I have my engine all back together S4 after my stock one let go and I put new OMP lines on and cleaned the OMP in and out and now when priming the oiling system with a 450rpm electric drill i see no oil moving up the lines, i have read the manual and taken one apart to see how they work but after all that i still do not see how they truly work!!! I am a fairly mechanicaly adept person and have already succesfully rebuilt 2 rotories. So here they come!
Does the OMP actually pump oil or is it just a metering device?
If it is not a actual oil pump that pumps the oil up the lines then what makes the oil/pressureizes/dribbles it into the housing/mani?
I have checked all the vacuum check valves on the oil injectors what part do they play in the scenario?
Should the place where the OMP bolts to on front cover when being turned over have high/medium oil pressure at it or not?
Yes i have checked all the passage ways which lead to the omp feed/ ompdrive lube?
Yes i have oil pressure checked when priming with a gaughe in linethat loops where oil cooler should go.

If there is anymore information i need to provide to figre this out please do so ell me as i do not want to run premix for the rest of my rotorys life!!!!

Well thank you all for your time!
Keith

 

the OMP sprays a small amount of oil into the combustion chamber to lubricate the apex seals, premix is the alternative to this weary ssytem on our old cars, use the serch button for a more detailed explination.

 

did you even read the guys post lol. he obviously knows that much allready

koopz, I'm just on my way out and cant check for you, but look in the online FSM, the fsm is fantastic and has the information you're looking for.

 

It's both.
The OMP is driven via a gear on the front oil cover.
There is pressurized oil going to it via the stupid front oil cover o-ring and a passage that tunnels through the front oil cover itself.


-Ted

 

Since the pressure in the OMP lines is apparently very low, I wonder if the pump is actually there to reduce the pressure going to the injectors?

 

If you look at the design of the front cover and howw the passage to the omp thru the front cover works the gear drive that drives it and its shaft is hollow 1/2 way thru where it has a roll pin holding shaft from coming out on dissasembly, this roll pin enters the hollow part and serves as a pressure relief? so the OMP does not get full oil pressure? but does get a good flow of oil thrru a small flat spot on the shaft where oil leaks through? All of the information i have collected is just from looking at the design, i want to know how the actual pump works!!, the FSM is useles when it comes to this no exploded diagrams no anything that i could find other then how to testif it is working. I have a full binder FSM i bought from mazda when i bought the car so i useually give it a good read and find what i want before i ask anything thats the low post count lol.

I am fairly new to rotory's? maybe 2 years now but i have allready succesfully rebuilt and installed 2 engines that have come out flawlessly, and am fairly technically inclined.

I can see why people give simple answers on this forum.... mainly cause the people asking the questions are simple and in turn ask simple questions!

I am asking this question cause i have taken it all apart and still dont quite understand how the system works...

And on another note premix is not the answer for everything mazda designed it this way for a reason....

 

Yup they designed it for consumer easy and neglect. Not performance applications.

 

and then the question goes - is premix really as good as people say....
the stock mop have been proven to work for a while...

 

They stop chamber compression from leaking back out through the nozzles.

 

if the car is basically stock, the only reason to go premix, IMO, over a good working OMP system is to have a cleaner burn (burning premix oil instead of engine oil).

it should be noted that the vacuum lines going to the oil injectors help to distribute the oil as more of a spray, rather than a drip.

 

How so? Sucking on that end of the injectors will do nothing but pull the valve inside closed. So, the engine has to be sucking harder than the vacuum on the other side in order to flow oil. Are you suggesting that this forced opening of the valve is what causes a spray? I suppose I could see that happening.

 

Oh, and while we're talking about oil injectors, I have one housing injector that I can't suck through at all, and another that I can suck a tiny bit of air through. I can easily blow through them both. Is this okay?

 

yes, apparently. it's the same idea as the vac on the injectors that help "atomize" the fuel stream.
i could be mistaken but i don't see them serving any other purpose...

 

Sorry, there's no chamber compression in the intake runners. Too many answers just look at the injectors at the rotor housings.

 

You're right. The air lines on the oil nozzles are fed from in front of the throttles (i.e no manifold vac). During the intake stroke vacuum in the chamber sucks air though the nozzles and "atomises" the oil.

 

I was editing my above drivel but took too long doing so, so here's more of my drivel about oil injectors that was meant to go in the above post:

Sorry, there's no chamber compression in the intake runners. Too many answers just look at the injectors at the rotor housings.

Theres is a one way poppet valve in the injector, made of rubber. As the fsm showed you, you should be able to blow in the direction of the base of the injector but not be able to suck back from the other direction. You've seen the picture in the fsm so you know what I mean.

There is no suction from the vacuum hose on top of the injector. I'm sure everyone knows that. The suction comes from the direction of the rotor in the housing, IF your talking about the injectors in the rotor housing and NOT talking about the ones in the intake manifold.

About the rotor housing injectors: The next time you have a engine apart, take a look at the hole in the rotor housing that the oil injector feeds oil to. The tiny hole where the apex seal passes by. That tiny hole is located in a area of the housing where the rotor is doing its intake *stroke* thru the intake port. There is a very small point of time when the rotor has closed off the intake port and the tiny hole is now in the *compression stroke* (my assumption) area. It's about one inch from being closed off by the apex seal. But the intake port is now already sealed off by the rotor.

At this point I should let you know these are just observations. I'm clueless about how they work. I accept the idea that the **vacuum** hose on top of the injectors is there to equalize pressure on each side of the injector. If it didn't I think the injector would suck the oil out of the omp like a bandit and you'd be refilling you pan much sooner than you do.

OMP's and oil injectors work just fine and dandy.