Type 1 Oil Pump in Type 4 Engine

All Right!  The new CV Joints came in the mail a couple days ago, and they are in and they are quiet.  The job took only 35 minutes.  It is amazing how smooth it can go when the parts actually work and fit right.  No more junk parts.

Today, I cleaned and prepped a good used oil pump to install, hopefully tomorrow, time permitting.  When I built the new engine, I installed a brand new aftermarket camshaft and cam gear, both from Webcam.  The gear bolts onto the camshaft rather than using rivets like the original from VW.  Because the bolts heads stick out a bit further than the rivets, the oil pump needed to be ground down just a bit so that it did not hit the bolt heads.  I used a re-conditioned Type 4 oil pump, which is similar to a Type 1 pump, only the gears are internal once the pump is bolted together.  The bolts on the back side of the pump needed to be ground down. 

Here is the view of a Type 4 oil pump (Just happed to have an extra one to photograph):

You can see the four bolts on the back side that hold the pump body together.  The are the four bolts that interfere with the new cam gear bolt heads:

The Type 4 pump works well, except that once the engine heats up and the various metal parts expand, the camshaft bolt heads have been hitting the oil pump bolts.  It is not enough to seize the engine, but enough to cause vibration and noise.

The pump I prepared for installation is a Type 1 oil pump, typically used in a VW Bug motor.  It will fit the Type 4 bus engine, with a little modification for the Webcam gear and camshaft.  I had to grind some material off the back side, as well as make sure the pump body and cover were flat relative to one another.  This was accomplished with some 600 grit wet sandpaper on a very flat surface.  I used our Formica kitchen table.  Don’t tell Diana.  I made sure all the sanding mess was cleaned up before she even knew I was working on car parts in the kitchen.  I have used this same pump before, but it leaked slightly as it was not flat.  I think the sanding will work.  It required that I sand the ends of the gears as well so they don’t scrap and bind on the cover.

A Type 1 pump (pictured below) is made up of several pieces.  It has a pump body, gears, and cover.  The gears are exposed until the cover is installed, unlike the Type 4 pump.  It is a lot of work to install an oil pump in a Type 4 engine, requiring a lot of the engine parts to be removed, the engine mounts and carrier to be removed, and the engine to be supported on a jack.  It is probably 2 hours of labor.  I will let you know how it works.

Ron

(o v o)