Pierburg butchery

[marcus]

I know a lot of people are suspicious of the Pierburg, and a lot of people will botch things to keep a car going, but this really puzzled me, I'm the third owner of my 1985 GTL, I've had it for about 13 years and as far as I was aware it hadn't been molested.

When taking my carb apart to get to the root of a) starting problems and b) full-load lack of power, I found someone had done this to the screw that limits the travel of the plunger on the 'throttle plate actuator', aka 3/4 point unit:

screw.jpg

The bent thing on the end appears to be part of a crimp connector, and the holes in the body of the screw between the two o-rings appear to have been blocked by brazing in a section of mild steel rod and grinding down the ends. All of this presumably to prevent the thing from operating, but why?

This is mine next to an unmolested one:

two screws.jpg

This is the bent thing when removed and taken apart:

bent thing.jpg

I'm wondering what other dirty hacks have been done... lost a Mk2 Golf to an engine fire back in 2001, where someone had played around with the carb...

Anyone have any thoughts on this beyond the usual "bin it and get a Weber"?

[james butler]

correct me if im wrong but doesnt that unit regulate the idle speed using vacuum?
if so blanking off the air way would mean the idle would be fixed and not fluctuating (according to vacuum) which was what my pierburg was doing before it got replaced due to another fault.

[marcus]

Yes, I think you're right, though I can't see how it would affect the idle on either my original or the donor carb I'm using for reference, in both cases the throttle plate lever is several mm away from the 3/4 unit plunger and since the latter can only retract I don't see what influence it could have...

[james butler]

like wise no idea but it looks like they went to great length to do it.