red bull

Help please… I have removed the 12a engine and transmission from my 1983 RX-7 (series 1?) and will have mounted this in my Lotus 7 project car. I will be installing DCOE Webbers and since I have a SB100 license (kit car street legal) I am exempt from all the smog BS.. so naturally I removed 20 pounds of confusing relays and vacuum hoses… except I can not determine what this part (see photo attached) that has two of those pesky hard plastic vacuum lines and a rod-links device to the front of the engine, just below the radiator return.

So what is this thing, can I remove it? If not how can I work around it. I do not see any functional need for it but soloist your sage advice on what this thing is suppose to do. Thanks for your help. If you interested you can check out my build log here: http://www.locostusa.com/forums/view...hp?f=35&t=7793

mar3

iTrader: (8)

It's called the Oil Metering Pump (OMP)....rotaries can't use splash oiling for the combustion chamber rings, so a little oil is dribbled in just below the carburetor and rushes in with the air/fuel mix and that's how the rings get lubrication.

If you run premix, you can get rid of it but you have to stay on top of that routine.

If you don't want to take the chance, just clean it up and leave it alone. Just make sure to fab an input into the manifold under the carbs to imitate the function it has with the stock Nikki carburetor.

patmac6075

iTrader: (26)

Mario is exactly right.

Get a Factory Service Manual and get a better understanding of how these engines operate, they are very durable, plus light and powerful. But they need a couple of things #1. They must maintain proper lubrication....you'll toast a perfectly good engine in a hurry without proper lubrication! #2. They need proper cooling...again let one of these bad boys over heat and you're looking at a major rebuild. Finally, #3. Periodical maintenance.
If you do these 3 things your engine will not let you down.

red bull

Thank you (both) for verifying what my factory manual (that I found shortly after posting this inquary) stated. I have since read much about the OMP and the virtues of premix. I have installed my 12a into a Lotus Super 7 chassis I built, and will use Webber DCOE intake so I have questions on how I could implement an oil injector for the non OEM Webber set-up Ironically I am a mechanic on restoration Vespa's that.. wait for it... yes use 2-cycle oil injectors. They function quite the same, but in the case of an engine that will be used HARD (racing and autocross as well as street) both options have pro's and cons.

Since premixing is no big deal for me, I am leaning toward this option, but I know to build my exhaust now to help eliminate CO2 build-up (ceramic lined). The OMP is a rather crude device, but the just-in-time oil injection does resolve settling of the 2-cycle in the gas (at start-up mostly).I'd like to see if anyone has used OMP (modified to use dedicated 2-cycle oil only) for a Webber DCOE (racing beat) intake. What I read so far seems less than ideal and the Webber as two separate intakes so I would have to split the oil injector into both intakes... and venturi pressure will cause some back-flow. Now I understand all the emissions vacuum devices that were ontop of the 12a... what a mess!
Synthetic pre-mix seems like the best long-term remedy!

~John (Sonoma, CA)

red bull

Anyone implement a DCOE webber using the OMP?

gerald m

I was thinking of doing away with my oil injector system also .. The mix oil might supply enough lubrication but does it make as good a seal for the rotor as engine oil does ? The viscosity of engine oil seems much better than mix oil.. I cant imagine trying to keep up to the mix if the engine is on the street. even for my short hard runs on the dirt track I thought a little rod adjustment in the right place would give it a little extra oil ..I think I will be cleaning all parts and putting new lines on the injectors . There doesn't seem to be very many moving parts to the pump etc. I don't think they give much trouble.. Do they

red bull

I have 20+ years of working with oil injectors, albeit on Italian Vespa scooters, the theory remains the same. In a short answer, yes, they work reliably, but when I discovered that this baster takes oil from the crankcase... well hold on there baby! any synthetic 2-cycle oil will be vastly superior on any combustion engine when compared to typical 4-cycle oil that (with the exception of racing oil), has additives that will have a long list of nasty artifacts left behind when burned... presuming it even can be burned! If you are running any engine HARD, use the right oil. Now that I understand that this little bugger does, it is simple enough to either amend the oil source to a small tank of quality synthetic 2-cycle, or in my case, F-it I'm calling the bugger off, and understanding oil / gas settlement issues, I have no problem just pre-mixing oil. I'll be running this 12a HARD both street and track. My only next question will involve the issues of using safety foam (required) in my fuel cell and 2-cycle oil. I have a bad feeling that the foam will not like the 2-cycle oil... has anyone out else used a fuel cell with safety foam and pre-mix?