Mod of OMP for 2 cycle oil injection
 

Ok two things to cover.



The OMP mod.



Differences in Mazda's recommended engine oil weight 10w30 as compared to 2 cycle oil injector oil.



First the OMP modification.



Second an open discussion on the physical properties of the two oils. This is for deciding how much the actual metering is effected by the different oil weights. Not if one is better than the other. 2 cycle is designed for injection in systems designed for oil injection. Our OMP was designed for injecting regular motor oil. Clarified its about the delivery not the properties after it is injected!

Materials needed
 

Dremel tool

gasket material

gasket sealer

metal for block off plate. Aprox blank license plate thickness

Drill / bits ( I used a small drill press )

JB weld or other high temp epoxy

Gas / oil proof hose 1/4" ID

Hose fitting 1/8 NPT to 1/4

1/8 NPT thread tap

Oil storage tank

Warning
 

WARNING:



There will be allot of particles from drilling and grinding etc. I must emphasize that the OMP and its parts to include the injection ports could be damaged and or plugged by these remnants. Please use allot of carb cleaner to flush everything completely!!

Notes
 

Just to clear this up I have some paper towel in the small resvior for two reasons, keeping out debree and soak up excess oil.

Beside the OMP is the block off plate I fabricated. Insure you remove any barbs that could cause leaks!

Notice that there are only two bolt holes in the plate. If you like it could include all three holes and you will not need a spacer to make everything level.

Front cover Mod
 

The front cover will need to be modified by drilling an oil return path for oil rerouting.

Oil driveshaft breakdown
 

This is not hard to disasemble. It should be done to insure no metal has been left in this area. I used a small air compressor to ensure things were clean too. Be sure to reassemble everythng the same as before you took it apart. A camera would be excellent to ensure this!

This is what your blocking off
 

Oil path information
 

Marking the OMP for drilling
 

Scribe marks for the hole. The black dot is the location where you need the fitting.

I angled the OMP on a drill press to ensure I had room for the hose and clamp.

Ok I have a prior engagement so I have to stop now. I will return latter to finish this up.

Stay tuned!!!!!

i didnt think you would do this writeup as soon as you said you would... your my hero :)

Sealing issues
 

O-ring
 

I decided for extra sealing to add an o-ring around the input shaft on the OMP. It ended up taking a lot of time and work. I don't remember the size for the o-ring and I didn't even take pictures of it when it was done. I think the confidence in my moding skills were tested here and questioned myself if it was going to work or if I was going to screw it up. Luckily I had another OMP and I wasn’t' worried about it, sorry no pictures.



I used a dremel tool and a small steel-rasping bit. It was round and about a 1/8" across. It came with my kit and wasn't anything special. I proceeded to make a groove around the shaft area so it would be flush with the plate and almost completely recessed (o-ring fits under the plate between the plate and the pump). I assembled the whole thing on the cover several times to make sure it all fit snugly. Take your time here and use a new o-ring for final assembly.

Where the hole comes out
 

I should have included this picture with the drilling photos so here is where the hole is on the chamber side. I guess I could have taken alot more pictures now that I have written the thread!

Assembly
 

O-ring on first (new OMP o-ring too), Blocking plate next, sealent and gasket next, then bolt it all up. I your blocking plate doesent include all three mounting holes you will also need a spacer of equal thickness as the plate. Torque to specs.

things I left out of the parts list.

O-ring

2 small hose clamps.

I will always try to answer question on this mod, I have over 1000 miles with so far and it is working well!

Terry7

Nice & thanks for sharing!

:-) neil

you shoulda thanked him 2 years ago.

I wonder if it is still working well...

Merry Chirstmas and yes it is still going strong. Went to the Deals Gap rotary rally this past spring and logged over 1800 miles in four days, I also traveled to VIR in October too.

Can you verify that it is in fact injecting oil? Does your 2 stroke reservoir end up emptying slowly?

I am sure the answers are "yes" but I just like to ask for the sake of completeness.

On a side note: How much 2 stroke does your engine ingest? quarts vs mileage? How many total miles do you have on this mod?

I haven't kept up with the mileage on it. I don't put a considerable amount of miles on it in a year, say around 1200 miles. It works very well, depending on how hard I drive it. Under a lot of boost it goes down pretty fast. On average I get around two to three tank fulls of gas before it gets low. I have documented the amount I use more exactly on one of the threads. I will try to find it and direct you to it. It is kind of fuzzy right now, because it has been a while. I just check it right after I drive it or just before I drive it. Just a habit now, I never want to get it close to empty. I am pretty paranoid about running out.

I have been really wantign to do a system like this, but lack the ingenuity for this stuff. was gonna use i think... rotary aviation??? they have a adapter for outside sourced 2 stroke. ingenius idea though! thanks fro the write up!!!


Clos

I know I left use info in various thread on this forum, but this was the only one I could find. Hope it helps

Terry7

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/premix-you-guys-using-735245/page3/

2-stroke leaking into the engine
 

I did the OMP 2 stroke conversion. I fabricated a light blocking plate, glued with gray RTV silicone to the OMP and the same at the engine side. I didn't drill the front cover return line, as the OMP feeding is the last point in the lubricating circuit, increasing internal oil pressure.

The block off plate and the 2-stroke feeding nipple are very similar to the ones depicted in this thread. I put the 2-stroke oil reservoir near the wiper motor, where the cruise control actuator was, the highest point in the engine bay.

Just after the installation, doing the leakage test, I noticed that the reservoir level was slowly but definitively lowering, but there were no external leakage. The only way oil is going out the OMP should be the injection lines feeding ports (lines were disconnected), but no oil was comming out anywere. That means 2 stroke oil is going into the engine (the one hasn't been started yet because of other jobs in progress)

How can the 2-stroke oil leak past the OMP shaft and how can be it prevented? Sould I change my oil or the 2-stroke can remain in the engine without harm?

Thanks.