With the short block basically finished I needed to redo the intake manifold to move on. So I cleared off the metal table and got to work taking it apart. The upper intake manifold is plastic and the bottom is aluminum. I am not pleased having a large piece of plastic as a part of my engine but it has lasted over 20 years so I guess it is ok. I got the upper off and was dismayed at just how horrific it looked unerneath. Everything was covered in an oily soot. It looks like the soot from the exhaust pipe when it is running too rich but wet with gasoline. Then remembering the EGR valve, I realized that it is exactly what it is. I pulled the poppets out of the ports and immediatly broke one of the plastic clips that holds them. Great start Mr. Careful. I decided to be a lot more careful after I looked up the price to replace this “injector solution”. Crazy expensive and a crap design. The central hub is a plastic tub into which 8 injectors are forcibly pressed into the bottom. the side has a couple of connectors for the pressure and return fuel lines, and the other end has a fuel pressure regulator to create a small pressurized bath for each of the injectors to lay in while they open and close. The injector itself doesn’t inject into the manifold. It injects into semi flexible tube that is terminated by a poppet valve that opens and closes based of pressure behind it from the fuel pump / injector. The poppet is held in place by a very flimsy plastic clip that aims it towards the back of the intake valve. I removed everything from the lower intake manifold and from the injector body in turn. Everything got cleaned off and I used a burr grinder to take down some of the sharp edges on the lower manifold. I didn’t do a lot and It probably won’t make any difference in mileage but It made me feel better.
The o-rings for the injectors are a serious PITA and required Vasaline and some serious hand strength to get pushed into place. (No comments from the peanut gallery, thank you). I bolted down the hold down plate and replaced the fuel pressure regulator with the provided replacement and clipped the body into the loose fitting clip that is bolted to the lower intake manifold. I put all the poppets back into new clips and put them in the appropriated valve number cavities. Then after replacing the silicone gaskets and lubing them I placed the upper intake manifold over the injector body and pressed firmly into place until the clips clicked into place. Then a bunch of small bolts later the upper and lower manifolds are now one, and it was ready for install.
