On Sep 20, 8:43?am, Andy <andrewcjoi....RemoveThis@yahoo.com> wrote:
> My question is, what is involved in swapping the engine? Would this
> job require a lift or any special tools or techniques that an ordinary
> tinkerer like myself would not have? I need to decide if I am going to
> attempt the job myself, pay someone to do it, or just sell the bike as
> a fixer-upper and forget about it.
Removing and replacing an engine may seem like open heart surgery,
but, if you take your time and make notes and keep all the different
hardware segregated in separate boxes, you won't have a dead patient
on your operating table when you're finished.
Got some good quality metric combination box/open end wrenches and a
few good quality allen wrenches?
6mm, 8 mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm and 17mm are commonly
used box/open wrenches. Honda tends to use smaller bolts with uneven
size heads.
5mm, 6mm, and 8mm allen wrenches will come in handy. Hardened steel
allen wrenches are black, not chromed.
A good quality #2 phillips screwdriver will be necessary.
Gather several cardboard boxes to store parts in as you remove them.
You can put the nuts and bolts into plastic containers.
You can make a sturdy engine work box out of scrap lumber with the aid
of a saw and a hammer and some nails. It's nice to have some old
pieces of carpet to lay on the cement floor, if you're going to be
laying the engine on the cement instead.
The seat is the first thing that has to be removed and the last thing
to be reinstalled. Stash it out of the way.
Carefully remove the plastic side covers, and store them in a box.
Disconnect the battery and its vent hose. You'll probably want to
remove the battery and set it aside if you're going to lay the bike on
its side to remove the engine.
If you have an automatic vacuum operated petcock, you won't need to
drain the gas tank unless the petcock leaks.
Disconnect the fuel line and vacuum hose and any air vent hose and
electrical wires coming from the gas tank.
There are probably two bolts holding the gas tank down at the rear.
Slide the tank backwards and set it aside in a cardboard box so it
won't get scratched.
The spark plug cables have to be disconnected and tied up out of the
way and the crankcase ventilation hose has to be disconnected.
The clamps holding the carburetors to their rubber hoses have to be
loosened up so the carbs can be worked loose from the rubber hoses.
You might have to remove the airbox lid and remove the air filter and
set it aside so you can slide some of the rubber carburetor hoses back
into the airbox to make room to remove the carbs.
If you have to remove the airbox, some air boxes are a challenging
puzzle to wiggle out of the frame. Stash the airbox in a cardboard box
with whatever hoses and hardware was associated with it.
You might have to spray the carburetor mounting hoses with aerosol
carburetor cleaner to soften them enough to work the carbs loose.
Some people say that hot water works to soften the hoses. You can
probably connect a garden hose to your water heater if you decide to
go the wet route.
You will have to disconnect the choke cable if it goes up to the
handlebar. If the "choke" is just a knob on the side of the carbs,
leave it alone.
You will have to de-adjust the throttle cable barrels to get enough
slack to disconnect the cables from the carbs.
If there is a gawd damned charcoal canister on top of the engine
crankcase at the rear, that thing will have to be disconnected from
the carbs and stashed in its own box. There is probably a decal under
the seat or on top of the air box to show how to reconnect the rubber
hose octopus associated with the canister.
Look for color coded tape on the hoses or painted dots of different
colors.
Once you have worked the carbs loose, pull the whole bank of four
carbs out to the right hand side of the engine and turn the throttle
quadrant between the #3 and #4 carbs so you can disconnect the ends of
the cables from the keyhole slots they are in.
Pay attention to how the throttle cables connect to the carbs, you're
going to have to reconnect them and rig out the throttle cable tension
after you reinstall the carbs.
Set the carbs aside in a box with all the associated clamps and hoses
that you've removed.
You'll need to disconnect the starter cable from the starter and the
ground cable that goes from the frame to the crankcase.
You will have to remove the exhaust system and you can get into
problems when you loosen the bolts holding the exhaust pipes to the
head.
If you strip out a bolt hole or break an exhaust pipe bolt, you'll be
unhappy.
I recommend spraying the bolts with penetrating oil and and smacking
the heads of the bolts lightly with a hammer and drift to set up a
vibration to get the oil to penetrate if you don't have an air impact
wrench available.
Hang the exhaust pipes and mufflers up so they are out of your way.
Watch for exhaust gaskets stuck up in the exhaust ports, you'll want
to re-use them if they aren't damaged.
The clutch cable has to be disconnected if it's a cable type, or, if
the clutch is hydraulic, you can remove the slave cylinder from the
side cover and tie it up out of the way.
You'll have to remove the front sprocket cover to get at the front
sprocket.
You'll have to loosen the rear axle with the tool in the motorcycle
tool kit and de-adjust the drive chain tensioners so you can at least
slip the drive chain forward off the countershaft sprocket.
If you have an endless chain, you will probably just leave it on the
swing arm, but if you have a clip type master link, you might want to
remove the master link and the chain and stash the chain in a box.
You'll have to disconnect the alternator stator connector and the
pulser coil connector.
If I haven't forgotten anything, you are now ready to loosen up and
remove the engine mount bolts preparatory to laying the bike on its
side and maneuvering the engine onto its right hand side, sitting on a
sturdy wooden box.
That's right, Andy, you've torn your Honda to flinders and you're not
even half done.
With the engine out of the frame, you can pick up the chassis and roll
it away from the engine and then maneuver the old engine onto some
kind of low dolly so you can roll it away to make room for your "new"
engine.
I use a hack saw to cut the basket off an old shopping cart to make
engine dollies.
Good luck, and don't worry, be happy.
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