Project84

I did do a search (just to get that out in the open) and I didn't find anything that really answered my question. Have a 87 N/A
On the oil injectors, the clear lines are for the oil, and rubber black ones are for vaccuum. My question is what does the vaccuum do to the injectors? If the OMP is advanced by the link to the throttle body, whats the vaccuum for?

And it should only be 4 right? one at each rotor housing and 2 in the lower manifold? This engine I picked up has 1 at each housing and 2 at the center plate. I got it short block so I don't have the manifold.

Project84

Ok, did some more reading and I think I figured part of this out. The oil injectors in the center plate do the same as the ones in the manifold were supposed to do, so I'm good to go on that part. Still don't know why it has to have vaccuum to function.

HAILERS

Sort of lost my way on this, so I can't give a clear answer. Basically its equalizing pressure on either side of the hole(in the injector) where the oil is injected. I *think* if that was not done, oil would be sucked big time into the housing.

rxseven

you have the 84-85 GSL-SE shortblock.

Project84

Thanks, I wasn't sure cause it came out of a 87 and I was told it was a S4 motor. Still looks and good, no chrome flaking at all on the rotor housings, ran when it came out, just had water seal leak. Thanks for the info guys.

91vert

I think the black hoses going to the oil injectors are pressurized air from the air pump to "blow" the oil into the rotor chamber. I don't think they are vacuum hoses. I'm pretty sure (too lazy to look it up right now) that the FSM says that you should be able to blow air through the oil injectors, but should not be able to suck air through. Kinda like a check valve.

I may be totally wrong, but that's what I think I remember reading.

HAILERS

The vacuum is coming from the rotors during their cycle. The vacuum is from the rotor chamber NOT from the throttle body. The *vacuum*hose on top of each oil injector goes to the spider. The spider runs to the large nipple on the back of the throttle body on a turbo and the large nipple on the front of a N/A. The passage in the throttle body leads to a quarter inch hole in front of the throttle plates. Therefore there is no vacuum coming from the throttle body. Its filtered air.

Yes, the flow of air is one way. Towards the rotor housing. Suction from the rotor. No air pump involvement.

Project84

I have a FSM now, and I checked it out. You guys are right. I can blow through them but not suck air. However, I do not have a 84-85 SE, as RXSEVEN originally stated. The 1st Gen motors have the water seals in the rotor housings. The 2nd Gens have smoothe rotor housings and the water seals are in the side plates and center housings.