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RE: TR4 Cam Bearing Question

To: "Edward R. Purcell" <epurcel@bellsouth.net>, <triumphs@autox.team.net>
Subject: RE: TR4 Cam Bearing Question
From: "Pete Ryner" <pryner@ij.net>
Date: Sat, 20 Nov 1999 17:27:01 -0500charset="iso-8859-1"
Importance: Normal
Can't help you with the oil hole locations, but if the bearing is covering
them, it doesn't matter.  The bearings have to come out and be re-installed
(only if you're lucky can they be re-used)  Unfortunately, it is not that
unusual for a machine shop to screw up cam bearings - or anything else for
that matter.  I've had good shops, and some incredibly terrible shops.  I
remember a Spitfire engine I took to a shop one time (toted as one of the
best in town).  Did the same thing with the cam bearings, but also got them
in crooked so the cam wouldn't fit properly.  They then used steel wool to
"dress" the bearings to make the cam fit, broke the cam end nipple with a
hammer making the adjustments, but the cam still wouldn't fit properly.  I
had them bore to .020 over, even gave them the new pistons to make sure they
would properly fit.  You guessed it, not one piston would fit into the hole.
At least they were too small, not the reverse!  All in all, they really
screwed the whole block up.  Upon complaining to the manager, I was finally
offered to have them re-do the job or my money back.  I took the money and
ran!  Go back to the shop and ask them to fix their problem!  It's their
mistake, not yours.
Pete

'56 TR-3
'66 MGB

-----Original Message-----
From: owner-triumphs@autox.team.net [mailto:owner-triumphs@autox.team.net]On
Behalf Of Edward R. Purcell
Sent: Saturday, November 20, 1999 4:43 PM
To: triumphs@autox.team.net
Subject: TR4 Cam Bearing Question


Listers,  I need help from someone very familiar with cam bearing hole
locations.

Background:  I got my block back from the machine shop and the front
intermediate (third from rear) bearing hole is not over an oil hole.  It
seems very unlikely that the bearing is incorrect and that the machinist
would cover up an oil hole.  This bearing has two holes which are almost
180 degrees apart, therefore when the setscrew is in one hole the other
hole is in the thin part of the web.  The rear intermediate bearing has
two holes close together, one has the setscrew and the other is over an
oil hole.  Given the location of the setscrews and the oil gallery,
logic tells me that holes on opposite sides of the bearing is wrong.  I
wish I had examined and made a drawing of this before turning it over to
the machine shop.  Hindsight again.

If anyone has a spare set of cam bearings, new or used, could you check
and see how far apart the holes are on the front intermediate bearing?
If you have a block around with the cam out maybe you can feel the holes
to determine the distance.

I have checked the archives and my Haynes and repro Workshop manuals.
Any assistance will be appreciated as my last resort is back to the
machine shop.  FYI, the rear bearing is wide with 3 holes, rear
intermediate has 2 holes but is not as wide as the front intermediate
(bearing in question) which also has 2 holes.  Thanks, Ed



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