[T3] 73 type 3 auto trans IAD?

Jim Adney jadney at vwtype3.org
Sat Jul 15 12:43:18 PDT 2023

On 15 Jul 2023 at 12:14, William Jahn wrote:

>  The issue now is the IAD has so much play on the lever side it binds once
> the engine cools down after a drive but it seems to work fine driving and
> it does not stick again until the next cool down. However I am certain
> there is a good amount of a vacuum leak there, plus it has to affect the
> TPS in some manner even though the play is at the cable end.

Sounds like a really good option would be to send the worn IAD to one of the 
people who rebuilds carbs and can sleeve/bush the butterfly shaft. This is a 
standard job for those folks.

>  I have two options. Use the 73 I have or to use the 72 manual trans. The
> problem with that is it does not have the two vacuum ports for the auto
> trans. It has bosses for them and I can drill the holes and tape for 1/16 "
> NPT and install them. It's more work but can be done and I can swap the
> auto trans lever over .

Drilling and tapping sounds like a lot of work, plus you would have to get the 
ports exactly the right size and one of them has to be positioned exactly 

>  I know the answer will be use the 73 which is the easiest but In also want
> a spare so I can modify the 72 IAD ..I don't really need the kick down
> because I never use it ,

I agree that the kick down function is of limited use.

>  I am going to try to swap the IAD without removing the runners. It has
> been  done, it's just not as easy. 

If your runners are nicely lined up with the IAD ports, it won't be too hard.

> I'm not sure about the intake
> gaskets , I put new ones on in mid 2019 so as long as the paper on both
> sides lives they should be fine. If not then I need two more of these. I'm
> just going by the Bentley stating they must be replaced anytime the runners
> are removed. I never tried reusing them so I don't know.

I reuse them whenever possible. If the paper is torn, scrape it all off and glue 
new paper and press against a flat surface. Trim when dried.

>  The only question in all of this seems my best bet is using the 73 IAD. I
> did try to loosen the two small screws on the 73 throttle late but on this
> one they are peened to they will not come out without filing the peen off
> this seems to be done to keep them from falling out . The 72 manual trans
> are not peened. I guess this was some after thought. .

I thought they were all peened. The peening may have been different in '72.

I still recommend getting someone who does this work regularly to do this. 
Sure, you could probably figure out how to do it yourself, but how many tries 
would it take you to do it well? I figure I have to do a job at least 3 times to 
get it right.

You could figure out what the screw size was and buy a bag of 50 from 
McMaster-Carr, then practice on some of your other IADs. Once you were 
set up to do this, you could offer this as a service to anyone. Or just find 
someone who has already gone thru all this pain.

Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA

More information about the type3-vwtype3.org mailing list