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Astra Z19TD Vacuum pump drive adaptor - Printable Version

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Astra Z19TD Vacuum pump drive adaptor - Mayhem - 03-14-2015

As mentioned in another post, the timing belt idler pulley melted, delaminated the timing belt and introduced the pistons to the valves in my Mum's 2008 Holden Astra.  I've recently found out that Holden only imported 2000 of these from Europe, where they are made and sold under GM's other brands Opel and Vauxhall.

All of the cylinder repair places here told me the same story - no parts available and nothing they can do.  Doubleboost helped me find a couple of options in the UK and I've just placed an order for a fully rebuilt head, head bolts, head gasket, water pump, camshaft pulley, camshaft position sensor, timing belt kit and other necessary gaskets. One other thing that I need is the drive adapter that enables the vacuum pump for the brakes to be driven off the camshaft, as this one gave up when all hell broke loose.  Unfortunately, you cannot buy them separately and have to buy the vacuum pump (another $90).

It is very simple and the tolerances are so low (i.e. this thing is a sloppy fit) that I could make it with the lathe, a hack saw, drill and a file.  If I pull my finger out tomorrow, I may have the mill operational next week.  Or at least operational enough to make this part.  I've drawn it up but for some reason Draftsight is not giving me the usual control on how the dimensions are displaying.  I'd welcome feedback on the drawing if anyone spots something I have missed.  I'm unsure how to dimension the chamfers but these serve no purpose that I can see.  The radiused groves are there to relieve stress as far as I can tell.  Sorry for the crappy pictures.  I didn't realize they turned out so bad.


I don't see any need for the detail on the bottom of the part either. It sits on a perfectly flat surface. 

Here is my drawing - remember, I'm not Ed: [attachment=10294]

RE: Astra Z19TD Vacuum pump drive adaptor - EdK - 03-14-2015

(03-14-2015, 09:43 AM)Mayhem Wrote: ...remember, I'm not Ed:

And consider yourself lucky. We only need one of me around here, or anywhere else for that matter. Big Grin


RE: Astra Z19TD Vacuum pump drive adaptor - EdK - 03-14-2015


Here's one way to dimension chamfers. Solid Edge 2D has a chamfer dimensioning tool to do this.



RE: Astra Z19TD Vacuum pump drive adaptor - DaveH - 03-14-2015

It's a good drawing Darren Thumbsup 

RE: Astra Z19TD Vacuum pump drive adaptor - Highpower - 03-14-2015

It's too bad those ears are centered. I would have been tempted to adapt a distributor drive from a Honda, but the ears are off-set on those.  Sad

Darren, did you say this is a SOHC and not a DOHC?  1.9L turbo-diesel correct?

RE: Astra Z19TD Vacuum pump drive adaptor - PixMan - 03-14-2015

Looks like you'll need both a 3mm ball mill and somewhat long 3mm end mills, so in keeping with tradition here you may be spending $100 on tooling so you don't have to spend $90 on the new vacuum pump.

Good job!

RE: Astra Z19TD Vacuum pump drive adaptor - Mayhem - 03-14-2015

Ed - I'll have to look into the options in Draftsight to see if it has a chamfer dimension option. At the end of the day, these are not critical.

Willie - yes, 1.9L SOHC turbo diesel. I believe the DOHC has a nasty habit of snapping belts!

Ken - the tolerance is very generous on this part, so those features will most likely be completed with a 3mm drill.

RE: Astra Z19TD Vacuum pump drive adaptor - Roadracer_Al - 03-15-2015

On drawing chamfers, I usually describe the width of the face of the chamfer and the angle. I try to describe the angle so it relates to the chuck or vise as the part is held in the machine -- that way I don't have to do math on the fly... always a recipe for disaster. I find that my projects turn out better if I spend more time doing thoughtful drawings.

This, according to my high school drafting teacher, which was 35 years ago.

That internal chamfer on the rectangular socket looks like it's probably for ease of assembly. Looks die cast. Lots of funny fillets in that part. Obviously a pretty mission critical part, I'd definitely make the replacement out of some stout material. Forged titanium perhaps? lol...