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Re: Flats on the camshaft
Flats on a camshaft usually refer to the flat sections the manufacturers provide that you can put the correct size open end spanner over to hold the cam in the correct position when setting up the cam timing. Often the valve spring pressure tries to rotate the cam into the wrong position for setting up the chain or belt, and that's why they have these flats. That's the only use of that terminology that I'm aware of, hope it helps.
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sorry no idea ,bring no1 piston to top of engine ,then look for marks on cams if no marks on sprockets then take rocker cover off and look at back of cam for the slots or flats ,this engine is the same as a opel zafira basicly and i seem to remember the flats on the back of the camshafts and slots on a ford .At my age memory is a luxury
measure across the flats of the nut and that is the size of the socket
for example it it measures 1" across the flats then you will need a 1" af socket
if it is a metric nut then measure across the flats and then take the measurement to a good tool shop and find a socket that has that measurement across the flats
You must use a special tool which bolts onto the cylinder head. It is designed to hold the camshafts in the proper position. It goes over the flats on the camshafts to hold the camshafts in the correct position. This tool can be rented. Look on EBay or check with your local Snap On Tools, Mac Tools, or Matco Tools dealers to rent one. See the link below for photos of properly aligned timing marks for your engine.
below are the instruction you well need to remove head .....good luck
Remove the air cleaner element.
Remove the air cleaner outlet resonator. .
Remove the powertrain control module (PCM) and engine wire harness bracket and related hoses and connections.
Remove the generator.
Remove the intake manifold.
Remove the exhaust manifold. Do not remove the exhaust pipe from the manifold. Only have the manifold pushed off to the side of the engine.
Position the A/C line out of the way towards the front of the vehicle.
Disconnect the following cross-vehicle engine wiring harness connectors:
Engine coolant temperature sensor
Manifold absolute pressure (MAP) sensor
Harness clamps at power steering pump
Wiring harness fastener at the right front inner fender
Heated oxygen sensor (HO2S)
Set aside the cross-vehicle engine wiring harness on the left side of the vehicle.
Remove the camshaft cover.
Partially drain the cooling system.
Before performing one of the top dead center (TDC) procedures, break loose both the exhaust and intake camshaft sprocket bolts. Use a 25 mm (1 in) open end wrench on the camshaft hexes to hold the camshaft from turning. DO NOT remove the bolts.
Perform one of the following methods for the service timing procedure.
First Method--Rotate the engine clockwise by hand to TDC on the compression stroke by using a piston TDC indicator tool and/or dial indicator in the number 1 cylinder.
First Method (continued)--The TDC indicator tool graduation marks on the shaft should note top of the piston stroke.
First Method (continued)--When the piston is at TDC, the flats at the rear of the camshafts will be facing up and level when using a straight edge across the camshaft flats.
Second Method--Rotate the crankshaft in the engine rotational direction clockwise until the number 1 piston is at TDC on the compression stroke. The word Delphi on the exhaust camshaft position actuator will be parallel with the cylinder head to cam cover mating surface. When the piston is at TDC, the flats at the rear of the camshafts will be facing up and level when using a straight edge across the camshaft flats. A 0.005 inch feeler gauge should not slide under the straight edge (1).
Use a white paint pen or equivalent to place a reference mark on the harmonic balancer to the front cover for alignment purposes.
Lower the vehicle.
Important: If the timing is correct (TDC compression stroke number 1 cylinder), the camshaft flats will be in the up position.
Install J 44221 to the back of the camshafts.
Remove the upper timing chain guide to the cylinder head.
Clean the timing chain and gears with brake cleaner or suitable solvent. Use a white paint pen or equivalent to place a reference mark on both timing gear sprockets and the timing chain to mark location prior to disassembly. It is recommended that the paint marks be in the 12 o'clock position.
Install EN-48464 . It is important to install the tool with the proper orientation and to ensure that it is seated square against the timing chain and against the timing cover center bolt.
The narrow ramp of the wedge tool needs to be placed so that it faces the timing chain.
The wedge tool should be lightly seated using a couple of very light taps with a small plastic or brass hammer. The wedge tool will be fully seated against the tensioner after it moves about 25 mm (1 in).
Once the tool is correctly installed, unscrew the handle and remove the handle
Remove both upper cylinder head access hole plugs from the front of the cylinder head.
Remove the 1 long and 2 short cylinder head bolts next to the exhaust and intake timing chain tensioner shoes and discard the bolts.
Remove both upper timing chain tensioner shoe bolts.
Remove the exhaust and the intake camshaft sprocket bolts. Discard the bolts.
Carefully remove the exhaust and intake camshaft sprockets with the timing chain from the exhaust and intake camshafts. The illustration shows the exhaust camshaft sprocket already removed.
Remove the sprockets from the chain, tie a piece of mechanic's wire on the timing chain and let it drop.
Before removing the cylinder head bolts, use a drift punch and hammer to shock the bolts. This will ensure that the cylinder head bolts will not strip out the threads in the engine block or break. If a bolt breaks during engine disassembly, EN-47702 is available to assist in the removal of the remaining bolt segment.
Remove the cylinder head bolts. Discard the bolts.
Remove the cylinder head.
Place the cylinder head on a flat, clean surface with the combustion chambers face up, in order to prevent damage to the deck face.
Remove the cylinder head gasket.
Discard the gasket.
Remove all remaining gasket material from the engine block.
Inspect the cylinder head gasket mating surface on the engine block.
Before servicing the vehicle, refer to the precautions in the beginning of this section.
Relieve the fuel system pressure.
Remove or disconnect the following:
Negative battery cable
Crankcase ventilation tube from the valve cover
Spark plug cover bolts and the cover
Spark plug wires from the plugs
Camshaft Position (CMP) sensor connector
Valve cover nuts, washers, cover and gasket
NOTE: Be very careful not to nick or scratch the camshafts.
Hold the flats of the intake camshaft in position using an open ended wrench and remove the camshaft gear bolt. Remove the gear.
Hold the flats of the exhaust camshaft in position using an open ended wrench and remove the camshaft gear bolt. Remove the gear.
Mark the camshaft cap locations so that they may be returned to their original positions.
Remove the camshaft cap bolts in several passes of one half turn each in the sequence illustrated.
Remove the seal ring from the camshafts.
NOTE: Make sure the camshafts detaches evenly from the bearing seats in the front guide bearing.
Remove the caps and the camshafts.
Fig. 3: Remove the camshaft cap bolts in several passes of one half turn each in the sequence illustrated - 2.0L and 2.2L engines
Lubricate the camshafts and caps with engine oil.
Install the caps and the camshafts in their original positions.
Tighten the camshaft cap bolts in the sequence illustrated to 71 inch lbs. (8 Nm).
Fig. 4: Tighten the camshaft cap bolts in the sequence illustrated using several passes - 2.0L and 2.2L engines
Measure the camshaft endplay on both camshafts. The endplay should be 0.0015-0.0056 in. (0.040-0.144mm).
Install the intake camshaft gear. Hold the flats of the intake camshaft in position using an open ended wrench and tighten the camshaft gear bolt to 37 ft. lbs. (50 Nm), retighten the bolt an additional 60 degree turn and finally an additional 15 degree turn.
Install the exhaust camshaft gear. Hold the flats of the exhaust camshaft in position using an open ended wrench and tighten the camshaft gear bolt to 37 ft. lbs. (50 Nm), retighten the bolt an additional 60 degree turn and finally an additional 15 degree turn.
Install or connect the following:
Valve cover, washers and nuts. Tighten the nuts to 71 inch lbs. (8 Nm).
CMP sensor connector
Spark plug wires to the plugs
Spark plug cover and bolts. Tighten the bolts to 27 inch lbs. (3 Nm).
Rotate the crank so the mark on the sprocket is at the 5 o'clock position
Assemble chain to the intake camshaft sprocket alignment copper link to the "INT" diamond timing mark on the camshaft sprocket
NOTE: When lowering the timing chain rotate the assembly 90° to allow the chain to fall between the cylinder block bosses then rotate the assembly back so the camshaft sprocket is facing forward.
Lower the assembly through the chain housing opening on top of the cylinder head. Use care to ensure that the chain goes around both sides of the cylinder block bosses
NOTE: The crankshaft sprocket timing mark will be at approximately the 5 o'clock position.
Route chain around crankshaft sprocket and align silver link to the timing mark
NOTE: The camshaft sprocket bolts are not reusable; they are torque-to-yield and must be discarded to prevent premature failure.
Install or connect the following:
Intake camshaft sprocket loosely onto the intake camshaft then install the new camshaft sprocket bolt finger tight
NOTE: It is not necessary to align the sprocket-to-camshaft offset notch at this time.
Adjustable timing chain guide through the opening on top of the cylinder head then install the chain guide bolt; torque to 89 lb-in. (10 Nm)
Exhaust camshaft sprocket loosely onto the exhaust camshaft with the timing mark on the sprocket aligned with the silver link then install a new camshaft sprocket bolt finger tight
NOTE: It is not necessary to align the sprocket-to-camshaft offset notch at this time. NOTE: The camshaft sprocket bolts are not reusable; they are torque-to-yield and must be discarded to prevent premature failure.
Align the camshaft sprocket-to-camshaft then tighten the camshaft bolt using the following procedure:
NOTE: Do not rotate either camshaft more than 1/2 turn in either direction with the crankshaft at Top Dead Center (TDC). To do so may cause valve to piston contact resulting in a damaged valve and/or a damaged piston.
Ensure that the sprocket timing mark is at the 5 o'clock position
Rotate the intake camshaft using a 24mm wrench on the flats of the camshaft until the sprocket-to-camshaft alignment notch seats
When the sprocket seats on the camshaft tighten the sprocket bolt finger tight
Rotate exhaust camshaft using a 24mm wrench on the flats of the camshaft until the sprocket-to-camshaft alignment notch seats
When the sprocket seats on the camshaft tighten the sprocket bolt finger tight
Verify that all colored links are aligned with the appropriate marks on the camshaft and crankshaft sprockets
NOTE: If they are not repeat steps 1C through 4.
Install the fixed timing chain guide and bolts; torque to 89 lb-in. (10 Nm)
Install the fixed timing chain guide bolt access hole plug; torque to 30 lb-ft. (40 Nm)
Install upper timing chain guide and bolts; torque to 89 lb-in. (10 Nm)NOTE: Use a 24mm wrench to support the camshaft while applying torque to the camshaft sprocket bolt. Do not torque the camshaft bolts against the timing chain as it may damage the timing chain.
Torque the intake and exhaust camshaft sprocket bolts; torque as follows:
First Pass: 63 lb-ft. (85 Nm)
Second Pass: Turn an additional 30° using a torque angle gauge
Install the sealing ring and tensioner assembly; torque to 55 lb-ft. (75 Nm)
Install or connect the following:
Timing chain oil nozzle and bolt; torque to 89 lb-in. (10 Nm)
Camshaft cover assembly
Engine front cover
Negative battery cable; torque to 13 lb-ft. (17 Nm)
Assuming you have the single overhead camshaft, there is a pin you're supposed to use to align the camshaft gear--see below diagram from autozone.com:
Obviously you could substitute a phillips screwdriver of the appropriate size for the alignment pin shown. Leave it in until you complete the chain installation.
The crankshaft pully mark goes straight up:
Make sure the chain is tight on the right side when the gears are in these positions and that it doesn't slip any teeth on eight gear when you apply the tensioner. I will paste the autozone instructions below.
Inspect the chain for wear and damage. Check the inside diameter of the chain, it should be no more than 16.77 in. (426mm). Inspect the chain guides for wear or cracks and the timing sprockets for teeth or key wear. Replace components as necessary.
Verify that the crankshaft is positioned 90 degrees clockwise past TDC from the keyway (keyway at 3 o'clock).
Bring the camshaft up to No. 1 TDC by loosely installing the sprocket and rotating the sprocket until the timing pin can be inserted. The camshaft contains wrench flats to assist in turning the shaft. The dowel pin should be at 12 o'clock when the camshaft is at TDC and a timing pin ( 3 / 16 in. drill bit) should then install at about the 8 o'clock position.
If removed, install the crankshaft sprocket, then rotate the crankshaft counterclockwise 90 degrees up to No. 1 TDC (keyway at 12 o'clock).
Position the chain under the crankshaft sprocket and over the camshaft sprocket. If necessary remove the camshaft sprocket, then slide the camshaft sprocket into position with the chain already engaged. The timing chain should be positioned so that one silver link plate aligns with the reference mark on the camshaft sprocket and the other aligns with the downward tooth (at the 6 o'clock position) on the crankshaft sprocket. The letters FRT on the camshaft sprocket must face forward, away from the cylinder head and excess chain slack should be located on the tensioner side of the block.
Temporarily install the timing pin to verify proper alignment of the camshaft and sprocket, then install and tighten the sprocket bolt to 75 ft. lbs. (102 Nm). Again, use a wrench on the camshaft flats to hold the shaft in position while tightening the bolt. Do not allow the camshaft retaining bolt to torque against the timing pin or cylinder head damage will result.
Install the chain guides with the words FRONT facing out. Install the fixed guide first and verify the chain is snug against the guide, then install the pivot guide. Tighten the bolts to 19 ft. lbs. (26 Nm) and verify that the pivot guide moves freely.
Retract the tensioner plunger and pin the ratchet lever using a 1 / 8 in. No. 31 drill bit inserted in the alignment hole at the bottom front of the component. Install the tensioner and tighten the bolts to 14 ft. lbs. (19 Nm), then remove the drill bit.
Make one final check to verify all components are properly timed, then remove all timing pins.
Install the timing chain front cover.
Connect the negative battery cable, start the engine and check for leaks.
Flats of all four cams on the ends opposite gears need to be parallel to top of head where cam cover bolts on. Dark links on transmission side of cam gears should line up with pins at 12:00 positions on cams. Dark links on pulley side of gears should line up with marks on intake gears. Dark link on balancer shaft gear lines up with tooth at 5:00 position. Dark link on crankshaft gear lines up at 4:00 position.
Here is a diagram of the pulley side marks.
Here is what the marks look like on the tranmission side of the gears on the front head:
Find more pix on the head gasket page of 99intrigue.shutterfly.com
If there is no decal on the underside of the hood, or in the engine compartment somewhere... wrap it around the crankshaft, and work your way around, putting ribs to ribs, and flats to flats. There may be a couple of combinations, but you'll get it.
As best I can tell, it is a flat area machined into the cams of a dual overhead cam GM V6 engine. These flat areas are used to align the (4) camshafts during timing belt installation. I found a link on the web which details timing procedures, with photos. There also appears to be special tools required for this procedure.