1984 Jetta , TDI WE MUST! (1.9 AHU M-TDI)

[libbydiesel]

8V, don't ignore the bit I said about removing the cold start advance piston cover.  It will leave you stranded.

[8v-of-fury]

8V, don't ignore the bit I said about removing the cold start advance piston cover.  It will leave you stranded.

Can I replace that back cover with the front cover off of another pump ?

[libbydiesel]

Yes, but better, IMO, is the flat steel plate from the AHU or similar engines.  Every time the engine returns to idle, the advance piston hits that plate.

[8v-of-fury]

Perfect I should still have one on my ahu pump.

[Baron VonZeppelin]

As things went along - i gained more knowledge and some factoids about these 1.9 TDI 1Z / AHU. Just to share in case it helps anyone.

The tensioner marks that i thought meant it was way over-tightened, actually were just the opposite. It was WAY too loose. During some pre-emptive testing - the Inj Pump jumped 3 cogs on the belt - when i was cheating by turning engine some with Inj Pump bolt.

I've used the cheat many times before - but never jumped the belt.
So thats when the pre-emptive tests stopped and i got more involved with the tensioner / belt specs. lol

To refresh - this is where the existing tensioner was set.



This is where the tensioner should set initially - with cam sprocket loose.



This is where it moves to, after cam bolt is torqued.



This where it settles to, after about 20 revolutions.



And this is the tension spec - after about 20 revolutions - with the idler/roller removed from belt path. Practically a perfect 13 units.
For reference - 1.6 spec is 12-13 units.



Luckily for this 116k pristine low miler , this condition was caught.
New Belt, Tensioner, and Roller for a fresh new start.
And an intermediate shaft seal too.


8V have you checked your tensioner setting yet ??

[8v-of-fury]

Swear to god, I have magic fingers. (it is what she said) This was the first attempt from when I did the swap.. took the picture tonight. With out knowing at all, I had the belt tension dead on.

[CRSMP5]

mmmmmm gasser motor mount... i HOPE you put a shim behind the front 2 bolt holes... the step in the mount is for the alt/ac bracket... and no shim it will BREAK those bolts/block..

[8v-of-fury]

Yessir, it allowed me to use the AHU pump mount for my IP.

No sir I did not use shims, It had no shims on my original mk1 gas motor.. why do I need them now?

Fwiw, that step in the mount was stock to ALL gas mk1 mounts AC or not. No shims were on my mount when I removed it from the stock gas motor.

[CRSMP5]

ac or alt bracket is behind that to be a shim... trust me on this... you need to do something.. it will vibrate and BREAK the mount, bolts or block.. you need to fill that gap...

[8v-of-fury]

ac or alt bracket is behind that to be a shim... trust me on this... you need to do something.. it will vibrate and BREAK the mount, bolts or block.. you need to fill that gap...

You know, you might be on to something here. Would it hurt to write in proper sentences? lol Whenever I read your posts, I think of somebody who has just run a couple of blocks and is out of breathe. Then they try and tell their story, and it has pauses after every three or four words. lol

[CRSMP5]

makes it hard to read when all the words are too close together...

ive seen what happens when the ac unit on a mk1 gassers start to pop bolt heads.. why i asked on the shim... it needs/requires something there to prevent the mount from flexing.. gotta be solid.. else that bolt head will pop off and fall into the timming belt..

[8v-of-fury]

makes it hard to read when all the words are too close together...

but it flooowwwsss lol

ive seen what happens when the ac unit on a mk1 gassers start to pop bolt heads.. why i asked on the shim... it needs/requires something there to prevent the mount from flexing.. gotta be solid.. else that bolt head will pop off and fall into the timming belt..

Sir, yes sir. I will look in to this today, as I will have the belt and pump off anyhow .

[Baron VonZeppelin]

You were damm close on the tensioner setting.
I'd have been happy to find it like that - if not knowing beforehand.
Probably within the 12 unit zone.

Since you're having it loose again - this time go for full spec.
Marker should move south of the notch a little bit, after cam bolt torque.

[8v-of-fury]

Will do.

[8v-of-fury]

Andrew, I just realized with my pump on the bench that removing the cold start advance mechanism will affect how much idle adjustment there is with the little spring inside of the pump.. I will have to crack the lid of again and remove that little spring won't  i..