Date: Mon, 21 Aug 2000 08:24:07 -0700
Reply-To: Stuart MacMillan <macmillan@home.com>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stuart MacMillan <macmillan@home.com>
Subject: READ THIS: How to throw a rod--update and prevention
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Well, I disassembled the poor 2.1 engine I destroyed a week ago, and it
turns out the rod failure was indeed caused by a rod bolt, but it did
not break, the nut came off! This could only happen from "bolt stretch"
that allowed the nut to loosen and eventually come off.
I'm with Bob Donalds on these bolts causing the vast majority of 2.1
catastrophic failures. The "torque to stretch" rod bolts used in the
2.1 are USELESS, and even worse, a time bomb sitting in every stock 2.1
engine just waiting to go off and cause total destruction. I don't know
if they offer any assembly efficiencies for the manufacturer or are just
a "planned obsolescence" device.
When one of the #1 rod nuts came off the bolt did too of course, and it
was thrust up through the top of the case by the crank counterweights
where it was embedded, hence I was able to recover the bolt and nut and
know it did not break. After that #4 got hit by some shrapnel from the
rod and the cylinder fractured, taking out half the cam along with it as
well as knocking two more holes in the top of the case. The resulting
oil/coolant emulsion was then sprayed all over the engine compartment.
I took me all day Sunday just to clean things up in preparation for a
new engine.
So, I cannot stress this enough: For those of you that have a factory
2.1 with more than 100,000 miles on it (the consensus is these engines
are good for between 125,000 and 150,000 miles) I strongly recommend
that you do two things:
1: Install an oil pressure gauge!!! This will tell you more than
anything else about the condition of the bearings in your engine, and
can help you avoid catastrophic failure. 2: Start a savings plan for
that rebuild BEFORE 150,000 miles, and make sure that the "stretch to
torque" rod bolts are not used in the rebuild, substitute the
conventional 1.9 engine rod bolts.
Rebuildable 2.1 cores are getting scarce for this reason. If you
destroy yours it not only will be difficult to find another engine, but
it will cost you the core charge as well, at least another $500.
I have some interesting pictures of the remains of this engine, I'll
send them to anyone who would like post them on their web site if there
is any interest.
--
Stuart MacMillan
Seattle
'84 Vanagon Westfalia
'65 MGB (Driven since 1969)
'74 MGB GT (Restoring)
Assisting on Restoration:
'72 MGB GT (Daughter's)
'64 MGB (Son's)
Parts cars:
'68 & '73 MGB, '67 MGB GT