Many thanks to all who replied; I'll reply to some specifics, beginning
with Matt's suggestion:
~ Using your "dingle-ball" hone, as mechanics refer to them, (if you
~ decided to yank the engine) would not be a bad idea.
I'll probably do that; this motor doesn't have much time on it and
I can still see the machining marks from when Kaeding bored it to
fit these pistons, but the hone seems like a reasonable thing to do.
~ ( I mentioned removing the engine while using the hone because if you
~ lose a "dingle-ball" and its lodges in the block you are out of luck.
~ Also, a good cleansing with brake cleaner or contact cleaner in the
~ bores is much easier on an engine stand out of the car.)
I've been talked out of doing it in the car. It seems like so much
more pain and in particular so much more stress for me to leave it
in the car. I have a good engine stand and come-along in the garage;
I won't have to rent the cherry-picker till it's time to reinstall it.
~ Also, I have mentione it before but I'll say it again. . . With the
~ bottom and top end out, check over the mains with a "plastiguage" tool
We did that last summer when I refreshed the rod bearings. Rods and
mains alike were right at the tightest allowable spec in the manual.
The mains were solid and shiny, the rods had some wear on the bearing
inserts so I replaced them. At that time the engine had only something
like four race weekends on it; I've added maybe 350 miles of street
driving since then.
~ and check the rocker arms for play.
Thanks for reminding me; I've got the usual rocker-arm wear indicator,
the pressure-gauge wobble at hot idle. I'll probably just do it the
easy way and buy a whole new shaft/arm assembly.
~ Also, USE LIBERAL AMOUNTS, of
~ assemble lube on rod bearings, etc. when reassembling your engine.
Indeed. We did this both when I built the motor in the first place
back in 1991 and also when Chris and I refreshed the rod bearings
last summer. RedLine's assembly lube was the easiest to use, smearing
on nicely and staying in place.
~ One
~ gentleman's idea of replacing the oil pump is excellent (many mechanics
~ will not do even a semi-rebuild such as yours without replacement of
~ this vital, often neglected part.)
I put in a new oil pump when the motor was apart last summer.
~ When you remove the engine and
~ transmission as a unit they install very nicely and you can degrease
~ the entire lot and check for bad or worn motor and tranny mounts.
Hmmm. That's a possibility I hadn't considered. I hate pulling the
transmission, but it's absolutely filthy from the old motor's leaks
over many years.
~ (With the new found power this will put a "tweak" on those things.)
~ P.S. Sometimes pulling out the pistions "through the top" can't be
~ done without a ridge reamer. Don't start the job without access to one
~ of these.
No ridges. Maybe you joined late; this motor is relatively fresh (see
above), it's simply lost a piston because the idiot driver ran it on
pump gas with too much compression.
Some other replies:
Ted Jerome said:
I've had some of my best naps under my Elan on hot summer days!
:-)
Well, I'd crawl under an Elan; if it falls on you, the worst thing
you have to worry about is the fiberglass dust getting into your
lungs. :-) But this is a big, heavy MGB we're talking about...
Randy Wilson says:
Besides the fore-mentioned dripping and bolts, you have to
deal with things like scraping pan gasket pieces and torquing bearing caps
upside down on your back.
That's the deciding factor for me. I don't want to worry about whether
or not I really got those big ends tight after this goes back together,
and I'd much rather turn the motor upside-down on the stand and simply
lay the pan gasket (suitably Permatexed, of course) on the block before
zipping on the pan bolts.
BTW, one trick I noticed with the oil pan was that you want to make
sure you get all the old gasket off, and then you also want to make
sure that any high spots from overtorquing the pan bolts are flat.
I came up with a really great way of doing that, if I can remember:
a block of wood under the edge of the pan, then tap down on the top
using a 3/8" drive extension as the "drift." The rounded part of the
3/8" extension is almost exactly the right size to flatten out the
raised parts of the pan. This is critical to reducing (notice I
didn't say avoiding :-) leaks when you reassemble.
Oh, and good point about the clutch; that of course was the worst
part of reassembly, wiggling the motor (it's damned hard to wiggle
a 500-pound lump of iron) to get the splines to line up. Since this
clutch has been engaged and disengaged a few hundred times since I
put it in last winter, it should just slip into place.
Thanks for hearing me out. I'll keep everyone posted as to my progress
and to whatever else I uncover while it's apart. Besides, Kim really
wants to be involved with this, and I think it'll be a lot easier for
her to work on it (cleaning the bores, etc.) if it's on the stand.
--Scott
In short, the motor comes out so I can do it right. That's the whole
lesson that this car has been teaching me, that unless you do it the
right way the first time you have to redo it later.
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