Date: Wed, 23 Aug 2000 08:24:04 -0700
Reply-To: Stuart MacMillan <macmillan@home.com>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stuart MacMillan <macmillan@home.com>
Subject: More on rods and bolts
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I took what was left of my 2.1 to my rebuilder, Jerry at Northwest
Connecting Rod, and after close examination we determined that I had
"spun a bearing". This means that the rod bearing shell literally wore
away, leaving steel on steel, not a good thing. According to Jerry, at
high speeds this will generate tremendous heat, even to the point of the
metal becoming red hot with sparks flying off. The heat then will
either cause the bolts to stretch, nuts to loosen or the rod or bolt to
break, leading to catastrophic breakdown, which ever comes first. And,
indeed, the parts of the rod I recovered were "blued" from extreme heat!
I thought he might get a couple of rods out of it he could rebuild, but
he tossed the whole wretched mess in the scrap barrel, salvaging only
the flywheel and pulley. Jerry is my kind of guy, do things right the
first time, and don't cut any corners!
So, perhaps the stretch bolts themselves are not the problem, but
excessive bearing wear is the true culprit. That means scrupulous
attention to maintenance coupled with careful oil pressure monitoring is
the key to longevity for this engine, just as it is for any other.
This engine works very hard to push our nearly two ton rigs around, and
150,000 miles is still the recommended point to rebuild the engine.
So, I'll reiterate my recommendation: If your engine is between 100,000
and 150,000 miles, install the gauge to make an assessment of the
bearing condition, and then monitor pressure trends if things are within
limits. If you are over 150,000 miles, you can do the same, but better
yet, rebuild the engine now and install the gauge on the new one.
Happy motoring!
P.S.: I picked up the new engine yesterday, what a thing of beauty!
New everything for $2500. I also had Jerry install the 1.25 rockers
with swivel adjusters and do a three angle valve grind as per Robert
Lilly's recommendation, which is all I had time to do. Jerry also likes
these mods, he keeps these parts in stock and also has a three angle
valve machine in his shop.
--
Stuart MacMillan
Seattle
'84 Vanagon Westfalia w/2.1 engine
'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
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