Gege Blog 7.1 Dismantling engine B (f) .pdf



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Gege Blog English – 7.1 - DISMANTLING ENGINE B – Demontage moteur B
Monday 17 December 2012

5H
P

We had already dismantled the distribution cover and the magneto gears to send them to Michel in Italy, the A-engine gears
being irrecoverable: ( See copy of Chapter 6.16 - MAGNETO SPROCKETS - Pignons d'entraînement de la magnéto …. At the end
of this document )

IC
AL
E

Michel has now asked for the oil pump of engine B in order to compare its flow rate with that of engine A which he has
repaired. While we're at it, we'll take the opportunity to completely dismantle this engine. Since it has been marinized, we
expect to encounter (even) more difficulties than with engine A, and our fears are not unfounded ...

The disassembly order is sometimes a bit different, more by obligation than by choice ...

M

Monday 14th January 2013

G

VG

/A

First thing, dismantle the timing gears.

And first surprise, we discover a screw at the end of the crankshaft. We take out the impact screwdriver, for nothing because
this screw is screwed in ... nothing! No thread in the crankshaft

5H
P

2

VG

/A

M

IC
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... But the centering hole seems to have been enlarged…

G

If we look carefully, we don't see the big cylindrical pin (which is used to drive the dynamo) through the hole, there are indeed
two half-pins well inserted, how to get them out ???? It looks like an infamous do-it-yourself of unscrupulous mechanics ...
(we'll see later that we misjudged the situation !)

...

5H
P

3

VG

/A

M

IC
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The extremities are well matted...

G

and it will probably be necessary to saw and drill through everything...

We remove the lubrication tube from the gears so that Michel can make a copy for the other engine.

4

IC
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5H
P

Attempt to extract the camshaft sprocket; the tripod extractor rips; let's reschedule.

G

VG

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M

Removing studs ( De-ginning ??? )

5

5H
P

We'll take out the oil pan. The holes are completely eccentric and the studs are bent!!! Bad machining after casting, and the
crankcase is crooked. Probably an afternoon job ! ( Monday job in Belgium )

VG

/A

M

IC
AL
E

We remove the oil plug, it still has its strainer, completely clogged by a filthy molasses. When you think that the oil suction

G

tube of the pump goes in there, you wonder what it could still suck !

The strainer with the troughs is indescribable, and to think that this engine was running like that!

5H
P

6

G

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M

IC
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Apart from the molasses, you can see the "jets" that feed the troughs, they are flush and all of the same diameter...

Sight of a connecting rod.

7

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5H
P

It flows well, fortunately in the basin

G

VG

/A

M

Extraction of the suction tube from the pump

, it is broken and completely blocked at the bottom

but not at the top.

,

IC
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E

5H
P

8

G

VG

/A

M

Extracting starter studs

Disassembling the clutch on the flywheel

It's coming ...

and it's out:

G

VG

/A

M

IC
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5H
P

9

5H
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10

The exhaust manifold is tired !

G

VG

/A

M

IC
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Now we have to remove the flywheel..

Unscrewing the big flywheel nut forces us to take out the big Facom wrench, and to knock on its end after having blocked the
crankshaft with a wooden block

5H
P

11

G

VG

/A

M

IC
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The rusted threads have to be re-threaded to be able to put the screws of the extractor

Thanks to this tool made by Michel, it comes out quite easily by pulling hard.

.
But the socket of the tool remains stuck on the end of the crankshaft; we will take it out later .
Tuesday, January 15, 2013

12

5H
P

There's a funny "thing" attached to the cylinder head!

G

The valve lifters are blocked by rust....

VG

/A

M

IC
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!

13

G

We take out the "crush washer"...

VG

/A

M

IC
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5H
P

We'll start today by taking out the oil pump. Unscrewing the cast iron cover.

… and remove the lid.

5H
P

14

G

VG

/A

M

IC
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Now we have to take out the two gears, the crankshaft one and the pump one (and the flywheel extractor bush stuck on the
crankshaft can be seen )

The sprockets are out, there's an incredible amount of backlash.

A small Dremel job on the pin locking the pinion on the pump

IC
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5H
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15

G

VG

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M

…and we take out the pin, first with a punch,

,

…then with a nail.

During handling, the water tube fell down, no wonder, the stud that holds it is reduced to a derisory section!

5H
P

16

G

VG

/A

M

IC
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The sprocket must now be extracted from the crankshaft; it is "simply" screwed on (with a right-hand pitch it tends to tighten
when the engine is turning).

On Michel's advice, we protect it with a metal strip cut out of a tin can of ... Jupiler beer

, but it slips

5H
P

17

G

VG

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M

IC
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.. We finally and painfully unscrew it after having removed the stud, and with a big plumber's pliers...

We take off the pump by sliding a knife between it and the crankshaft block,

IC
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5H
P

18

.

Done!

G

VG

/A

M

but we have to unscrew studs to get it out. .

19

.

G

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M

IC
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The two rear crankshaft bearings seem to be in good condition

5H
P

Scratching of the locking screw of the outer bearing, which had disappeared under the dirt .

, one of the grooves is "homemade", strange! . They are different from the A-motor, the bearings have probably been
replaced.

5H
P

20

G

VG

/A

M

IC
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We then hoist the motor on the workbench so that we can work without breaking our backs...

Easier removal of the sprocket on the camshaft (don't forget to check the punch marks)

G

There is an adjusting washer

VG

/A

M

IC
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5H
P

21

The camshaft adjustment bearing is well wedged in the block ...

5H
P

22

G

VG

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M

IC
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Remove the retaining flanges of the valve tappet brackets

… and remove the 2 nuts securing the cast iron cylinder block to the aluminium crankcase on the tappet side ;
there are still 2 more 17 mm nuts on the other side.

Remove the spark plugs; two have 3 electrodes!

5H
P

23

G

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M

IC
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I lift the cylinder block, it's not very light but the pistons remain stuck in the cylinders, especially one with a seized pin

In full effort! it would have been easier on the ground

André thinks it's not so heavy but the pistons are out !

5H
P

24

VG

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M

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The third piston is almost stuck on its pin...

G

Cylinders appear to be in acceptable condition

The small cylindrical pins holding the valves are pitted in their cups

5H
P

25

G

VG

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M

IC
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… and one cup has been replaced by a piece of crap. All this was ready to give way!

Remaining to be removed : the cylinder head (and it is not won!), the camshaft, the timing sprocket on the crankshaft, the
valve tappet supports

Friday, January 18, 2013

26
André is not available today, but I still want to finish dismantling the stubborn crankshaft! All parts are tightly tightened, unlike
the "A" engine, in this aluminium block.

IC
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E

5H
P

First the connecting rods, easy, although the nuts are very tight (much more than on the "A" engine). The spoons are in perfect
condition here, the bearings are not too marked but they should be measured and presented on the crankshaft when it will be
dismantled. On the other hand, the groove of the top ring is very wide on all pistons which, apart from that, are in good
condition. One drawback: the piston gudgeon pins have a lot of play, we will have to check if it is them or the pistons that are
at fault.

The connecting rods are marked 1 2 3 4 from front to rear by punches on the body and facing the cap.

G

VG

/A

M

I move on to the valve lifters, a lot of oxidation but I manage with a wrench to make them turn in their supports and to move
them up …

… and to release the camshaft. I push it from back to front, and the collar of the camshaft drives the front bearing.

5H
P

27

/A

M

IC
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The tappet supports are also blocked in the block, ( on engine "A" I had taken them out "by hand"! )

G

VG

By hitting very hard (so hard that I fear to crack the aluminium block) on a stub whose end has fortunately the diameter of the
pushers, I manage to take out the supports

28

5H
P

To take out the rear bearing of the camshaft, I put the camshaft upside down in the block, so I can take advantage of the front
flange to extract it, always by tapping (very) hard ...

G

I remove the camshaft for good,

VG

/A

M

IC
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E

...

29

5H
P

not too much play on its bearings, but it is quite corroded ...

...

VG

/A

M

IC
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The distribution sprocket on the crankshaft remains to be extracted, and first, its pin

G

I block the back of the crankshaft with a piece of wood in order not to leave it in overhang



30

5H
P

…and I arrive, always knocking very hard on my "widened" stub (on the right on the photo, another tool made there ... 30
years ago by Michel !) and then on a punch, to finally extract this cylindrical pin which…

VG

/A

M

IC
AL
E

..., contrary to what we thought, is indeed in one piece but has been drilled in the middle to place a screw intended to wedge
it

G

Thank you Michel, you were right, you're the best!

31

G

VG

/A

M

IC
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5H
P

All that remains is to extract the sprocket, but once again it requires the tripod Facom puller which is just getting enough
room.

32

5H
P

I remove the key,

/A

M

IC
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E

and then I just have to take the crankshaft out the back.

VG

.

G

It is quite strongly marked by oxidation on all the bearings, this will require a rectification (hence new bearings as well as those
of the connecting rods!), unless I find a new crankshaft, and provided that the bearings are in original dimension and not
ovalized ...

5H
P

33

/A

M

IC
AL
E

I remove the screw that holds the front bearing, but the bearing stubbornly refuses to come out !

VG

!

G

Locating (a bit late, but there is always a way out!) the marks on the timing gears . As on the "A" engine) they correspond to
the TDC compression of cylinder N° 4 (at the rear), valves closed.( Cylinder No. 1 (front) at TDC with valves rocking. )

So all that remains is to take out the bearing above , uncouple the pistons from the connecting rods and measure the whole
thing in order to know more or less what to expect when renovating this "B" engine. Do not forget to remove the cylinder
head from the cylinder block, and the exhaust manifold without breaking it!

But I stop here ; enough for today...

34
Saturday 19th January 2013
Today, I'm taking crankshaft measurements. In addition to the fact that it is oxidized, it is also more worn than the original "A"
engine,

IC
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E

5H
P

:

G

VG

/A

M

… but less striated (remember that the "A" engine got a new crankshaft, ( in dimension 35 for the connecting rod bearings and
32 and 33 for the crank bearings):

It's a pity, because here, and contrary to the "A" engine, the connecting rod bearings are in very good visual condition. Were
they changed without rectification of the crankshaft?

35

IC
AL
E

5H
P

Nevertheless, the connecting rods are showing a non-negligible angular displacement in the plane of the flat crankshaft,
whereas in the axis of the connecting rod the play is small. It is as if the bearings are bobbin shaped. You would need a bore
comparator to check, but I don't have one ... Or could it be that the crankshaft’s bearings are larger in the middle? I'm going to
re-measure them in several places...

G

VG

/A

M

Piston pins have a lot of play, one piston is cracked

, another one is slightly seized up, and the piston rings are loose in their grooves ...

36

IC
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5H
P

Michel has already made the tools to take out the cylinder head by pushing on the block through the spark plug wells !

Long (2h 33min 47s, but we didn't break our record ...) discussion with him on Skype tonight, to evaluate the next events for
the engines and boxes.

G

VG

/A

M

We take this opportunity to imagine a tool (made from this tool that he made for me in 2009 to extract the rocker arm rod
pushers of the 38 engine of my Traction Avant ) to extract the front bearing of the crankshaft :

37
Sunday, January 20, 2013

5H
P

So there you have it, Michel has not wasted his time

G

VG

/A

M

IC
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E

...

He even made corners of increasing thickness to insert between the block and the cylinder head; we're going to massacre the
gasket but it was planned!

38
Tuesday 22nd January 2013
While waiting for the new tools, André made a suggestion: the connecting rod bearings of the B engine are not bad, and the
crankshaft of the A engine is not very worn. Why not try to put them together?

.

G

VG

/A

M

IC
AL
E

5H
P

So I mount the B rods on the original crankshaft A, and as I expected, the rods are well blocked:

They have probably been fitted with new bearings slightly thicker than the nominal dimension of 35, to fit on the worn B
crankshaft. The crankshaft A being less worn, tightens ...It would be enough to measure exactly the inside diameter of the
bearings (hoping that they are not ovalized, and this requires a bore comparator that we do not have), and to grind crankshaft
A accordingly, which will have the added advantage of removing the grooves ... And if there is enough material, we could even
consider grinding crankshaft bearings AND bushes so that they fit perfectly together.
I tried to disassemble the pistons in order to check their pins, but once again the screws are tightened "to death" despite the
stoppers, and my ratchet wrench doesn't have a long enough lever arm ...

39
Friday, January 25, 2013

5H
P

Michel's package has arrived! Very carefully wrapped as usual, but you have to open it ...

VG

/A

M

IC
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E

Each piece or tool is packed separately so that they do not get damaged during transport.

G

There are the bearings for the gearbox, one of which is double, and the bearing for the transmission shaft (Michel even saves
us the trip to the shop!); the two parts of the primary shaft, bead blasted and its elements repaired; a screw for the connecting
rod cap; the two sleeves for the crankshaft bearing extraction tool, two extractors for the desperately glued cylinder head,
and steel corners if that's not enough ...
..

.

40

5H
P

I put back the input shaft in one piece

VG

/A

M

IC
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E

with its washer, waiting to reassemble the "A" box ...

G

At the end of the afternoon, I go down to the garage, and I'll start by extracting the crankshaft bearing bush. On the left, the
famous tool I used to extract the timing tappets on my 38 Traction engine

41

5H
P

… and I'm going to reuse all the parts except the bush ...

VG

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M

IC
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The new bush that's going to push the bearing

G

: it fits perfectly on the anti-friction bearing:

42

5H
P

…and its end will fit slightly into the bearing to centre itself. The outside diameter is a few hundredths less than the bore of the
bearing in the block:

VG

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M

IC
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…new bush that will receive the bearing,

G

…and whose inner diameter is a few hundredths larger than that of the collar of the bearing:

43

5H
P

To be able to screw without too much difficulty the threaded rod of 24 with a pitch of 300, I must slightly retouch the thread
of this bush...

G

VG

/A

M

IC
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Then I screw it on the threaded rod, and I block it with a (big) nut that will resume the thrust:

I put the tool in place:

44

/A

M

IC
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5H
P

…and screw it on. It's quite hard, without this "home-made" tool I would have butchered the bearing! Everything goes
perfectly as expected, the outer bushing goes into the block bore pushing the bearing into the inner bushing

VG

!

G

Now the outer nut has to be undone, and the whole thing has to be taken out:

45

VG

/A

M

IC
AL
E

The bearing is in very good condition, it has probably already been changed,...

5H
P

you can see the seizure marks in the bore of the crankcase. On engine A, the bearing was out with the thumb, but the engine
had not known salt water!

G

and there is no play on the crankshaft. We worked well on Skype for the design of the tool, and Michel (as usual) for its
realization.

46

5H
P

Well, now it's time to take out the cylinder head. On the A engine it took several days, with WD40 force and hammering on
various screwdrivers and chisels at the cylinder head gasket, which had come out very badly. Here, given the problems
encountered with each part, optimism is not appropriate...

.

G

VG

/A

M

IC
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E

So Michel made extractors that screwed into the spark plug wells. The inside is threaded for a screw that is supported on the
parting line of the block, between the valves and the cylinders.

The studs have been sprayed with WD40 for a few days.
I loosen the last nut with a "subtly" (!) rectified wrench:

:

47

5H
P

Put the tools on the cylinder head, I tighten the central bolts alternately, it's (very) hard,

G

VG

/A

M

IC
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… but it works ! Normal, it's "made by Michel" ...

/A

M

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5H
P

48

G

phew !

VG

Now it's getting really good, I was afraid that the cylinder head would twist and jam on the studs, but it did not.

,

There is at least one sand dune in this block, we thought it had been cooled via an exchanger, but it probably swallowed river
water or even sea water ...

M

IC
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E

The cylinder head gasket hasn't a scratch, but it will of course be replaced:

5H
P

49

/A

:

G

VG

I finish by extracting the valves, without much difficulty, but they are quite sick. The springs are single here, and not double as
on the A engine

.

Remains to remove the exhaust manifold and all the studs ...The End

50

Appendix : copy of Chapter 6.16 - MAGNETO SPROCKETS - Pignons
d'entraînement de la magnéto …
6.16 - MAGNETO SPROCKETS - Pignons d'entraînement de la magnéto

G

VG

/A

Here is this axle with its pinion ... completely dead !

M

IC
AL
E

5H
P

The magneto is driven in a slightly "twisted" way! Under the timing case (at the front of the engine) is of course the small
crankshaft pinion that drives the large pinion of the camshaft. On this last pinion is another one, which will drive at 90° a
pinion on a shaft connected to the magneto by a flexible coupling...


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