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General Information => General => Topic started by: TylerDurden on December 04, 2012, 12:25:32 pm

Title: Replacement hydro lifter doesn't "spring"
Post by: TylerDurden on December 04, 2012, 12:25:32 pm

Hrmmmm....

Two things I noticed when dropping in a replacement hydro lifter:
1) The replacement has a matte finish on the top, unlike the originals which are almost mirror shiny
2) The replacement does not have any give, or spring to it; unlike the originals which I can push down with my fingers.

Any tips?


(the original I am replacing was sticking. It was the lifter/follower, not the valve.)

Title: Re: Replacement hydro lifter doesn't "spring"
Post by: TylerDurden on December 04, 2012, 01:23:03 pm

Brand new from my FLAPS...

The bit in the center will not depress.

(https://lh5.googleusercontent.com/-5-8l2aRcW4g/UL5o8lTQIaI/AAAAAAAAA0Q/YkXl6TR-VZk/s640/IMG_9163.JPG)

Notice the charcoal finish on the top surface. The sides are shiny as expected.  They fit in the bores properly.

Eh?

Title: Re: Replacement hydro lifter doesn't "spring"
Post by: srgtlord on December 04, 2012, 06:31:43 pm

I think they will be fine considering they are brand new.

Title: Re: Replacement hydro lifter doesn't "spring"
Post by: TylerDurden on December 04, 2012, 06:36:22 pm

I'm feeling a bit better about em...

Closer inspection revealed that there is travel in the new lifters' springs, not nearly as much as the older ones.

New lifters: .012 -.015"
Old lifters: .090 - .120"

The shoulder surrounding the center tip seems to be crushed or folded like a turtleneck on the older lifters, allowing more travel... (maybe it's part of the design?).

(https://lh4.googleusercontent.com/-0IOIjXUUl58/UL6wWMC9CBI/AAAAAAAAA0g/0CpoV4H1y30/s640/IMG_9164.JPG)

The wear on the older tip is about .003".



The matte surface vs. the older shiny surface
(https://lh6.googleusercontent.com/-MwUUywdjxJA/UL6yXaDekHI/AAAAAAAAA0o/vEdLENtOnlM/s640/IMG_9165.JPG)

Title: Re: Replacement hydro lifter doesn't "spring"
Post by: rallydiesel on December 04, 2012, 08:13:38 pm

The matte coating is a nitride layer to help with break-in. As far as the compressibility goes, the tdi engines have the small travel. Make sure to check you have the right part # but they may have updated idi lifters to the tdi ones.

Title: Re: Replacement hydro lifter doesn't "spring"
Post by: TylerDurden on December 05, 2012, 10:25:23 am

Looks like one-fits-all these days.

Any thoughts on pre-filling the lifters before installation?

Title: Re: Replacement hydro lifter doesn't "spring"
Post by: cyrus #1 on December 05, 2012, 09:01:48 pm

I always try to fill mine.  I leave them in an oil bath upside down overnight and then try to work any air out by hand.  Make sure to let the engine sit for a couple hours before turning over to allow the lifters a chance to bleed down.

Title: Re: Replacement hydro lifter doesn't "spring"
Post by: theman53 on December 06, 2012, 04:25:50 am

always do 24 hours in atf