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Discussion Starter #1
Hey folks.
I was reading a Haynes manual and it said on no account should the cam towers be disturbed. Now, I took the head in to an engine shop for a valve job and when I got it back the towers were off. I asked the guy about it and he said that it doesn't matter as long as they are put back in the same way they where taken out. Is this true?
Any ideas? Thanks.
 

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Your mechanic is right its no big deal

> Hey folks.
> I was reading a Haynes manual and it said on
> no account should the cam towers be
> disturbed. Now, I took the head in to an
> engine shop for a valve job and when I got
> it back the towers were off. I asked the guy
> about it and he said that it doesn't matter
> as long as they are put back in the same way
> they where taken out. Is this true?
> Any ideas? Thanks.
Dont worry about it, all you have to do is gradually tighten bolts WHILE at the same time turning the cam by hand.After tightening bolts to proper torque make sure cam turns freely with no binding, you will need to make sure the cam position plate is installed on front towr so that cam doesn't slide forward while turning cam. Later,norm
 

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Discussion Starter #3
> Hey folks.
> I was reading a Haynes manual and it said on
> no account should the cam towers be
> disturbed. Now, I took the head in to an
> engine shop for a valve job and when I got
> it back the towers were off. I asked the guy
> about it and he said that it doesn't matter
> as long as they are put back in the same way
> they where taken out. Is this true?
> Any ideas? Thanks.

I am thinking of what can happen if they arn't put back on right and it wouldn't be pretty, I tend to belive the manual more than the mechanic on this one. the cam tower metal is real soft compared to the cam so they wear faster than the cam, they also support the stress the cam has on it from the valve springs. Say if the middle towers got a little out of alighnment and wore out of round the cam would warp till it broke ruining the engine pretty much. They like to keep the same clearance on each one so they have a constant oil film and any error can cause a lack of oil causing wear. It would start slow and then wear very fast before it broke.
Using just the cam turning freely is not a good way to check as far as I can see. you can get enough clearance to turn it freely but what happens when it gets hot and the metal expands. If one tower is just a little off on top and the next is a little off on the bottom when the metal expands the one with less top clearance will have none on top and the one with less bottom clearance will have none on the bottom causing them to wear out of round. Plus the cam will also expand when hot to add to the trouble. I don't know if using a straight edge would be better but I'd trust that before I'd go by turning it while tightening them. I can see why manuals say not to touch these things and I will avoid it myself and let some shop that can check these things proper to make sure they are true inline before I'd run it.
 

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> I am thinking of what can happen if they
> arn't put back on right and it wouldn't be
> pretty, I tend to belive the manual more
> than the mechanic on this one. the cam tower
> metal is real soft compared to the cam so
> they wear faster than the cam, they also
> support the stress the cam has on it from
> the valve springs. Say if the middle towers
> got a little out of alighnment and wore out
> of round the cam would warp till it broke
> ruining the engine pretty much. They like to
> keep the same clearance on each one so they
> have a constant oil film and any error can
> cause a lack of oil causing wear. It would
> start slow and then wear very fast before it
> broke.
> Using just the cam turning freely is not a
> good way to check as far as I can see. you
> can get enough clearance to turn it freely
> but what happens when it gets hot and the
> metal expands. If one tower is just a little
> off on top and the next is a little off on
> the bottom when the metal expands the one
> with less top clearance will have none on
> top and the one with less bottom clearance
> will have none on the bottom causing them to
> wear out of round. Plus the cam will also
> expand when hot to add to the trouble. I
> don't know if using a straight edge would be
> better but I'd trust that before I'd go by
> turning it while tightening them. I can see
> why manuals say not to touch these things
> and I will avoid it myself and let some shop
> that can check these things proper to make
> sure they are true inline before I'd run it.

Allow me to add my two cents on this topic.First,
I think the head shop guy led you wrong by saying
it makes no difference how exact the cam-
towers are lined up...Nonsense the haynes manual
specifically says not to remove the towers
because At assembly ,those cam towers are bolted
in place, then a line-boring procedure is done.
This line boring ensures perpendicular cam
tower axies are Exactly in line with the cam-
axis',thus the cam can rotate smoothly with no
binding on any of the towers.In my opinion,
it is doubtful you will ever achieve axis
alignment through rotating the cam,...I think
you could get it fairly close ....but not worth
wasting a new cam. I suggest taking back the
head w/towers and try to get them take up the
cost of line-boring,afterall it was the mistake
of the head-shop!!

Hope I helped,

83zxt
 

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RADIAL DONT WORRY ABOUT IT

I did same thing to my car 4 years ago and the cam and towers are still fine!I rev motor to 7200 daily for last 4years it is all Okay There are little alignment dowels in the cam tower bolt holes. Later ,norm
 

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Another thig

People if you cant remove em how are you supposed to put shims under them if you shave head for straightening or increase compression.dont fret it will work okay!!
 
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