Vaccuum pump block off pic

[vph]

During a rebuild we wanted to install a higher volume oil pump from a '90 16V 2.0L.  Since the vacuum booster for the brakes had been removed to make room for the turbo, Rod built a block off plate with a thrust bearing in it to cover the vacuum hole and provide a thrust surface for the oil pump shaft.

He made the bushing by getting a couple of pieces of aluminum, one 3/8"x3" flat bar and one 1-1/2" diameter rod, and taking away what didn't look like a thrust block.  Then he had a welder stick'em together.  The 1/2" flanged bronze bushing was store bought, and required the aluminum to be drilled 3/4" to match the outside diameter of the bushing.  He determined the length by measuring the distance from the vacuum pump flange to the drive gear face and subtracted the length of the new splined gear.  

Below are pics of the bottom of the plate or thrust surface and of the installed plate.  The installed one is a little dark.  
http://home.comcast.net/~ridenbug/pics/r_eng/r_eng_5.jpg

http://home.comcast.net/~ridenbug/pics/r_eng/r_eng_7.jpg

[Black Smokin' Diesel]

Nice. But how do you stop the thing if you don't have a break booster/vacuum pump?

[vph]

We swapped the master cylinder for a manual brake master cylinder. Then rebuilt the front calipers, new rotors and pads.  It stops great.

[RabbitGTDguy]

very nice! very clean. You might find a few others on here that may want to do the same thing.

Joe

[fspGTD]

Very nice fabrication work on the custom block off plate!    But I am a little curious, why you guys didn't just use an OEM VW distributor/vacuum pump hole blockoff plate?

[TDForNow]

Nice. But how do you stop the thing if you don't have a break booster/vacuum pump?

 :twisted:  Push HARDER !! He-he-he!

[vph]

Rodney can take the credit for the fab work.  As far as "why" make the block off plate, it was just easier to make one than to find one.  It does look cool though!  

I have read so much good and helpful info on here, I just wanted to share a little something.

[fspGTD]

Ah, that makes sense!

It sure does look cool.  Probably a few ounces lighter than the stock all-steel version as well.

[vph]

Did the original block off plate have a thrust surface?

[fspGTD]

It did, it had a flat machined surface for the thrust surface with two thin radial channels (probably only a few thousandths of an inch deep) for oil film to spread out over.

Unfortunately I can't find a good pic of the thrust surface, but this diagram shows the overall cross-sectional shape of the plug:


The OEM blockoff plug is visible in the upper-right of this pic (along with splined 1.5 diesel oil pump):


The OEM blockoff plugs can be found in 16V motors or from old 1.5 diesels that didn't have vacuum pumps.  Part number is 068 103 113 B.

IIRC, the 2.0 16V application used a 36mm gear depth oil pump, while the 1.8 16V used 30mm gear depth.  The old 1.5 D used a whimpy 24mm gear depth.

The drive gear however is different between the 16V and 1.5 diesel (pretty sure the helical gear teeth are cut in opposite directions).  On a diesel application the diesel gear with the diesel intermediate shaft is necessary to make the oil pump run "forwards".  The intermediate shaft I'm pretty sure turns in an opposite direction on gasser applications.  Hope this info helps... good luck!

PS - After I switched from vacuum pump style oil pump to splined, I noticed a small drop in "hot idling" oil pressure with the new pump.  I suspect it's because of the extra oil consumption used by this extra thrust surface.  I'm curious if you experience the same thing with your setup.

PPS - your engine build-up is looking VERY nice.

[vph]

It seems that if the gear for the pump will mesh with the one on the intermediate shaft that the pump should work.  I would think because of the shape of the gears that they would not mesh if they were opposite.