Cam Gear on for lifter R&R

JShadzi at aol.com JShadzi at aol.com
Wed Jan 9 10:20:40 EST 2002


Scott, you are being a little overdramatic with this... if you read my last
post you will see that I agree with you that, overall, removing the cam gear
to replace lifters is the best procedure.  My assertion was that it CAN BE
DONE, which you stated that it COULD NOT.  Your statement was flat wrong,
I'll stand by that wholeheartedly.

Interestingly, I believe you are replying to assertions I am not making!??

End of discussion as far as I'm concerned...

Javad


In a message dated 1/8/2002 11:30:37 PM Pacific Standard Time, QSHIPQ writes:

<< Javad:
 Let's be clear here.  In the case of the 3B motor, there is no rear cover to
worry about, the rear cover is the cam cover, so an unobstructed "up" of the
exhaust cam can happen, with no risk to the "procedure" whatsoever.  The cam
seal makes this a "not recommended" procedure, cam seals should be done on
every cam removal IMO/E, it's just too cheap to pass up.  If the cam comes
out, a new cam seal goes on, even if you are doing just the cam timing chain
on the 3B, you went from a 15USD procedure, to a 20USD procedure.  Can you
"reuse" a cam seal?  Sure, but we're talking a couple hundred bux worth of
lifters so:  A) the cam seal is a fraction of the total cost, and B)
necessary lifter replacement would dictate this cam seal isn't recent.

 WRT 10v cars.  I've done lots of them over the years, and looked for ALL
shortcuts to these procedures, and I weigh these shortcuts in terms of risk
vs benefit, as well as the "can it be done".  I've lost 1 woodruff key in 20
years of... woodruff keys, so that reasoning doesn't make sense to me (sears
sells nice flex magnets to grab those, btw).  Looking in detail at your
procedure, I see a couple of problems that would indicate to me that this
procedure assumes such a high risk of damage, that it isn't a valid
procedure.  IF you are leaving the TB on the cam gear so as to not have to
retension the TB (what I'm reading with the duct tape on the belt to hold it
onto the cam gear), then as you lower the cam onto the number 1 journal you
are adding an off center loading of a steel cam to an aluminum front cam
journal.  The REASON you are leaving the TB on the cam gear is that putting a
previously tensioned timing belt on the cam gear after cam install is a
B*TCH.  Why?  Cuz it's tight.  Thinking this thru, which cam cap goes on
first in your procedure?  What is that doing to the loading of the front cam
journal?

 If you follow the Audi procedures, ALL cam journal caps are torqued to spec
BEFORE the Timing Belt Tension load is added.  In YOUR procedure, you're
ADDING TB Tension load to the front cam journal/s BEFORE you have even
installed the cam journal caps.  I wince as I reread that.

 Billet steel cams and cheap audi aluminum castings don't mate well under
load Javad.  Using any cam journal to tension an installed cam belt causes
stress on very delicate aluminum caps.

 Javad, I read what you are doing is just wrong.  If I can't convince you, I
hope your machinist can.  The 15nm cam journal tightening sequence in the
Bentley manual is the only documentation needed here.

 Major no-no Mr Shadzi.

 Scott Justusson >>



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