Cam Timing Question

[smestas]

I'm trying to follow along with Waynes book but I've gotten a bit lost with the cam timing. When both cams are set correctly will the keyways or cam markings both be pointing the same way? For example if one cam marking is pointing up should both cam markings be pointing up or should one be up and the other pointing down.

Thanks in advance!

[ChrisBennet]

Yes, the keyways and cam marking will point the same direction. As a quick check, the cams may not be straight up and down but they should both be "off" the same direction and amount. I.e. if the mark for the left cam is at 1 o'clock, the mark for the right cam should also be at 1 o'clock.
-Chris

[smestas]

Thanks Chris!

After searching the threads last night and reading horror stories I thought Id ask to be sure i got it all right.

Should the #1 intake and the #4 intake be opening at the same time in sequence or are they actually a 360 deg. crank turn from each other?

[smestas]

Originally posted by smestas
Should the #1 intake and the #4 intake be opening at the same time in sequence or are they actually a 360 deg. crank turn from each other?

I think you have already answered this right? If the cams were at their marks 360 deg apart then the marks would not be pointing the same way (both up or down).

I hope I got this right. Never the less Ill make sure she turns over by hand quite a few times.

[jpnovak]

When comparing 1 and 4 at Z1 two scenarios can happen. Both valves are closed indicating TDC or they are both open (somewhere near overlap depending on timing). Wiggle the rockers (if you set clearance) or watch them. they will be out of phase. For example, #1 will be at TDC (compression stroke) with both valves closed while #4 will be transitioning from exhaust closing to intake open on its exhaust stroke.

I am not sure about the keyway openings.

[Wayne 962]

Originally posted by smestas
I'm trying to follow along with Waynes book but I've gotten a bit lost with the cam timing. When both cams are set correctly will the keyways or cam markings both be pointing the same way? For example if one cam marking is pointing up should both cam markings be pointing up or should one be up and the other pointing down.

Thanks in advance!

Yes, they should be pointed the same way at all times.

-Wayne