3.6 cam Timming

[adeak1]

Dear All

I just checking that I did all think correctly

Timing mark (dot) not on passenger side Cam?

1) Found TDC on #1 (Dot on cam set straight up)
2) Adjusted rocker arms for Go-No-Go on (.0025 passed under rocker-003 do not pass) 911 Valve Adjustment the Backside Method
3) Rotated 360 degree for 1.26 on intake side and adjusted cam timing for the center on case split.
4) Check two more time
5) Set TDC for #1
6) Rotate 360 for TDC #4 (No Dot on Passenger cam- I move cam until both rocker where moving- A good starting point)
7) Adjusted rocker arms for Go-No-Go(.0025 passed under rocker-003 do not pass) 911 Valve Adjustment the Backside Method
8) Rotated 360 degree for 1.26 on intake side and adjusted cam timing for the center on case split
9) Check two more time
10) Installed rockers on 2,3,5,6
11) Set #1 to TDC checked #1 (go-no-go on #1)
12) rotate 120 degree (go-no-go on #6)
13) rotate 120 degree (go-no-go on #2)
14) rotate 120 degree (go-no-go on 4)
15) rotate 120 degree (go-no-go on 3)
13) rotate 120 degree (go-no-go on 5)
14) rotate 120 degree for TDC #1 and install distributor at the timing mark

The only thing I was not sure was the passenger side cam starting position? It look like I got it.



I thing this correct but I will check with group

Thank for the Help
Andrew

[brp914]

I've done timing on 2.0 thru 3.2, but didn't understand some of your descriptions, so I can't answer your question. But, I'll be doing a 3.6 soon and I'd like to know if you used the factory tools to tension the chains in this process.

[adeak1]

Dear brp914

I do not have the factory tensioner, but I using the DVD on 964 engine rebuilding (host sells) and they use the cars normal tensioner installed when timing cams. I hope this helps.

What in the descriptions do you not under stand? I may have the wrong descriptions for the procedure.

Thanks

Andrew




Andrew

[pors1968]

To brp914 i used small soket Under the ramp to keep tension the chain.

[Walt Fricke]

My experience is that if you get one cam set right, and the other cam set 180 degrees wrong, you can still rotate the motor with just the #1 and #4 intake rockers installed. But as you continue installing the remaining 10 rockers, you will have a valve hitting a piston, which you will notice as you rotate the engine with a wrench as part of installing things. At which point you will slap your hand on your forehead, and go back and redo the offending cam.

[Eagledriver]

Originally Posted by Walt Fricke

My experience is that if you get one cam set right, and the other cam set 180 degrees wrong, you can still rotate the motor with just the #1 and #4 intake rockers installed. But as you continue installing the remaining 10 rockers, you will have a valve hitting a piston, which you will notice as you rotate the engine with a wrench as part of installing things. At which point you will slap your hand on your forehead, and go back and redo the offending cam.

I don't think so Walt. In fact I've seen several stories on here of people that had installed one cam 180 out. The engine turns over fine and will run on 3 cylinders. If you could get the number 4,5,6 cylinders to fire at the same time as number 1,2,3, it would probably have almost as much power. I think it would run a little rough however!

-Andy

[Walt Fricke]

Well, that was my experience when I had it wrong. The guy I helped put his motor together called me when he ran into the problem. SC with a 964 cam. I was gratified to find several guys much better than I at assembling motors had had the same issue - got distracted during the cam timing, maybe went back for cam 2 the next day.

But that is just my experience.

[adeak1]

Dear All

1)If my theory is correct when I am at TDC #1 both intake and exhaust rocker are not engaged? I am at the firing time for number one cylinder. One or more rocker are engaged on rocker 2,3,4,5,6
2)If I rotate 120 degree to TDC for #6 and both intake and exhaust rocker are not engaged.I am at the firing timing number six cylinder. One or more rocker are engaged on rocker 1,2,3,4,5
3) rotate 120 degree to TDC for #2 and both intake and exhaust rocker are not engaged


If I rotate thru the rest of the TDC for each cylinders the only cylinders with both intake and exhaust rocker not engaged are the cylinder that will be firing?

Firing order is 1,6,2,4,3,5

I believe I cam can not be 180 degree out if my theory is correct?

And again I had no timing mark on the passage cam?

Thanks for the help
Andrew

[Flat6pac]

If the cam says 930 or 964 on it, thats up, same as the dot.
I have gone to lunch when timing cams and had one 180 out. Pull the distributor, spin it 180 and run on the other 3 cylinders.
I dont take a break setting cams anymore...get the numbers and have a beer.
Bruce

[Eagledriver]

Originally Posted by adeak1

Dear All

1)If my theory is correct when I am at TDC #1 both intake and exhaust rocker are not engaged? I am at the firing time for number one cylinder. One or more rocker are engaged on rocker 2,3,4,5,6
2)If I rotate 120 degree to TDC for #6 and both intake and exhaust rocker are not engaged.I am at the firing timing number six cylinder. One or more rocker are engaged on rocker 1,2,3,4,5
3) rotate 120 degree to TDC for #2 and both intake and exhaust rocker are not engaged


If I rotate thru the rest of the TDC for each cylinders the only cylinders with both intake and exhaust rocker not engaged are the cylinder that will be firing?

Firing order is 1,6,2,4,3,5

I believe I cam can not be 180 degree out if my theory is correct?

And again I had no timing mark on the passage cam?

Thanks for the help
Andrew

You are correct. If you had one cam 180 out, 2 cylinders would have un engaged valves at the same time.

-Andy

If it helps to think about it, the act of installing the cams determines which Z1 is for number 1 and which is for number 4. Before the cams are installed the Z1 is undefined. If you install the cams both 180 out you really have installed them correctly again. It's only if one is up and the other down that you have them "out of phase".

[adeak1]

Dear Andy

Thanks Andy I can now put the engine back together. I did not want to install the engine and have the cam out of time. I will check the setting one more time and I will be running soon.
Thanks for the definitive answer on cam timing.

Andrew

[earossi]

I believe that without a mark on the front of the cams, you should start out with both Woodruff key slots facing up.

And, it sounds as though you did the timing correct to me. I just completed essentially the same procedure on my 993 3.6, which I back dated to the old adjustable cam gear timing used on earlier designs. So, neither of my cams had any markings on the face. So, my static setting was TDC on #1 coinciding with both cams set with the key slots facing up. One of the keys to having done it correctly, is that the timing needs to be as close to the same on both sides of the motor. For instance, if you were able to hit the timing so that you were, in fact, at 1.26 mm at TDC on #1, you should move on to timing the #4 intake, and attempt to duplicate the 1.26 mm on that side of the engine (at TDC for #4). Putting it another way, hitting the 1.26 mm at TDC is secondary to making certain that #1 and #4 intakes are open the same amount at TDC.

Proof is that the car is now running fine!

I think you nailed it!

[adeak1]

Dear All

Third Try and engine started. Engine is running with no oil leaks so far (20 min) I will be ready for a nice Sunday drive.

Thanks for all your Help

Andrew