Just received rebuilt motor and getting ready to finish assembly and install however during the inspection and looking in the oil metering nozzle holes in the housings there are two brass "slugs" with centered holes in them. They are rather beat up looking and one has a screwdriver slot looking slit in it. These brass slugs sit about 12 mm into the threaded holes. What the heck are these?

Broken ends of the old nozzles?
Really should be there?
Previous mods to the oil injection system?

Thanks

 

hmm if they got a hole in it the its not the plugs people use to to delete the omp and oil injection system. My guess would be someone over-tightened them and sheared them off in there and then tried to cut a slot in one to remove it.

 

that's what I thought but they are about 12 mm into the holes. The hole threads look undamaged so I doubt the slit was cut in place. Tried to unscrew with a screwdriver but no joy.

 

well the head of the injector is what stops it, so without the head on it can go alot further in which would he youre problem.

 

What they look like:
FRONT


REAR



What I believe it should be like:

 

Yeah those are way down in there. Wtf?

 

well if you cant get them out only thing i can think of is putting banzai racing plugs on top of them with some sealant.

 

You'll find they're standard - rear one appears to be early housing, front a later one if there's no slot....hard to tell with the shadow.

 

Dont think ever seen this before new on me.

 

The brass inserts are in every rotor housing, however they are not usually as beat up as the slotted one that you have pictured. Someone tried to remove that one, obviously. Those are mixed housings, the one without the slot is the new style, which Mazda supplies a rubber insert for. Are you going to be running premix? If so, then it won't matter.

 

Learned something new - Thanks
I will be moving the OMP nozzles from my other motor to this one and using the stock OMP system.

So, If I should re-machine these "inserts" in place what is the bore size(s). Seems there is a larger entry and no discharge hole into the rotor chamber. A 0.0780" Deltronic pin gage fits tightly into the least deformed insert entry but bottoms out.

 

The hole is not straight through, the insert is basically a restrictor pill. They are very difficult to get out, you will probably cause more harm then good.

 

The plugs were a Mazda revision in about 1998. They found that on decell the oil cavity below the nozzles would be sucked out, a time where it wasn't needed, then as acceleration and boost followed and oil that was then needed took some time to fill the void.....hense the "filler bushing".
Barry

 

Here is a pic of the inserts, the longer one is the earlier version, the rubber seal is used with the shorter one. You can see that the oil actually exits the bottom at a 90 degree angle from the entry hole. The brass inserts have been in the housings since the 1984 gsl-se. The dimples you see in the bottoms were created while attepting to remove them from trashed housings

 

Thanks - that's fantastic information.

Looks as if I clean them up and put new rubber "seal" atop the later one and if a seal fits the earlier one should be good. Also I'll built a pressurization test rig and make sure they will blow through and flow at the same rate.