Author Topic: aneroid pin say no (Read 11826 times)

bert · « **on:** September 30, 2006, 11:24:10 am »

Took the mk1 turbo diesel for its first drive today,impressed with it,but not too much kick as i was hoping for,so i decieded to swap the aneroid pin with a 1.6 TD one,

they are a different diameter,the 1.6 pin is a loose fit in the 1.9 pump,so what now?
I know one of you will know the solution :wink:
Bert

bert · « **Reply #1 on:** September 30, 2006, 01:07:12 pm »

Ok,if i get the pin on the grinder,what taper do i need to grind? also there is no starwheel,just the pin,diaphram,and a large sprind inside the lda.
Please come to my rescue
Bert

bert · « **Reply #2 on:** October 01, 2006, 08:40:59 am »

I dont want to be called the master of disaster :wink: tell me what to do with my boost pin please :| only the one side is profiled on my pin and the profile is almost non existant ,why have bosch changed the diameter?
Typical i have a 34 aneroid pin to drop in
Bert

RabbitJockey · « **Reply #3 on:** October 01, 2006, 09:03:24 am »

yeah the aneroid is very simple to udnerstand and stuff, definetly gains to be made with it especially if you have it matching fuel and boost very well.

deepmud · « **Reply #4 on:** October 01, 2006, 11:19:32 am »

grind your own - start small. This pic is of my previous motor, 1.9td.

I ground too far up the pin at first ( got it turned around in my head) - then went for the correct location

- I didn't go very far, and smoothed the metal with a knife sharpening stone so it would not wear the pin - just that much of a wedge plus turning up th main fuel screw had fueling to about 1100 EGT with 12 psi of boost - and it had very good power. 100 hp? Maybe?

bert · « **Reply #5 on:** October 01, 2006, 11:35:08 am »

deep mud,thats the one,im going to have it ground at a machine shop tomorrow,i presume im only needing to grind the bottom bit of the pin where the 'wear mark' is and then polish it back up,i will take it easy then try it again and see what happens,the car is in the next unit to the machine shop so i can grind and play :wink:
Bert

bert · « **Reply #6 on:** October 05, 2006, 01:30:28 pm »

Deepmud,thats what the machine shop did to my pin yesterday,the origional profile is crap,why did vw use such a useless pin? is it for economy/emissions rather than power? the 1.6 pin would have been nice but it didnt fit.
Bert

deepmud · « **Reply #7 on:** October 05, 2006, 02:15:41 pm »

IM mostly, I think - it's why the 1.9td has only 5hp more than the 1.6td.

Show us a pic of your new pin and the 1.6td pin!

I need to get to grinding on mine so I will be thinking of what profile to create.

HarryMann · « **Reply #8 on:** October 05, 2006, 07:02:08 pm »

This is good and useful stuff. Just one or two dimensions of a pin that works well for a 1.9TD would be incredibly useful (for many it seems, a hot topic

). Where to start and end the taper up the pin and the minimum diameter and offset would be brill.

jtanguay · « **Reply #9 on:** October 05, 2006, 11:11:28 pm »

I think the neatest part to customizing the taper, would be having different stages in performance. with a mbc you could control how much ooompff the car has.

ex: let the car run with normal 10 psi right, and the aneroid won't have full travel... so set the pin that way. when you increase your boost, the aneroid will travel farther downwards, and if you have a larger taper, you will get greater quantity of fuel added. stage 1, 2, and possibly 3 or 4??

HarryMann · « **Reply #10 on:** October 06, 2006, 02:38:35 am »

We're definitely getting the message on this one... a few basic dimensions to start with would be useful, so we don't go completely off the rails :idea:

This very much reminds me of whittling down emulsion tubes for nice top-end progression on Weber style fixed carburrettors - a Black Art if ever there was one.

bert · « **Reply #11 on:** October 06, 2006, 12:15:02 pm »

The profile i have had cut is difficult to explain,but here goes,the origional profile is a parallell start with a taper about 2mm long then the taper stops and the pin runs parallell again,the profile i have now is a-taper that starts in the same place as the origional but carries on at the same angle and does not finish as before,there is a sharp step where the grinding finishes,but the feeler pin does not travel that far on the pin so it dont matter,i have polished the surface back up with fine emery cloth and oil so it will not wear the feeler pin.The angle does not seem as steep as the 1.6 cone but im hoping when i drive it it will be an improvement from standard.I am running a garrett T3 turbo off a 1.6 as advised by the boys in the know off here :wink:
The pump timing is set at 0.85mm as stated in a diesel manuel,what would you lads set it at? 1.0mm has been suggested??
Thanks for all the good advice i have recieved,made me go ahead with the conversion
Bert (will let you know how it performs asap)

deepmud · « **Reply #12 on:** October 06, 2006, 12:16:33 pm »

So this time I'll take a good set of before pics, with ruler in view, and measure from the top to the marks on the rod where the pin slides on it. The cool thing about the stock 1.6td pin IS the variation of how much fuel it adds at a given boost - the offest cone lets you go up and down. I have been thinking I can get the same effect with carefull hand grinding - we'll see - if I destroy it, it can be replaced pretty easy, it's not my DD.

HarryMann · « **Reply #13 on:** October 06, 2006, 12:47:54 pm »

Thanks Bert, I'm an engineer and still don't get it :lol:

We tend to talk in pictures, that is, scale drawings with dimensions set in stone on them, but hey, I'll get a 1.6 pin, mic it all up, draw it, and then maybe soften it up a bit for the 1.9 (thats the impression I get), not quite so radical a profile - is that the idea?

Cheers!

bert · « **Reply #14 on:** October 06, 2006, 12:58:05 pm »

i was an engineer now a mot tester/ mechanic :wink:
I dont have pics of the pin,i do know the 1.9 pin is a bigger diameter to the 1.6 :cry:
Herts uk? i need to come see your project ( what you got?),next summer when i get the mk1 gtd out the garage :?
No tax at the moment but it runs ok without it :wink:
Bert. halesowen