And
the beat goes on….
I
was called by the owner, described above, in early Dec. to see if I
could help him with repairs to the CB77. He had sold both the 1963
CB77 and a 1966 CL77 to the same owner in nearby Rancho Santa Fe. He
sent photos of a large pool of oil beneath the CB77 and maybe a
little leak beneath the CL77. The new owner was requesting assistance
in getting the oil leaks repaired as soon as possible.
I
was going to be in the general location (about 40 miles from home)
for my monthly chiropractor visit, so it was convenient to swing by
and have a look. It wasn’t pretty….
I
had never seen that kind of oil leak beneath any 250-305 before,
unless the drain plug was loose and the bike sitting for weeks. I had
brought tools and the previous owner supplied some oil seal kits so I
could hopefully do an on-site repair and head on home. After a quick
view, it was obvious that the bikes needed to come back home with me
for repairs. The new owner had left the key in the PARK position, so
the battery was completely dead.
The oil leak was drooling from the
shift shaft seal, which is an easy replacement, but the oil smelled
of gasoline which apparently leaked into the crankcase before the
last ride. Somehow, the gas-oil mixture didn’t ignite when the bike
was operated and then shut down. The diluted oil leaked past what was
probably the original 60-year-old seal and drained the crankcase
down to where the level was nearly at the seal level in the clutch
cover. Thus the large pool of oil beneath the bike.
Both
bikes were loaded up into the Tacoma and hauled back to Rancho de
Honda for repairs. The next day I changed out the shift shaft seal,
then drained the oil as the drain plug appeared not to have a gasket
installed. What drained out was watery, dark-colored oil that reeked
of gasoline. I had also replaced the crankshaft seal and was putting
things back together when I turned the engine over with a wrench and
heard a god-awful squealing sound emanating from the engine
somewhere up high. It was one of those fingernails on the chalkboard
kinds of noises, which got louder when the spark plugs were removed.
My best guess was that the diluted oil had caused some kind of
metal-to-metal damage and that the engine would need to be removed
for inspection and repairs. After the findings were relayed to the
owner, permission was granted to move on to the repairs.
I
did pull the clutch cover off, just in case the primary chain nut was
backing off or something else was loose under the cover. I did find
the oil filter was tight on the shaft and that the outer clutch
pressure plate was contacting the inside of the clutch cover, too.
The filter needed servicing anyway. Clearance was provided so it spun
easily on the shaft as normal.
Once
the engine was out, the top cover was removed and the crankshaft was
turned again to try to pinpoint the squealing noises. The top end
looked pretty dry, but nothing horrible stood out. I shot some WD40
into the cam bearings, where I thought the noise might be coming
from, but it didn’t have any effect.
The
cylinder head was then removed and the noise became centered on the
pistons and rings. The cylinder walls were dry and the rings were
dragging against the cylinder walls metal-to-metal. I suppose that if
I had just shot some oil down the spark plug holes when it was still
assembled, the noise would have been reduced and that would have
pinpointed the cause of the noises. Still, there was evidence of the
head gasket leaking up front and around the edges, so it was best to
just go through the top end anyway.
The
speedometer was showing less than 9k miles and the relative lack of
carbon buildup on the piston crowns and valves seemed to reinforce
the truth of the miles shown. The ring gaps were not terribly
excessive, but the to edges of the rings were worn sharp and several
of the rings were sticking in the ring lands of the pistons. The
pistons were free to swing back and forth on the rod ends, but the
piston pins, themselves were immobile when the clips were removed.
Again, I give thanks for finding the Benelli piston pin removal tool
that I had bought a few years back when I owned a Benelli Sei. Using
the tool to its fullest the pins begrudgingly gave way to the tool’s
force and were removed. One pin had an odd wear spot on the middle of
the pin, but mostly they were undamaged. Piston pin fit is normally a
finger push fit into the piston pin bores, so it is unclear why these
had become so tight. I have a bottle brush hone that is the right
side to open up the pin bore holes and it was used to allow a proper
pin fit.
I
had the cylinders honed at my local machine shop and ordered new STD
piston rings from who turned out to be a former San Diego friend who
moved to Minnesota a few years ago. While waiting for the parts, I
disassembled the cylinder head, checked for any damage, touched up
the exhaust valve seats, and reassembled it all.
When
I turned to the round bowl carburetors, I discovered that someone had
sealed up the overflow tube on one float bowl and that the main jets
were #125 instead of #135 specified. The float levels were set at
26mm instead of 22.5mm so perhaps the bike had lived in high altitude
for part of its life. The carb insulators were RTV glued onto the
carburetor flanges and cylinder head. The more you look the more
things wrong you find, in many projects like this.
The
float bowl overflow tube had a split down the side causing a fuel
leak, which was soldered for repair. The floats were original round
bowl types, which come close to the side walls of the float bowl. I
had many leftover round bowl gaskets from kits which contained both
round and square bowl gaskets. Sadly, most of them had come from
Keyster kits and they are just not made correctly to OEM specs. When
the bowls were removed, the gaskets were cork and had shrunk up quite
a bit. I ordered new floats from 4int1.com along with their
swell-proof gaskets.

I
had already removed the clutch cover, so I thought I better check the
clutch plates. They were, of course previously stuck and there was
rust embedded into the steel plates. Oddly, the outer pressure plate
edges were sticking up proud of the edges of the clutch basket,
instead of just tucked under the edges. This stack height apparently
led to the contact marks inside the clutch cover. All the plates
seemed to be of the right thickness and number (it was a 6-plate
clutch), so I decided to mix-match the clutch pack with some thicker
268-020 plates, just fewer of them. In the end, it was a little
shorter than normal, but it will clear the clutch cover now. We’ll
see how that works out in the end…
I
cleaned the carb insulators of the black RTV that was coated over
them and installed new Honda 260 code o-rings on the insulators and
the carburetor flanges. The cleaning process always involves
flattening out the flanges, changing the o-rings, and checking for any
tendencies for the slides to stick in the carb body bores. The main
jets will be bumped up to #140s, which seem to work better on today’s
E10 gasoline, which causes engines to run lean on standard settings.
When
the engine was installed, I tried to quick-fire it up, but it
backfired and spit back. The coils were tightly grouped together and
the leads crossed each other. Swapping them back got an initial
startup, but the ignition timing was incorrect. When the right side
points were adjusted, one of the point screws was stripped in the
hole, so a substitute point plate was acquired and installed. After
picking up a fresh set of D8HA NGK plugs and raising the needles up a
notch, the bike finally fired up and settled down to an idle. The
throttle cable was a bit cranky and the cable adjuster on the right
side carb is raised up more than the left to get them synchronized.
The
last step will be to replace the old floats with the square bowl
types that have more clearance around the edges, so they don’t
interfere with the float bowl gaskets. Of course, the petcock needed
to be rebuilt including the brass tube that was down to about an inch
high.
On
top of it all, the tires are old and the drive chain needed to be
replaced. I did find an inexpensive new 530 pitch drive chain and
installed it before placing the kickstarter cover back on the engine.
Setting the clutch adjuster with the new clutch pack setup actually
caused the alignment marks to be just about right. The tire pressures
were 18/12 psi when I took it around the block, very slowly.
The
co-conspirator….1966 CL77
This
bike came down with the 1963 CB77 for a checkover and a small oil leak
complaint. It was parked next to the CB77 in the garage, adjacent to
the large pool of oil/gas on the floor. I had gone through the bike
earlier in the year after it had been sitting for about 10 years. It
required the usual fuel system clean-out, a new battery and, and
overall tune-up procedures.
I
had ordered a pair of the pushrod seal retainer kits from the
Cappellini dealer on eBay. The first one went on the CB77 after the
extensive rebuild. This second one should have been a 15-minute parts
swap but turned into over an hour due to discoveries beneath the
kickstarter cover.
First,
the two 6mm counter shaft plate screws came out very hard, perhaps
installed with Loc-Tite. After I removed the screws, I wanted to
clean up the threads for the new retainer screws. The 6mm tap went in
about half-way on both sides, then sheared off when I was trying to
get that little bit of extra thread clean-up. There’s no getting
broken off taps out of a hole like this, apart from an EDM machine.
Fortunately, I had a spare shallow spline sprocket that was in decent
shape. So, that problem was solved. HOWEVER….

When
the sprocket was pulled from the countershaft, I was amazed and
horrified to see that the countershaft seal was partially hanging out
with a large open gap between the engine case and the edge of the
seal. It had been installed with some of the Permatex Moto-Seal or
Honda-bond liquid sealer when the engine cases were bolted back
together again. Whoever did it, failed to notice that the seal had
squeezed out at an angle and was left in that condition. Not only
that, behind the rotor there was JB Weld, right where the engine
cases get damaged from failing to locate the crankshaft main bearing
in the knock pin correctly.
It’s
hard to know if the damage was done before the last engine work or
during the assembly of it. The possibilities are that the bearing was
reset and the oil hole was not blocked. The other scenario is that the
bearing was left in the out-of-indexed location, which blocks the oil
flow to the crankshaft bearing. The builder might have noticed the
cracked engine case and just sealed it up, rather than dive back in
to reset the bearing properly.
The
bike has straight CL72 exhaust pipes with the Snuff-or-Nots installed
at the back. They knock down the noise a little bit but I’m sure
that the neighbors would prefer that I not run the bike around for
long. The bike repair work was done, but was waiting for the return
of the speedometer repairs from Foreign Speedo in San Diego, my go-to
guy for vintage Honda speedometer repairs.
When
the bike was ridden the speedometer needle was whipping around and
scratched the faceplate. Fortunately, Foreign Speedo has a guy in San
Diego who can silk-screen the faces back to their original condition, so
there is a time lag when he comes to pick up various faceplates and
when they are returned. The bike runs out very strong (and loud), so
the speedometer is all that is needed to return it to service.
The bikes are scheduled to be returned on Dec. 28 in much better condition than when they left the owner's garage.
Just another few weeks in the life of MrHonda...
Bill Silver
12/23