The good news is that I started and drove my LBC yesterday for the first
time in nearly a year. It was running without oil pressure then, and
I've since pulled the engine and had it rebuilt. The bad news is that I
won't be driving it again any time soon.
The car is a red '72 TR6. This engine rebuild was supposed to be the
start of a new life for the car. I've rebuilt all the suspension and
the dash, plus other assorted odds and ends, since I bought it 6 years
ago. The funny thing is that everything worked when I bought it. But
just barely, I guess, because about everything that can break has since
then. Up until last year, though, I had had a fairly good balance
between time spent driving and time spend repairing the car. When the
oil pressure suddenly began to drop one blazing hot day last summer,
though, I knew I was in for a substantial investment of time and money
to get the car running right again.
Although I don't have a lot of practical experience, I've been a car nut
since I was a kid. Since I bought the TR6, I've planned to modify it to
run faster. Over the years since I bought it, I've accumulated a fast
road cam, a set of triple Weber side drafts, a hot ignition setup, and a
header. I went ahead and installed the header and ignition components
to get what benefit I could from them, but I knew the real performance
increase would have to come from the cam and higher compression, which
I could then enhance with the Webers. So I took the engine to a
reputable machine shop locally and had the following work done:
Deck block
hone cylinders (virtually no wear after 130K miles!)
machine crank .02 (?) under
restore rods & pistons
2 new valves, & all new guides
mill head from 7.75:1 to 9.5:1 compression
install Kent TH2 (Fast Road) cam
all new lifters
lighten flywheel (-5 pounds)
static balance whole engine to .5 gram, dynamic balance
The plan is to break in the motor with the stock ZS carbs, then rebuild
and re-curve the distributor for no vacuum advance and install the
Webers. I'll wait and see how my valve train performs under the
increased load and take corrective action later. It's all stock now, so
it'll certainly limit the performance gains I can achieve with the new
cam and carbs.
So this is where I was Sunday, after spending late nights the last
week and a half putting everything back together. I was very close to
finishing this past Thursday evening, and thought about trying to get it
running that night, but I had an opportunity to meet Scott Paisley, and
I decided I didn't want to pass up this first chance to meet another SOL
from the list. I'm glad I opted to meet him, because he suggested that
I see if the valve clearances specified for the new cam were different
from stock. I'd set the clearance to stock values, and sure enough, the
cam manufacturer called for significantly larger clearances. *Thanks,
Scott!* :^)
The First Problem: I got in a hurry and I did not baby my well worn
starter when I turned the motor over to build oil pressure.
Consequently I could not get it to start the motor. Although the motor
wasn't too hard to spin, it was very hard to start---my guess is that
new paint and liberal application of oil and sealers during re-assembly
made the ground path for the ignition system flaky. After numerous
attempts at refining timing and dwell settings, draining and recharging
the battery 3 or 4 times, and really grinding my starter much too hard,
I got the next-door neighbor to tow me behind his truck. He towed me
with the car in gear and the clutch engaged, and it started in about 15
feet.
The Second Problem: The car runs rough. I fiddled with timing and the
idle set screws, trying to get the car to idle well, but I couldn't get
it to run below 1400 RPM. It's rough at all speeds. I assume that the
fuel mixture is very wrong for the new cam and compression. Any guesses
as to whether it's too lean or rich? From the sound of the exhaust, I
guessed lean, but I could smell unburned gas and after running for about
45 minutes the exhaust pipe looked more black (thought not all that
noticeably) than grey to me. The stock ZS carbs are of the sealed-jet
type, but I have an older set of ZSs that I'll rebuild and try next.
But the car was running! Once I was satisfied that the idle was stable,
even though high, I drove it around the block a few times. Torque was
good! It pulled well at all speeds. I didn't take it above 3K RPM, but
that's all I needed for normal acceleration around town. Throttle
response was slow---I think the timing is somewhat retarted and the
vacuum advance tube is probably not sealing well at either end. The
suspension is firmer than I remembered. The temperature and fuel gauges
still don't work, after cleaning up the ground connections that I could
find. But it felt plenty warm.
I'd used some strong detergent to wipe oil off the body when I was
through putting things together, so I decided to wash that off before I
parked the car to collect my thoughts and start planning. As I
finished, a neighbor walked by. This is a significant neighbor, as his
recent work in refreshing his Alfa-Romeo significantly boosted my own
motivation in getting my car running. I got a huge grin and thumbs up
from Jeff, and I offered him a ride.
The Third Problem, Followed in Rapid Succession by the Fourth: Jeff
was sitting precariously on the rear deck (no time to install the
passenger seat yet), so I short-shifted my way to third gear as we
started off. But I heard something I didn't like, so I stretched it out
a little after we stopped and made a left. There it was. A definite
grinding, shrieking whine in second (but only second) gear. Another
stop and another left turn. Short shift to third, and a thumping
started somewhere in the back. Another stop and another left turn.
We're headed for home, here. But not before the thumping gets
persistent, and then insistent, and then, damn, there's something way
wrong back there! Apparently a universal joint (with no more than 3K
miles on it) is going bad on the right-rear half-shaft.
It's worth mentioning here that these problems were entirely unexpected!
This car ran *great* when I parked it. Despite the warn main bearings,
I'd gotten the car tuned pretty well, and it was strong and responsive.
The fresh motor was going to be a huge step forward with no looking
back. And in case it isn't apparent, I've spent a little money on this
car! I'll keep my whining to a minimum, but Folks, I'm unhappy!
I didn't have the heart to pull the plugs or look around at the drive
train last night when things cooled off, so I'm not sure where I sit
right now. But I'll certainly need to have the transmission thoroughly
rebuilt now. I'll have to have the starter rebuilt. And, depending on
what I find wrong with the half-shaft, I may wind up going back through
all the U-joints to see if the problem is epidemic---since I replaced
them all myself, I may have made the same mistake on all of them.
I'd appreciate any advice on tuning the new motor, reputable
transmission and electrical repair shops in Northern Alabama, and
initial setup for the Weber carbs. They're 40 DCOEs, which is about all
I know about them so far---can any of you suggest a good set of jets,
chokes, and emulsion tubes to start with? (MJB, I've heard that you're
an expert and that you sell Weber parts---I haven't given you my credit
card number yet, but this is an open invitation to give me your pitch!)
Kevin Riggs
(205) 730-3074
work@riggs.b30.ingr.com
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