Tdc
luy123
11-12-2005, 08:08 PM
I have a '96 Sable. I have to change the Camshaft Position Sensor as well the vane that gives it info. My manual says to make sure you are at TDC. With the "newer" cars without timing marks what's the best way to do this. Putting a pen or something in #1 cylinder seems to me that you could be a few degress out either way. Thanks Andrew
burrelld
11-19-2005, 03:39 AM
I have a '96 Sable. I have to change the Camshaft Position Sensor as well the vane that gives it info. My manual says to make sure you are at TDC. With the "newer" cars without timing marks what's the best way to do this. Putting a pen or something in #1 cylinder seems to me that you could be a few degress out either way. Thanks Andrew
Oh, the timing mark is there on the standard OHV 3.0L engine, but Ford made it almost impossible to see. What you have to do, or what is quicker to do, is remove the belt from alternator/power steering pump/ etc. etc. and get it out of your line of sight.
This will allow you a view of the 6 groove crankshaft pulley down at the very bottom of the engine. Located right behind that pulley, almost against the engine front cover, you'll see the crankshaft damper. As you look down on that damper, to the left, is a bolt head on the engine front cover. Right next to that bolt is a "sort of" pointer attached to the engine cover. Mark that dead center with a thin stroke of white paint....A small watercolor brush and latex house paint works well.
On the crankshaft damper, if you look long and hard enough, you'll finally find a long groove in the metel. Clean that off with mineral spirits, let it dry and then stroke white paint into that grove. That way you'll be able to see both the pointer and the groove down there in the deep shadows.
When they both match up, one of your cylinders will be at TDC. Keep going until number one is at TDC. That you can do with a screw driver as a guide. Better still, get a compression gauge and use that in place of the screw driver. When you start getting a pressure reading on the gauge you are getting close to TDC. The damper also has other smaller graduation marks (BTDC) etc.
You can crank the engine over either by hand, with a large socket and breaker bar, or with someone "blipping" the key to crank the engine in small spurts to get close to TDC. Correct rotation of the crankshaft pulley when setting the TDC by hand is CLOCKWISE, and the final positioning will always have to be done with the breaker bar and socket.
Before you start doing anything, put the car in PARK, engage the parking brake, and disconnect the ignition wiring harness connector from the side of the coil pack assembly. You don't want the car to "fire" when you are doing any of the above
Oh, the timing mark is there on the standard OHV 3.0L engine, but Ford made it almost impossible to see. What you have to do, or what is quicker to do, is remove the belt from alternator/power steering pump/ etc. etc. and get it out of your line of sight.
This will allow you a view of the 6 groove crankshaft pulley down at the very bottom of the engine. Located right behind that pulley, almost against the engine front cover, you'll see the crankshaft damper. As you look down on that damper, to the left, is a bolt head on the engine front cover. Right next to that bolt is a "sort of" pointer attached to the engine cover. Mark that dead center with a thin stroke of white paint....A small watercolor brush and latex house paint works well.
On the crankshaft damper, if you look long and hard enough, you'll finally find a long groove in the metel. Clean that off with mineral spirits, let it dry and then stroke white paint into that grove. That way you'll be able to see both the pointer and the groove down there in the deep shadows.
When they both match up, one of your cylinders will be at TDC. Keep going until number one is at TDC. That you can do with a screw driver as a guide. Better still, get a compression gauge and use that in place of the screw driver. When you start getting a pressure reading on the gauge you are getting close to TDC. The damper also has other smaller graduation marks (BTDC) etc.
You can crank the engine over either by hand, with a large socket and breaker bar, or with someone "blipping" the key to crank the engine in small spurts to get close to TDC. Correct rotation of the crankshaft pulley when setting the TDC by hand is CLOCKWISE, and the final positioning will always have to be done with the breaker bar and socket.
Before you start doing anything, put the car in PARK, engage the parking brake, and disconnect the ignition wiring harness connector from the side of the coil pack assembly. You don't want the car to "fire" when you are doing any of the above
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