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Re: Cylinder Head Removal, ROPE Method



Hello All,
    Save this one for the "rope method" of removing the cylinder heads.  I
searched through my old e-mail and could not find it anywhere.
The Rope Method:
Preface:  The intent of using this method is to remove a stuck cylinder
head.  Suspending the vehicle on  the engine pulling tabs will only stress
other components; wedges will trash the cylinder head beyond repair; and the
head pulling bracket may not work in all occurrences.   I have used this
method on several engines, one with all five studs seized, and in all cases,
the heads lifted about +1 inch, enough room to jab saw the studs up close to
the head.  Also in all cases, no connecting rods were bent.  Depending on
the reason you are removing the heads, it would be wise to pull the tappet
buckets and pallets to see if any valves are bent. If so, expect to find a
broken valve in the cylinder, and do not crank the engine without a length
of rope in the cylinder.  Otherwise, the valve piece will imbed itself into
the soft aluminum once for each rotation, and most likely trash your head.
Do not bother trying to soak the studs, the penetrant never goes more than
1/2 inch past the surface, no matter what the claim of the penetrant.  But,
if it makes you feel good, go ahead and spray away, the runoff will help
loosen the grease cake on the side of the engine.  Also, DO NOT attempt to
weld anything onto the broken off stud(s), it will only damage the bolting
washer surface which needs to be perpendicular to the stud axis.  It would
be a good idea to view Tony Hart's timing chain video first, available from
Tony Hart, the SOC, or Rimmers.  Tony does not stock US formats of the
video.

Materials needed:
-a lot of patience, but hell, you have tried every method known to man
already, so push on;
-normal automotive hand tools;
-gear puller;
-a stud extractor/vice grips with GOOD jaws;
-8 to 12 feet of 3/8" braided nylon rope;
-a working starter;
-a charged battery;
-a battery charger;
-spray lube oil/penetrant like WD40 or equivalent;
-long thin screwdriver or 1/4 inch wooden dowel;
-a remote hand start button (not necessary, but keeps you from running back
and forth to the ignition key);
-a hand jab saw...I do not recommend using a power saw, as you can severely
damage your head beyond repair.  A little patience and elbow grease using a
hand jab saw and good quality blade, renewing the blade as necessary, will
save you the grief from realizing that you went through all this trouble
just to trash a head.  A jab saw is a hack saw/metal saw with no holder on
one end of the blade;
-a 1/4 inch drift pin, or tapered drift pin;
-a 10 pound hand mallet;
-about 4 hours of patience and labor;
-a sauna or hot tub, several pints of your favorite brew (for use
afterwards)

Initial Procedure: (basically, remove everything from the engine)
-pull fuses for the fuel pump, and all electrical accessories
-drain radiator and engine block
-remove intake manifold, power steering pump, A/C bracket, radiator, fan,
torquatrol;
-Turn crank to TDC #2, remove harmonic balancer using a gear puller;
-remove timing chain cover, timing chains, mark crankshaft and jack shaft
positions on the block, remove cams, spark plugs;
-remove all cylinder head studs and nuts that can be removed;
-disconnect hoses and electrical connections from rear of  cylinder heads;
-replace the harmonic balancer onto the crankshaft, without the center bolt;

-spray a penetrant oil into each cylinder, hand cranking the engine as
necessary to get the cylinder bores lubricated-if you have an air hammer, it
would be a good idea to air hammer the studs, as this helps break them free
from the cylinder head.

Regards,
Glenn Merrell
"Keep Your Stag Cool, Install a NEW Composite Cowl Today"
http://pw1.netcom.com/~gmerrel/stagcowl001.html



Overview:
    The basic idea using this method is to use the power of the starter to
move the piston at velocity, compressing the nylon rope against the cylinder
head.  Not to worry, combustion explosion in the cylinder exceeds 2000 psi.
This compression, when repeated several dozen times, will break the stud
free enough to lift the cylinder head about one inch.  The sequence to be
followed is open to the user, but I have found it best to start with the
front cylinder and work my way back until I see how the head is lifting.  If
some studs are giving you a particularly hard time, concentrate on the
cylinders on either side of the stuck studs.  RESIST ALL TEMPTATIONS TO USE
A PRY BAR AND WEDGES.

Removal Procedure:
1.  with one hand, place the long screwdriver or dowel into the spark plug
hole of the stuck head;
2.  rotate the crank counter clockwise (CCW)  with the other hand until the
piston is at the bottom of its stroke, using the dowel as an indicator;
3.  remove the screwdriver and carefully feed the nylon rope into the
cylinder through the spark plug hole, leaving a loop exposed to remove the
rope...DO NOT INSERT ALL OF THE ROPE INTO THE CYLINDER, AS YOU MAY NOT BE
ABLE TO RETRIEVE IT!!!;
4.  rotate the crank by hand to compress the rope in the opposite direction
(CCW) from the normal rotation.  Tick over the engine using the starter.
RELEASE THE KEY/REMOTE BUTTON AS SOON AS THE crankshaft STOPS ROTATION, OR
YOU WILL BURN OUT YOUR STARTER.  The engine rotation sill stop with a dull
thud.  The starter is not strong enough to push the head up with normal
rotation.  It needs the counter rotation to bet enough momentum to strike
the head with the rope in the cylinder
5.  Rotate the crankshaft CCW in the full opposite direction  by hand to
compress the rope in the opposite rotation:
6.  tick over the engine using the starter, again releasing as soon as the
crankshaft stops rotation;
7.  rotate the crankshaft CCW to the bottom of its stroke, feed in more rope
if necessary (you will know if it is necessary if the engine cranks several
full rotations);
8.  rotate the crankshaft CCW by hand to compress the rope in the opposite
direction;
9.  tick over the engine using the starter, again releasing as soon as the
crankshaft stops its rotation:
10.  REPEAT steps 5-9 until you see some movement of the cylinder head,
which may be 10-20 times, then;
11.  rotate the crank CCW to loosen the rope, remove the rope from the
cylinder, move to the next cylinder, start at step #1;
12.  when the head has lifted to a distance of about one inch, move the
cylinder head gasket up against the bottom of the cylinder head.  This is to
insulate the head from the jab saw;
13.  carefully, jab saw the stud as close as possible to the head, being
careful not to contact the head;.  This will give you a one inch stud to
grab with a stud extractor or vice grips.
The fun part...
14.  support the cylinder head on some wood blocks;
15.  drive the head studs out of the head with the drift pin and 10 pound
mallet (ohhh..yes, this feels soo good, wear some good gloves and goggles)
16.  repeat for second cylinder head
17.  go sit in the sauna, drink a beer.


Richard Brake wrote:


>   For the last two months I have been trying to remove a Stag cylinder
> head. This head has two broken studs which have sheered off level with

> the head. My daily routine is soak with Oil or Hyperclean then hit head
> with a 4lb hide hammer approx 50 times. I have shifted the head up about
> 16th to an 8th of an inch. This has decompressed the gasket but not
> allowed me the clearence to insert a hacksaw and so cut off the accursed
> studs (the way I removed the other head).
>
> I have jacked the car up on the exhaust manifold and even suspended it
> from the garage roof by the exhaust manifold to provide some tension to
> the head before hitting it.
>
> Has anyone got the plans for the SAAB based tool for head removal. This
> bolts to the inlet and exhaust faces of the
> head and allows bolts to screw down onto the relevant studs thus jacking
> the head up.
>







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