ground(doesn't matter which is which) and the center pin is for the emulated signal back to the ECU. after the potentiometer is installed you simply dial it in and read the voltage coming off the center pin back to the ECU, which probably should be in the middle range somewhere around 2.5 volts to compensate for wiring and heat resistance variations. so both the stepping motor and position sensor should have a 5 volt reference, a ground and a output back to the ECU. using those 3 wires for each it should be easy to trick the ECU even if you have a stock ECU without having to keep the POS EOP sitting in your engine bay somewhere looking out of place. i'm just not sure why no one has bothered to figure it out as of yet. |
Hmmm...
Thinking of ditching my 2 stroke engine bay tank and just making a bigger catch tank. Let's keep the info flowing! |
Originally Posted by Karack
(Post 9802551)
i'm sure there is an easy way of eliminating the OMP with a potentiometer, i just have never taken the time to figure out what signal the ECU needs to see to keep it out of limp mode. if anyone knows i'm sure i can find a way of emulating the signal.
|
All times are GMT -5. The time now is 04:26 PM. |
© 2024 MH Sub I, LLC dba Internet Brands