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jjbunn

TDC on the camshaft, and engine turning

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I'm wanting to set the valve clearances, but am having a bit of trouble setting TDC.

Here is a photo of the camshaft with what I believe is the TDC notch showing:

8587598008_de3115a632_b.jpg

(nearby the notch is another mark: "2", not visible in the photo).

What do I align the notch to ?

Also, how does one easily turn the engine manually? People talk about putting a spanner on the crankshaft pulley, but I can barely see in there, let alone get a spanner in - the fan is in the way. I can get some rotation by moving the fan itself, but part of the way round it slips. Putting the car in 4th and moving a rear wheel works, but it's too far from the engine compartment :-)

Thanks!

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Haynes manual has good info on this process, the factory repair manual on CD is also a good. Search function on the site is also recommended. Something about saving kittens is usually added at this point.

Anyway, the mark shown in the picture is the one you're looking for. Needs to be at 12 o'clock position. Both cam lobes down on the front cylinder. Pull the plugs and put a 32mm socket on the crank pully nut to turn the motor. Wear gloves so you don't shred your knuckles on the rad. Good luck buddy.

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pull the plugs, hold down the fan belt to make it tight, turn the fan to align the mark with the center of the end of the oiler tube (above the mark)

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Not sure why you want TDC. But I could be missing something.

Just watched the boys do this yesterday. They would rotate the cam lobe to be 180 degrees opposite where the rocker hit the cam. Slide a .007 feeler gauge in the slot, loosen the 10mm, move the eccentric to be snug on the feeler gauge. Tighten the nut ensuring you do not move the eccentric.

Double check the opening by seeing if a .008 will slide in. Mark the rocker to indicate it is done and move on.

Not having a fan and having an M3 crank, it was easy to move the motor with a 3/8" wrench and a socket.

We thought about getting the rear of the car in the air and with the car in gear, rotate the tires; it was late and cold and we were sissies trying to stay in the warm where there was light.

And to answer your question, TDC is aligning that notch to be under the oiler bar.

NathanandEvanadjustingvalves_zps5a8b73dd.jpg

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Yeah, I'm with Bill. No need for finding exact TDC. Just rotate engine until both lobes are pointing down for the rockers you want to adjust. As long as you're not on the lob or the edge of the lobe, you're fine for adjusting valves.

For rotating the engine, I just keep things simple, and don't bother to get tools out for that. Just put the car in gear and push the car a couple inches until the cam lobes are pointing downward for a different set of rockers. I just go back and forth a few times until I've covered all the rockers....

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Yeah, I'm with Bill. No need for finding exact TDC. Just rotate engine until both lobes are pointing down for the rockers you want to adjust. As long as you're not on the lob or the edge of the lobe, you're fine for adjusting valves.

For rotating the engine, I just keep things simple, and don't bother to get tools out for that. Just put the car in gear and push the car a couple inches until the cam lobes are pointing downward for a different set of rockers. I just go back and forth a few times until I've covered all the rockers....

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x3 bills and kens take.If you cannot move the car a 31mm wrench on the crank will work to bar the eng(out of gear),dont worry about tdc for valve adj....BE LIKE ME worry about timing with a aftermarket flywheel with no ball,,,,,,,,,,,,,, to top that it has a aftermarket crankpully that has 1 [email protected] 5 holes drilled init :/

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btw, bill it would be nice to have 4 hands to adj valves on a 300degree cam

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n Dog - Those are two good boys! I am sure they would love to help out. The friend of my son has a Mustang Cobra with a bizillion BHP to the rear wheels. He and my son did the new supercharger and suspension on it.

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pull the plugs, hold down the fan belt to make it tight, turn the fan to align the mark with the center of the end of the oiler tube (above the mark)

Thanks, Esty and everyone.

Yes, plugs are out. Car is on jack stands. Good tip about tensioning the belt. No way can I get a wrench on the pulley nut, I don't think.

I've done this before on LBCs, so am not a complete noob, but always learning :-)

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They would rotate the cam lobe to be 180 degrees opposite where the rocker hit the cam

that's how I do it, too.

Cams have ramps, and they're REALLY long- like 100 crank degrees or more.

So point the lobes down, and be sure.

And that mark you show should be exactly centered under the spray bar,

for tdc. There's a casting flash mark you align with, if the bar's off.

Plugs out- the M10 is civilized, you don't lash it hot like most vehicles.

t

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Ditto on removing the plugs, tightening the fan belt, and spinning the fan.

An easy way to be certain that the cam lobes are pointing down is to look at the cam lobes on the complimentary cylinder. That is, when cylinder #1 is at TDC -- when the cam lobes for #1 are pointing down and the rockers are on the flat part of the top of the cam -- the cam lobes for #4 are pointing up. So if you watch the #4 cam lobes and rotate the engine so that the lobes for #4 are "overlapped" -- that is, the lobes are opening the intake and exhaust valves by the same amount -- #1 will be on the flat spot on the back of the cam. Same with #2 and #3.

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Ditto on removing the plugs, tightening the fan belt, and spinning the fan.

An easy way to be certain that the cam lobes are pointing down is to look at the cam lobes on the complimentary cylinder. That is, when cylinder #1 is at TDC -- when the cam lobes for #1 are pointing down and the rockers are on the flat part of the top of the cam -- the cam lobes for #4 are pointing up. So if you watch the #4 cam lobes and rotate the engine so that the lobes for #4 are "overlapped" -- that is, the lobes are opening the intake and exhaust valves by the same amount -- #1 will be on the flat spot on the top of the cam. Same with #2 and #3.

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Ditto on removing the plugs, tightening the fan belt, and spinning the fan.

An easy way to be certain that the cam lobes are pointing down is to look at the cam lobes on the complimentary cylinder. That is, when cylinder #1 is at TDC -- when the cam lobes for #1 are pointing down and the rockers are on the flat part of the top of the cam -- the cam lobes for #4 are pointing up. So if you watch the #4 cam lobes and rotate the engine so that the lobes for #4 are "overlapped" -- that is, the lobes are opening the intake and exhaust valves by the same amount -- #1 will be on the flat spot on the top of the cam. Same with #2 and #3.

Tightening the belt did the trick - I can now rotate the engine easily. I'm starting with #1 and find the intake is a little too big at 0.009. Just how critical is the setting - I don't want to futz with it if 0.009 is good enough?

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