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First published 22 February
1996
alfa romeo
spares
Valve trouble, Livia, ATE
or Garonne? Oh yea, spark plugs too and crank nut!
NGK B7ES spark plugs
The Golden Lodge 2HL is a great spark plug.
However, During the last years I have been using the NGK sparks. Be
careful so you get the correct plug for your 105 engine. I use B7ES
and not the BP7ES. The "P" indicates that the electrode is
a bit further down on the spark plug. The NGK refer to this as
"projected insulator". The B7ES have the correct
temperature and the electrode is not causing picking and maybe
causing other ignition problems.
The first letter "B" means the threading. In Europe
"B" means 14mm thread (M14 x 1.25). The letter
"E" means the length of the threading, in this case 19 mm.
The shorter threading has "H" as an indicator, = 12.7 mm.
The "7" tells us about the temperature of the spark plug.
"P" means "projected insulator". The
"S" is just for information about the material in the
plug. NGK has this S to tell that there is a copper in the core of
the plug. If I understand the NGK information correct, driving with
a "P" spark plug might give you trouble with pinking or
what ever you call it over there.
The best way to take the crank front pulley nut
off:
Put an impact socket of appropriate size over the nut, if you have
an AC car you may have to grind the O.D. of the socket to get it to
fit inside the pulley. Use a 1/2 drive breaker bar with the socket.
Turn the breaker bar/engine all the way over to the driver's side
and rest the breaker bar on the inner fender, put rags under the end
of the bar. Disable the fuel pump (pull fuse or disconnect relay) go
in the cockpit and hit the starter. This will spin that nut right
off!
Engine overhaul
When
lifting the engine, please note that the engine is leaning to the
left. This is my Spider with the head off. The cam chain is secured
by a wire and the support for the carburetors is still there. It's
OK to adjust the valve clearance with the head off.
Since my Spider is a 1967 with floor-mounted pedals, the servo
booster is what you see far right, green dot. You may also notice,
that the liners have been removed, dots and so has the battery, blue
dot. The red dot is the oil filter support. No spin-on filters 1967.
Head
Clean the alloy head, but watch out for sharp tools. It's easily
damaged when treated hard. This is the 1967 model up side down.
Check the valve clearance. If incorrect, you may use any shim from
an Alfa. They will fit any Alfa engine between 1965 to the 1990 I
believe. Never throw away a shim, it might turn out to be useful
later. I have noticed that Alfas hardly burn valves. The reason
might be the fact that they are sodium cooled. The exhaust valves
have natrium and sodium inside, so never ever try to brake one. This
might be dangerous if the sodium is in contact with water or any
other liquid or even air.
Twincam
The twin overhead camshafts act directly on the valves. Thus high
revs are no problem, no pushrods or rocker arms there, no, no.
I have however had some trouble with oil consumption due to old
engines. The engines pre 1970 approx. had no seal on the exhaust
valve guides, only on the intake guides. With new guides with seals
on the exhaust side too, the oil consumption goes down so check your
engines. My real nightmare was my Alfa 75 who was drinking oil like
hell. I overhauled the engine three times, liners rings, valve
guides and all. The combustion chambers were all clean and nice
every time I dismantled the engine. However, it turned out to be the
head.
There was this little leak in the exhaust hole on cylinder #3.
The hole expanded when hot and the oil was disappearing and my money
too. A new head solved that problem.
Pistons and rings and liners!
I have made rebuilds on some pre 1972 1750 engines. This is what
I always do: Step one is to certify that the pistons are the
problem. Have the compression ratio checked when the engine is hot.
The ratio should be the same on all four cylinders.
Pour some engine oil in the spark plug hole and check the
compression ratio again. If the ratio is increasing, the rings may
be leaking. If the ratio is almost the same, the valves and the head
need attention Remove the head and the sump.
No need to remove the engine for this kind of operation. Place a
hydraulic jack and use a piece of wood under the oil sump so you do
not damage the alloy fins. Loosen the engine supports. Raise the
entire engine as much as possible. Normally it's enough when the
gearbox hits the body, so you may place something between the engine
supports and the engine bay. The dots on the photo show how I do it.
The green dot shows the oil filter support.
Then raise the entire car and use supporting jacks for safety.
Never ever work under the car if it's not secured by jacks. If you
haven't already drained the engine oil, this is the time to do so.
Otherwise you will need to wash your hair in kerosene. Undo the
bolts and nuts securing the sump to the engine block. Gently draw
the sump forward to get access to the crankshaft.
From underneath the engine, remove the bearing caps and mark
them. They are already stamped with the number of the cylinder, but
just to be sure ... Start with the bearing caps on the second and
third cylinders. They are at their bottom dead point if you have
done the right thing. Slowly turn the crankshaft 180 degrees until
the first and fourth bearing cap is at their bottom dead point and
remove these too. On the Alfetta and 75/Milano overhauling is even
more easy. Just raise the car and remove the sump. Note the spin-on
filter, yellow dot.
Sump removed, Milano-engine
Be
careful so you do not damage the bearing surfaces of the crank-shaft
and gently press the pistons upwards. Cover the crank-shaft bearings
one by one while working. Mark the pistons so
you know which is # one etc. Check if the pistons are of the offset
kind. If so, there is an arrow on top of the piston. The arrow shows
the direction from intake to exhaust, so be careful not to turn it
the opposite way. If your engine is so old that it has the non
offset pistons, I would replace them with newer ones. The Alfetta
1,8 pistons are excellent and easy to find. Both liners and pistons
will fit your engine like new. The next photo shows the Milano
engine with the liners removed, dots. As usual, the engine is still
in the bay.
Milano engine, liners removed
Be
careful not to damage the surface when you remove and change the
rings. There are several tools for this purpose, but you own hands
might be OK too. The rings are marked "TOP" etc. Have a
look in a workshop manual if in doubt. Remember to keep the openings
of the rings away from each other, i.e. 120 degrees. To remove the
liners you may try just to press and draw them upwards. There are
special tools for this purpose, however some are expensive. I use an
old piston with the top ring on. Put it up side down in the liner
until the top ring is expanding and then use a soft hammer and a
piece of wood to remove them both. Remember to use an old piston,
not the new one. The next photo might give you the idea.
Liner in block
Inspect the liners for
scratches etc. Replace all if necessary. Use your fingertips to
check them.
- Clean the bottom of the liners as well as the engine block,
but remember the bearings!
- Replace the O-rings with new ones. Do not use more than one
per liner though.
- There are steel shims available for diesel engines if your
liners are too short. Once, I used a set from an IVECO diesel
engine. That car is still running, BTW.
- The liners normally do not need any sealant, but since it is
not that fun to open the engine again if it is leaking, I use a
little bit of sealant. It is very important to keep the engine
absolutely clean.
- Check that the liners are about 0,05 mm higher than the engine
block, every one of them. This is what I have learned the hard
way, believe me. Have a look in the Alfa Owners Bible or any
workshop manual.
- I do the operation with the engine in the bay, it is not that
tricky.
- Finally, have the head overhauled at the same time. Valves,
guides etc. may need some attention too.
Clean the pistons. Then take them to your local grocery shop
and check their weight one by one. Unless you have a
weighing-machine of your own.
There should not be any difference between them. If so, see
your local Alfa Service station.
If you have any comments, please send an E-mail
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