Having Problems with a Andrews Cam
Thomas C. Kummer
Having a bitch of a time putting in a new cam. 1st Andrews cam had a pit
on one of the lobes had to send it back. Well got another one and replaced
the inner cam bearing with a B138 pressed it in with a Trock Tool. Bought
a new pinion gear to match the size of the Andrews cam gear over .108 pins
2.7490. Put it together and shimmed it to .015 end play. I used the old
rocker box rubbers incase I had to resize the pinion gear due to tight a
fit on the gears. I had no ticking or whining so I tore it down to install
the new rocker box gaskets. Well I found the two center cam lobes on the
closing side have developed a mark that is across the lobe that looks like
a pit left by a bad roller bearing in a race. Tore it all out and could
not see any damage on the tappet roller. What happened to cause it?? I
don't have a clue did I miss it when the cam was new? Anybody got an idea?
Whose cams would you recommend I sort of lost my will to put another
Andrews cam in. e-mail if you got any Ideas to explain it or something
else to check
tom...@worldnet.att.net
Andy Kino
On 23 Jun 1997 00:20:01 GMT, "Thomas C. Kummer"
<tom...@worldnet.att.net> wrote:
IMHO you sound like you know what the hell you're doing, and I doubt
very much that something is wrong at all. From the gist of your note
you seem to be on the money in the way you are installing the cam.
(Perfectionist-like work on your baby) The thing thats difficult to
understand is how the hell did it develop a pit in such a short time?
Is it a pit? Or a wear mark or what? I've seen both. Is the mark going
completely across the very top of the lobe? If something was seriously
wrong, you would think the engine would make a strange noise or
something. Hope to hear more from you on this.
Andy
Scott Drysdale
In article <01bc7f68$83174d40$bb5b93cf@tck>, "Thomas C. Kummer" <tom...@worldnet.att.net> wrote:
>Well I found the two center cam lobes on the
>closing side have developed a mark that is across the lobe that looks like
>a pit left by a bad roller bearing in a race. Tore it all out and could
>not see any damage on the tappet roller. What happened to cause it??
i just had my bike apart (valve job and tappet roller rebuild), and the
cam lobes (from outermost to innermost) are front exhaust, rear exhaust,
front intake, and rear intake. so your two middle lobes are rear exhaust
and front intake, which is kinda mysterious. my cam has visible
wear marks on all lobes, but the marks are equally light on the two
intake lobes and equally heavier on the exhaust lobes.
if your new cam has faster and higher lift, it would require stiffer
valve springs to prevent the tappet rollers from losing contact
with the cam lobes at the highest point and landing a little bit
downhill. such behavior could cause the marks you're seeing, but i
would expect it to happen on both exhausts or both intakes, not one
of each. it also shouldn't happen except at high RPMs. but that's
all i can imagine causing the problem, unless those two tappet
rollers are bad and are skidding on the cam lobe at the point of
highest load instead of rolling.
// Scott Drysdale // Visual Networks Inc // Software Engineer
// sdry...@visual.mctec.com // 60 HD FLH & 57..69 HD FLH // AMIGA!
Paul McPhillips
Thomas C. Kummer wrote:
>
> Having a bitch of a time putting in a new cam. 1st Andrews cam had a pit
> on one of the lobes had to send it back. Well got another one and replaced
> the inner cam bearing with a B138 pressed it in with a Trock Tool. Bought
> a new pinion gear to match the size of the Andrews cam gear over .108 pins
> 2.7490. Put it together and shimmed it to .015 end play. I used the old
> rocker box rubbers incase I had to resize the pinion gear due to tight a
> fit on the gears. I had no ticking or whining so I tore it down to install
> closing side have developed a mark that is across the lobe that looks like
> a pit left by a bad roller bearing in a race. Tore it all out and could
> don't have a clue did I miss it when the cam was new? Anybody got an idea?
> Whose cams would you recommend I sort of lost my will to put another
> Andrews cam in. e-mail if you got any Ideas to explain it or something
> else to check
> tom...@worldnet.att.net
Sounds like you did everything right so far and one of the few that know
how to do it correctly. From what you have described, it sounds like the
Hard Facing is gone off the lobes.
I am not a big fan of Andrews Cams, though I have a few old ones hanging
around, but they make geat tranny's & other parts
Next time try a Crane or S&S for Evo's
If it's a Shovel, I like Sifton Cams.
Andrews has had some problems the last few years, I don't know why.
I would also check your new pushrods, did they give you the correct
ones.
Also check the bottom of the Lifter blocks while you are down there for
cracking on the two ears that stick out.
I see that you changed your pinion gear also. When you put in your new
cam, try this if it's not to expensive or pain in the ass. It works!!
1. Put your original pinion gear back on.
2. Press the gear off the original factory camshaft at a machine shop or
your local Air Force Shop.
3. Take the gear off the new cam also. (scribe alignment points)
4. Press your original gear onto the new camshaft, be sure to index the
cam correctly. Now all the gears mesh together like they were born.
I've done this to many bikes. In my mind this works best.
Good Luck You can E-Mail me direct. I am glad to help a fellow
serviceman
P.S I got my 2nd Harley and my only new one from the PX also. Rode for 3
years in Germany then brought it home. Great deal or what.