Date: Wed, 26 Jul 1995 20:36:24 -0700
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: eugp@uclink3.berkeley.edu (Eugene C. Palmer)
Subject: Engine Log
Maniacs,
wOw, things just keep popping up here in exotic, erotic, excessive, engine
world. Latest developments;
After pulling the heads and cleaning/staring at the short block, P/C set,
etc., for several days, I've finally found the major problem. Sooo, GB309
cam, dual springs, all superbly lubed with my cool pre-oiler. NOT. Even
though I had the engine _up to pressure_ on the stand with a drill, in the
car without rockers or plugs, then again with rockers, then again with
plugs, apparently that is not enough to be _sure_ that a new aftermarket cam
is work-hardened on start-up. Noooooooo, you _must_ run it in at 2500 rpm
for better then 5 minutes, have some STP, or synth grease on the lifter
faces and cam lobes, OR ELSE..........!!!
Intake lobe for 1 & 3 is not a lobe anymore, it is a circle. Exhaust lobe
for 1 & 3 is barely a lobe at all. Both intake and exhaust for 2 & 4 are
just dandy, thank you. This after only 2000 miles, wOw. All the lifters
look evil, with pitting on each one. Guess this explains why the car felt
like it was running on two cylinders (it was), and that the compression was
down, (hard to believe there was any at all), and that # 1 & 3 stopped
firing. Guess I'm starting this engine over alltogether.
About the only thing I feel good about is that I caught it at all. The
reason I caught it is the Oberg filter light came on, and the fact that the
engine failed. But at least it didn't wreck the heads, p/c kit, crank, and
case in the process. Though I cleaned the filter after less than 500 miles,
I never realized how serious the situation was. All the particles from this
trauma were very small and I thought were within the limits of a break-in
period...NOT.
When I first started this engine, it would barely start, due to inadequate
fuel maps. When I did change the maps and it started, I stopped it after a
couple minutes to check on oil leaks etc. Noooooo, your NOT allowed to stop
a new cam when it starts up, you _must_ keep it running at better than 2500
rpm for 5 minutes or more to harden the cam.
Plus, I have a sneaking suspicion that I am not getting enough oil spill-off
from the rods. When I re-assemble, I am going to add some grooves to the
sides of the rods.
I think there are three reasons the cam failed here. 1; the start-up was
bad, not enough pre-lube on the lobes and lifters, 2; not enough oil
spill-off from the rod bearings, 3; manufacturing defect on the cam, weaky
material (why else would 2&4 be fine, but 1&3 fail?)
Presently I am putting together the order for new a cam, lifters, bearings,
gaskets, cylinders honed, etc. I am also going over my old war horse engine
so I can install it and drive the car while I fool with the exotic, erotic
stuper-engine.
Later,
Eug,
'71
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