imloggedin

did you even read my freaking post? when i bought the car, i DID blow out the oil injectors, i DID put new lines on, and i DID rebuild the OMP. the OMP WAS NOT WORKING until i replaced the o-rings. IM MAKING A FREAKING STATEMENT that they are not indestructible, and after that i even attested it probably lasted 130k miles with hardly any maintenance. you SHOULD NOT have to do all of what you mentioned with every tune up. that is completely ridiculous. your air filter comments is stupid because you didnt read what i said. if the line falls off (which has happened on EVERY rx7 ive ever owned) you have unmetered air in the engine (a very small amount), and if dirt clogs the hole its sucking the air through then you have a less atomized injection. WHICH IS THE INJECTORS PURPOSE. also i did say "compromised a bit" because i realize if all this fails the pump will probably still pump oil into the engine, just not as nicely as premix would.

now go away you pest

do i have to qualify everything i say so stupid jackhole post ****** like you wont try and make everyone sound like an idiot. OMFGZORZ YOUR FILTER IS NOT ON?? WHATTT? HAL HAL

Aaron Cake

iTrader: (1)

No, the leaking o-rings cannot stop the metering oil pump from working. Unless they are gone, the pump will always work. Look at the internal mechanism and tell me how it could possibly ever fail.

By making several repairs at once, you invalidated any theory that it was the pump alone that had failed.

Fix them?

Unclog it? These are little things that should be checked when the intake manifold is pulled as a matter of being thorough.

There are MILLIONS of Mazda rotary engines running around on the stock metering oil system doing just fine, and there always will be. The metering oil pump on my '76 RX-7 Cosmo works perfectly, as did the one on my '78 RX-7 SA (even though it leaked like a sieve).

Or you forget to premix. Do you also know that ALL FUEL is cut during decel? So you just made that hard run up to 8000 RPM and then the throttle is closed to decel back down to ~2K. During that entire run there is NO FUEL (and thus no premix) entering the engine.

It's a minor point, but a point nonetheless.

Seriously, if every potential failure in the car is nitpicked then then there are possible failures anywhere. I wonder how many people freak out at night thinking about their metering oil pump failing but have not checked their grounds/changed their diff oil/tested their ECT sensor/replaced 20 year old fuel line/etc. ever?

Which of course has nothing to do with premixing.

You could do that anyway.

That's a good idea. I have one of those bottles as well. Used to be full of fuel stabilizer. I think I'll clean it out today and see if it will be a good premix bottle.

7dust

iTrader: (14)

Stupid Canadians.


Get oil on your car - see if I care.

RevinRx7

iTrader: (3)

No, its a null point, that time interval is insignificant compared to the life cycle of the engine. And just because its not injecting the fuel doesn't mean there is no lubrication. There is left over residual oil still covering the part. Mazda injected a minuscule amount of oil only to lubricate the apex seals and springs. It was an extremely inefficient, yet commercially viable way. The way I see it, premixing allows for total area coverage of the seal as opposed to just the pin hole.

Not necessarily true. Mazda included a lubrication system on the rotary engine from the factory. As I understand it you're telling me I need neither premix nor oil injection?


Yes I very well easily could have, but why would I want to burn something in my engine that was never meant to be burnt? So I could create some more carbon build up? No thanks.

Aaron Cake

iTrader: (1)

Mazda used two injector per rotor housing in the 2nd gen. One drips onto the apex seal directly. The apex seal smashes into that drop of oil and flattens it out along it's entire surface. The 2nd sprays into the intake stream which is to presumably lubricate the other seals.

The metering oil pump is never not injecting oil in a stock application. Even as closed as the throttles will be (idle) there is still oil flow. Apparently Mazda thought that the apex seals should receive oil during zero throttle which probably means that depriving all additional lubrication directly after a high load situation is probably not a good thing.

My point was that the fact that your TII started easily and ran fine after years of storage is not due to the fact that you were premixing. The same thing would have happened if the stock metering oil system was in place.

Carbon buildup is due to burning gasoline (a hydrocarbon fuel), not oil. The "clean" spot on the leading edge of the apex is created by the spark plug. Swapping to premix is not going to prevent carbon being produced, though sometimes it prevents it from sticking to the rotors in the short term (it's hard to say what happens in the long term because there don't seem to be any high mileage premix engines around...).

RotaMan99

You now understand what im talking about. Replacing everything in the OMP is cheap and worth the money and time so you never have to worry about it again.
I did not say at every tune up. The big tune up that you do what you first get the car is when you shoudl do this and not have to worry about again.


I mentioned nothing about the air filter.

Now you are just being paranoid. You must have read my post right? You then must understand why you need to replace 18+ year old plastic lines before something happends right? If the OMP system is maintained, which there is almost no maintenance required, then you DO NOT HAVE TO BE PARANOID! New lines will not "fall off" so you don't have to worry about "dirt" getting in the oil injectors.

Replacing the OMP parts will on the first large tune up that you do will yeild you many many years of trouble free OMP operation.

I don't make others sound like an idiot, they don't need my help. You are the one that is talking paranoia and telling others its unreliable. The OMP its self is virtually indestructable, not talking about the "o-rings", im talking about the internal mechanical parts. O-rings DO need to get replaced just like all other "rubber" gaskets and o-rings.

RotaMan99

You right the there is residual oil and there is no combustion so the oil stays on the seals longer on decel then during the combustion cycle, but the exhaust of the compressed air at the exhaust port (yes there is still compressed air during decel) will force the residual oil out into the exhaust.

So now, thinking of how many times one seal makes it around at 6000rpm during decel, there is a large chance you are wearing your seals down.

I premix my self and know this issue which is why im going to run 2 stroke through the OMP.

NZConvertible

One of the strongest cases against premixing is the dubious info repeatedly posted by it's proponents...

Did you forget that half of the oil is injected into the airstream in the primary intake ports? Just like premix in fact...

You've just completely contradicted yourself. If the amount truly was "miniscule" compared to premix (and it's not), then how is it inefficient? The fact is premixing needs to use more oil than the OMP system (because it's not applying any directly to the moving parts), and hence is less efficient.

RotaMan99

I would say true most of the time except for engines that are boosting. The Oil probubly oozes out of the injectors instead of being a "spray" since the check valve in the injectors for the metered air is closed. Right?

Aaron Cake

iTrader: (1)

The injectors never really "'spray". The form a drop at their output which is either picked up by the apex seal or falls into the intake stream.

What's interesting is that with the Renesis, Mazda hs moved to two injectors at the outer edges of the rotor housings.

RotaMan99

Reason I say spray is because the air hose on the injectors has vacuum applied to it at the injectors so the high velocity airflow through the injector and tube should force the oil into a rough spray. Kind alike blowing through a straw with a little bit of water droplets in it, except that theory is a little reversed from what is happening.

The OMP seems to pump a fair amount of oil into the engine when at WOT or when the OMP lever is maxed, I find it hard to believe its a "drop of oil" when it seems to be oozing out at a steady rate and being forced into the air streem by the high velocity airflowing through the injector.

Delphince

I've been running Quicksilver premix for the past 60000 miles, which I started doing at the 100k mark after a thorough cleaning of the rotors. When I finally get around to installing the bt motor, I coud do a teardown of the atmo and let you know what the rotors look like.

Since everyone else is giving their opinions... I keep a long-necked funnel and a 16-oz empty bottle (Penzoil multipurpose 2-cycle oil in specific, it has a fluted spout so not a drop creeps around the neck and onto your hand while pouring) in the passenger storage bin, and a gallon of Quicksilver behind the passenger seat. $20 to the cashier, 8-10 oz of oil goes in the bottle (depending on gas prices), a shot of gas from the pump to fill it most of the remaining way up, cap and shake, then pour into the tank via the funnel. The gas in the bottle makes it mix in the tank better and leaves a lot less behind on the funnel for the cleanup. Chase with some gas in the funnel, then pop in the nozzle and start filling. One paper towel to clean the funnel flute and outside, a second paper tower twisted up gets yanked through the neck, then everything gets put back in the car and about 5-10 second later the pump nozzel clicks.

Adds one minute tops to the normal refuel experience, and I have to do this about 8 times a week since I do delivery (compared to the guys that complain about dealing with a premix refuel once every two weeks). It's not bad when you get used to it.

As for the people who as at the gas station what I'm doing; it's really rare. But when it does happen, I tell them the car uses an independant oil system and the stock management was never ideal. They always say at that point they've never seen anyone else have to do that for their RX-7, to which I reply 'you don't have to, and how many RX-7s do you still see driving around?' The conversation either ends there or turns in to a pleasant engagement because I aroused their curiousity.

HAILERS

Stuff and nonsense in my opinion. The oil injector in the rotor housing is located on/in the area of the intake stroke . The rotor is causing a suction all thru the intake stroke. Oil is being sucked into the chamber during that stroke. It is not just a drop being wiped off when the apex seal comes by. That's why there is suction at the top of the oil injectors. Suction coming FROM the rotor housing.

And for what it's worth and I'm just repeating myself from other threads......................The OMP itself makes pressure. I used to think it was minimal pressure also. But, I blocked off the feed from the front cover and installed a feed tube into the omp body and fed it from a bottle BELOW the pan. The oil gets sucked up from the bottle into the pump and then to the omp lines. That more or less proves the omp pumps oil by itself.

Next thing was to undo the above and remove the blockoff plate from the engine oil feed and remove the bottle mentioned above. I left a piece of tubing on the omp where the bottle was feeding the omp. About a foot long and tied above the omp.

The next thing to do was pull the banjo bolts off three of the omp lines and install three common bolts into those three omp holes. That left one omp line coming out of the omp. I installed a piece of three foot tubing on that one banjo bolt. I then inserted a nylon tube from a SunPro oil pressure gauge inside that line. I started the engine. I was surprised to see about five psi right after startup on the SunPro. Hurrumph. Rev'd the engine to two grand. Oil comes up the line from the omp towards the SunPro. Pressure increases til I saw forty psi.......then the nylon line came out of the omp feed line kersplat.

At no time did any oil rise in the tube that once fed the omp by a bottle, proving the ENGINE oil pump does NOT supply the pressure seen in the omp lines.

Any doubters can just get off their duffs and do it themselves. I've been there..done that. The OMP creating noticable pressure is why during BOOST the omp DOES inject oil in the rotors. Forty psi is considerably more than what RX boost figures are.

imloggedin

first of all im not talking about a maintenanced OMP, this whole time ive meant the stock OMP. if you wanna maintenance something ofcourse itll work. check all that crap every tune up. go right ahead, i dont care. now...

i dont need to tell you how it will fail. im telling you it happens and i could care less what anyone says. spread misinformation if you want. its not indestructible. theres no prequalifiying "oh that OMP will last forever if you replace the o-rings, lines, injectors, every XXX miles." of course the OMP wont fail if you do that. THE SYSTEM is not indestructible. LOOK UP THE WORD INDESTRUCTIBLE. "IMPOSSIBLE TO DESTROY"

wrong. i did not make them all at once. dont make assumptions. read it again. i replaced the lines. the lines had no oil in them after a few drives (running premix). i replace the o-rings on the OMP and after the first drive they were full. i dont care how people think it works. the system does fail.

now then it wouldn't be indestructible would it. thats like saying "a rotary engines indestructible if you replace all the engine seals and do a complete overhaul every 50k miles and if something goes wrong with it you fix it, but yah its indestructible."



again^^^^^

and people have been running premix for years. if you dont like it get a new ecu. show me a case that an engine died because of it.

imloggedin

refer to my last post

then what other filter were u talking about? we're talking about the filtered air LINES, and the only filter used with those is the AIR FILTER. oh i forgot about the magical rainbow filter, and the puppy filter, it makes unicorns fly out the exhaust.

again not indestructible.

babble babble

yah and i KNOW that if they arent replaced then the system can fail. again, not indestructible.

imloggedin

the training manual specifically says the injectors atomizes the oil. i would call that more of spray than a drop.

imloggedin

good work. im glad someone finally figured something out. it was all being pumped out where the o-rings are on my engine then. there was tons of oil around that area.

flamin-roids

It would seem like having the oil injected into your engine seperately would be a better idea than mixing it in your gas. I'm rebuilding an engine and I'm a little torn between keeping the pump or running premix.

flamin-roids

I have all of those by the way.

dw89s5

why is everyone getting so upset?
if u want to fix the omp u can do it once and (probably) never have to look at it again
or u can run premix and add it everytime u fill up

and untill i see some evidence there isnt really a "better way" to do it, its mostly just preference its your car run it how u want damn it

84stock

iTrader: (5)

I premix because I don't want to worry about omp failure (seen that on a friends car) and more so because I run a camden and it helps to lube the charger's teflon seals (much like our apex seals) as well. I had another friend with a camden on a 12a and when he did a rebuild he needed new housings. I rebuilt his charger and the teflon seals were completely worn down. Atkins just has you wire the omp part way open when you do the conversion. I feel if he had done premix all along the charger would have been awesome (mine looks like new inside) and the housing much better as well.

NZConvertible

Well I never used the word spray, but it's not an oozing drop either.

The whole thing about the check valve closing under boost is ridiculous. I have no idea where that came from. The check valve closes when the pressure in the chamber is greater than the pressure before the throttle (where the air lines are fed from), i.e. during compression. During the intake stroke the pre-throttle pressure is always greater than the pressure in the chamber, so air flows from the TB through the air lines, through the nozzles mixing with the oil, and into the intake runners or chambers. This air will be at high velocity, so it will break up the oil into small droplets

The FSM uses the word "atomise", which according to my dictionary means to "convert (a substance) into very fine particles or droplets". Think is the way a paint gun mixes high-velocity air and liquid paint to form a fine spray of atomised paint. I doubt the oil nozzles are as effective as a paint gun but the idea is the same.

So far you're the only one using that word. Nobody ever said the OMP was indestructible, only that failure of the pump that causes oil to stop flowing is extremely uncommon. Also these comments were about the pump itself, not the "system". Nobody has ever implied that 20+yo untouched lines and nozzles are going to be in perfect condition.

If you stopped yelling, ranting and cursing, people might take your arguments a bit more seriously.

imloggedin

maybe you should read the thread again. I SAID indestructible from the get go. I WAS QUOTED and no one ever said a damn thing about indestructible being the wrong word to use. dont give me this 'replace the o-rings/lines/injectors' crap cause thats not at all what i was talking about originally. OFCOURSE the systems going to work.

yah that doesnt look like anything is implied to me.

i didnt come here to argue i came to state what ive seen happen so people dont get the wrong idea about the OMP. then all the post ****** on gods green earth have to quote me and act like OMG YER SO STUPID THAT DOESNT HAPPENZ. OMGZORS U DUMMY.

go away, your just mad about the other thread.

Aaron Cake

iTrader: (1)

To clarify, what I would be looking for is an engine assembled with brand new parts (new housings, lapped irons, new seals) and run it's entire life on premix in standard day to day driving. Obviously this is a tall order to fill. An engine that has spent half it's life using one then gets switched to the other really don't offer much help in this long-standing debate.

I think that when I say "drop" people are thinking of a dripping faucet or similar. The drops would have to be very small. I would think that at high engine speeds it's probably more like a mist, while at lower speeds it's probably more like droplets. Could be wrong though. Either way it works.


Yes, I remember reading this in a previous thread. However in this case the pump was moving fluid into a fixed volume, thus creating pressure. In the stock system the lines are open at the other end (injectors...).

I'm really not sure what any of this means.

I didn't say "indestructible", I said "can't fail". There is a major difference between the two. I've seen a bunch of dead metering oil pumps, but always caused by some outside physical influence such as over torquing the mounting bolts or letting junk flow through it. I have never seen (in the considerable amount of rotaries that I have worked on) a mechanical metering oil pump fail. I've heard of one...the shaft broke I think.


I did, several times in fact. Your original post is unclear and offers no indication that there was passage of time between the repairs. You say something like "I replaced the lines then I rebuilt the pump". It's easy for someone to miss the meaning when reading something like that.

Sounds like there was trash in the pump. Yes, I guess this could be considered a pump failure but again, there was nothing physically wrong with the pump.

No, it's not. Not even close.

I'm not sure what an ECU would have to do with lack of premix during fuel cut? All EFI systems have the option to cut fuel during decel and should be set up like that. If not, then you are just dumping raw fuel through the system causing bucking, backfiring, wasted fuel and nauseating the drivers behind you.

The training manual also says that the pulsation damper (another contentious item that seems to confuse people) is there to dampen the "sounds" created by injector operation. My point is that sometimes things get lost in translation.

I would hope that no one is getting upset about a discussion that has happened 10,000 times with always the same result.

Bingo.

HAILERS

Just a word or two......when I blocked off three of the four omp lines and measured the presssure coming out of just one tube, I was proving to myself that the pump has the ability to make more pressure than the boost created by the turbo, and therefore in MY mind means that, there being more pressure at the omp line than in the chamber, that oil will still be entering the rotor chamber during the inake stroke. No matter how much boost the turbo is making (talking a max of what? fifteen psi from the turbo).

And an added remark about using an alternate reservoir other than the stock omp feed from the engines pan..............there isn't enough room in the engine bay for a reservoir of a decent size. I'm talking a container of a half gallon minimum (too much maint time spent on anything of a smaller size). Been there, messed with quart containers.........too much mucky muck time wasted filling it .Gone back to stock omp.

A simple gallon container located in the spare wheel well,(spare stays there also) with a simple washer pump feeding into the gas fillers vent line makes more sense. Simply turning the washer pump on for twenty seconds gets the job done with no physical interface with the oil and the container is of sufficient size to be maint friendly. Falls under common sense thing to do.