Re: 1985 Johnson 120 hp replacing the VRO pump
Mike,my motor had the non vro boss on the block, and t tapped holes to mount the 88 spl pump, but before I got a chance to look at mine I built a little manifold to mount the new one to, just in case I did not have the factory boss.
I took a small piece of 1/8 inch plate about 2"x3 1/2" and drilled and tapped a 1/8 npt hole into the center of it. I put a hose nipple, coated with red loc-tite, that the pulse hose would fit on in the 1/8 npt hole and cranked it down tight. I then ground the excess off from the inside leaving a hole for the pulses to come through, and a nipple to put the hose on, just like the VRO. I took the gasket from the new pump and layed it over the hole and marked the holes to mount the pump. I drilled and tapped them at 10-32 (I believe) and would put the pump on the manifold, and mounted the whole thing in the spot where the VRO was except my motor had the pump mounting holes and pulse hole in it. My '85 90hp had the holes in it, it's strange your's doesnt.
I have this manifold and would send it to you if you can use it, or post a picture if it will help.
I also have a three hose pump on my 55 Johnny, the pulse hose goes in a boss in the bottom of the housing. The housing is the exact same casting as the block mounted pump except they drilled and tapped the pulse boss and did not drill through the the flush mounted pulse hole. I'll put up a pic.
Here's a spare housing I had in my pickup, the pulse hose goes in the boss with the red X. If I had to do it now I would forget about the manifold and drill and tap the housing. You'll need to run a 1/4 -20 tap in the stock pulse hole and put a set screw in that to plug it if you drill and tap the pulse hose boss. Either way will get the pump working for you.
