John---My reply, all "20 lines of it", got bounced for being too long. I'm not
going to shorten it to satisfy the "program". I guess is should delete the
original post before sending in my reply.
Dick
-----Original Message-----
From: janah@att.net
Sent: Saturday, January 31, 2009 4:04 AM
To: Sally or Dick Taylor
Cc: 6pack@autox.team.net
Subject: Re: [6pack] Rockers or Rollers?
Hi Dick,
Thanks for the reply. My engine has been apart since August and is at the
shop. Just delivered pistons, bearings and more money - yikes!
But we are starting to think about the head. I did try setting valve lash,
but it still sounded like an old sewing machine. Maybe that is what these
engines all sound like, I don't have enough experiance to know. Since I am
doing a complete teardown and rebuild, I think I have some options. I could
have the rocker assy, rebuilt - they turn the shaft back to round, chrome it
for hardness and bush the rockers (~$125 delivered). The price is right, but
if the tips of the rockers are worn a rebuild will not correct this. How much
of a problem is this? The next route, is to replace the rocker, springs and
shaft. This is about $225. Finally I have seen these Holland & Sharp roller
rockers (1.5 ratio) that can use the shaft, springs and pedastals. So if I
replace the shaft and get the roller rockers, I think I am looking at ~$480.
Not sure what to do here. If one of these strategies - even the more expensive
ones - were to promise to get rid of the clatter, I would take it. On the
otherhand, since I will be replacing the pushrods and tappets, maybe things
will be much better anyway?
John Cyg.
-------------- Original message from "Sally or Dick Taylor"
<tr6taylor@webtv.net>: --------------
Janah---It would probably more costly to get your rockers rebushed than
purchasing new (stock) ones. Take a look at the rocker shaft, as these usually
wear out quicker than the rockers. (Measure the shaft, or move the shaft down
into an unworn area to see if it feels less loose). Stock rockers can give
many miles of good service, and are a good bet. As others have wrote, the
rollers are mostly for changing the ratio, and or part of a high performance
cam go-along.
> There are some side benefits for these that can reduce valve guide wear
> I'm guessing that the "clatter" you hear is not really "tappet" or cam
follower noise, but some looseness in the rocker and shaft, along with
flattening in the face of the rocker tips. Check the valve lash to be sure you
can't adjust out of
> this.
> The pedestals can last "forever". And the springs between the rockers can do
a good job. Spacers in their stead do little if any to improve performance.
> Marketing claims for these spacers say they reduce friction. I would think
> keeping the rocker tip to valve stem more consistant and would be a more
valid
> point for race engines. I have no way of proving or disproving any of this
> rambling!
>
> Dick
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