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Tue May 22, 2012 11:13 pm

I got this from pierce manifolds thinking it was a needle valve replacement part for my 44 IDFs. After installing it I noticed the silicone tip sticks. Hmm.

When comparing this 200 with the ones in the rebuild kits there are several differences. Mainly the hole in the nut exposing the needle and the silicone tip.

Q. What is the valve/needle on the right actually used for? i.e silicone tip, hole in nut.
Q. Did I get the wrong part or a better part?
Q. Should I simply use the needle valve found in the rebuild kit?

Wed May 23, 2012 12:02 am

I would think the silicone tip would seal better than the metal on metal. The only wat to prove longevity is to try them

Wed May 23, 2012 6:51 am

Does it "stick" with pressure against it?....Or just "stick" when playing with it on bench...

The hole in seat (nut), is probably to improve fuel flow (appears too be on fuel bowl side of "valve")...

Dale

Wed May 23, 2012 7:01 am

the silicone tip is a "Viton" tip, and an improvement on the all brass design. They seal better with less pressure.

Wed May 23, 2012 9:29 am

In terms of setting float height I'm planning on setting these to the standard 10-11mm closed, is this still recommended?

Dale M. wrote: Does it "stick" with pressure against it?....Or just "stick" when playing with it on bench...

The hole in seat (nut), is probably to improve fuel flow (appears too be on fuel bowl side of "valve")...

Dale

Yes sticks when playing on bench, no pressure. I was thinking the same thing, maybe not that sticky with pressure on them. The hole(s) (theres 2) end up wherever the seating surface puts them. in my case side to side i.e facing ea barrel. Either way fuel gets directed into bowl, don't think inlet hole position can be helped.

Also, John thanks for chiming in.

Unique details/differences i see: (nerdin out here)

- hole(s) in nut wall area x2 - exposes viton tip, quicker fuel bowl fill and perhaps less chance to clog above the ball if debris makes it through?
- Viton tip - slightly compressible, suggested as a better seal. Overall this needle appears shorter than standard, perhaps more material on the female side?
- ID of threaded inlet @ 3.5mm
- the Viton needle ball is retained w a slightly taller bevel and seats the ball slightly different in that, less of the ball protrudes. i.e less surface area exposed.
- the spring for the ball seems lighter by maybe 20ish%. Less pressure to move it due to extra holes in the nut body wall?
- when comparing inlet bodies @ seat with needle in to the ball, the overall length comparison between the two, looks like a .5mm diff, Viton one being the longer. (using digi calipers)
- while overall needle length comparison shows the viton one being shorter. i.e more material or different taper angle @ seat on inlet body? Female end.

These observations serve no purpose currently just here for general comments or future ref. What can I say, carbs intrigue me.

Wed May 23, 2012 9:43 am

thats the one you want.mo better.

Wed May 23, 2012 6:13 pm

Got floats set dead nutz on @ 10.5. Let's see how that fares.
Thanks guys!

Wed May 23, 2012 7:26 pm

Get rid of them, and go back to the all brass needle/seat.

http://www.thesamba.com/vw/forum/viewtopic.php?t=477305&highlight=gas

Wed May 23, 2012 10:28 pm

I've ran the viton needles and seats with E85, VP110, AVGas 100LL and have had no issues with any of the fuels. I've been running the E85 for about a yr now and the other fuels before that.

Thu May 24, 2012 12:08 am

[email protected] wrote: the silicone tip is a "Viton" tip, and an improvement on the all brass design. They seal better with less pressure.
I agree.
I've done the comparison too. Ten+ years ago when I first installed the Dellortos on my engine, I installed one brass tipped, and one rubber tipped valve. About 2 years ago, the car began to run really rich. The idle mixture screws became unresponsive. I was able to screw a few all the way in, the car would still idle. Eventually I tore the carbs apart. The brass tipped valve was the worst worn valve I have ever seen. The rubber tipped one looked new.