Cam Timing Question

Strype

Cuthbert catcher
Founding Member
May 11, 1999
61
35
104
Huntsvegas, AL
Sorry for so many questions guys...

When we put my cam in we made sure that the #1 piston was at TDC and the cam gear + Crank were lined up. Then we put the heads on...

Question:

Do you have to make sure that the intake valve is the first one hit at that point or does it matter. I'm getting guys telling me that I built the car on the exhaust stroke, and another guy is telling me that everything resets at that point and it doesn't matter once you take the cam and distributor out...


Who's right? :shrug:

Do you have to put the heads on before the cam to ensure that it's on an intake stroke????

You guys are a blessing so far. I'm gonna put a big Stangnet sign in the window :nice:
 
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No, you do not need to install the cam "on the intake stroke." The cam determines where/when the intake stroke occurs, not the crankshaft.

As long as the cam was installed as you describe, crank dot (at 12) aligned with cam dot (at 6), the cam timing is okay.
 
No, you do not need to install the cam "on the intake stroke." The cam determines where/when the intake stroke occurs, not the crankshaft.

As long as the cam was installed as you describe, crank dot (at 12) aligned with cam dot (at 6), the cam timing is okay.

But I did not check to see if the motor was at TDC before the install- I don't think-

Still doesn't matter?
 
Sorry, that was something I should have clarified.

Was the timing set adjustable? Did the crank sprocket have multiple keys?

If no, you're okay. The crank sprocket will only install one way.

If it does, yes it matters.
 
Non adjustable stock type double roller...

Then my buddy put the dizzy in facing the actual #1 piston at a 10:00 position or so. Then we got gas out of the exhaust with an oily mix and some if not all of the spark plugs are soaking wet with gas.

My take is that I need to rotate the dizzy back to undo what he did, and check for a stuck fuel injector. Another friend says that since we didn't check if the motor was at TDC before we took the heads off and cam out that it's a cam timing issue and that is what is causing the gas in the exhaust. The fuel pressure drops off in less than 2-3 seconds.

I also have gas in the oil pan because I can smell it on the dipstick.

So either
A) I have a stuck injector and it's out of time

or
B) The cam and crank are out of sync


I don't know I'm so frustrated I don't even want to look at the car anymore :nonono:

I need help badly and I don't know what to do. When I prime the fuel pump I can hear a sound like on of the injectors is open and I can hear fuel moving through the rails, but again the other friend says that it could be a hole in the top of the piston.

I'm about to quit. My nerves can't take it. :(
 
Okay, non adjustable. As long as you had the cam timed to the crank (dot-to-dot), the cam should be installed correctly.

After reading your initial post a second time, I'm convinced the distributor is still installed in the wrong position. This needs to be corrected prior to investigating other potential causes. i.e fuel leak, open injector, etc.

Did you buddy have cyl #1 at TDC of the compression stroke prior to dizzy install? If so, how was it confirmed?

Also, when trying to find the compression stroke of the #1 cyl with the spark plug removed, the sound of the compression venting out the plug hole is pretty loud. You know immediately when both valves have closed and when the #1 piston is on the compression stroke.
 
Okay, non adjustable. As long as you had the cam timed to the crank (dot-to-dot), the cam should be installed correctly.

After reading your initial post a second time, I'm convinced the distributor is still installed in the wrong position. This needs to be corrected prior to investigating other potential causes. i.e fuel leak, open injector, etc.

Did you buddy have cyl #1 at TDC of the compression stroke prior to dizzy install? If so, how was it confirmed?

Also, when trying to find the compression stroke of the #1 cyl with the spark plug removed, the sound of the compression venting out the plug hole is pretty loud. You know immediately when both valves have closed and when the #1 piston is on the compression stroke.

Yea I'm convinced the dizzy is in the wrong spot too. He tried putting his finger over the #1 plug hole but never felt compression.

All I know is, we didn't make sure that the car was at TDC before the install. We installed the cam point to point with the crank. We installed the heads. He put the dizzy in with the rotor pointing at the #1 piston instead of the #1 plug wire under the cap. After that we tried to crank it and gas is coming out of the exhaust in several places along with what looks like oil. It could be the new exhaust had an oily coating, but it could also be oil. And there is gas in the oil pan. The fuel pressure won't hold when the key is turned forward, it will build and then release immediately.

I am at a loss.

I turned the dizzy around yesterday and it tried to crank but wouldn't. I guess the motor is blown along with my brand new GT40X heads. If so I will jump off a cliff.
 
Don't worry man. I'm sure the motor is fine (heads included), just have bugs to work out. It's expected after a project of this size.

I just noticed that the passenger side valve cover is off. That's great! Finding TDC of the compression stroke will be easier.

1) Rotate engine by hand (clockwise) until intake valve for #1 cylinder starts to open.
2) Keep rotating until #1 intake valve closes. Stop. You are now on the compression stroke.
3) Check balancer timing marks. Align balancer to pointer at 10* BTDC.
4) Check dizzy cap for #1 terminal location (the factory mark). Mark this position on the dizzy.
5) Install dizzy. Point rotor to mark corresponding to #1 terminal location.
6) Install cap.

Out of curiosity, do you have pedestal or stud mount rockers?
 
Don't worry man. I'm sure the motor is fine (heads included), just have bugs to work out. It's expected after a project of this size.

I just noticed that the passenger side valve cover is off. That's great! Finding TDC of the compression stroke will be easier.

1) Rotate engine by hand (clockwise) until intake valve for #1 cylinder starts to open.
2) Keep rotating until #1 intake valve closes. Stop. You are now on the compression stroke.
3) Check balancer timing marks. Align balancer to pointer at 10* BTDC.
4) Check dizzy cap for #1 terminal location (the factory mark). Mark this position on the dizzy.
5) Install dizzy. Point rotor to mark corresponding to #1 terminal location.
6) Install cap.

Out of curiosity, do you have pedestal or stud mount rockers?

pedestal


You are the only thing between me and a full blown panic attack... :bang:
 
Hey Strype, don't worry. I think you are still good. Engine and heads should be fine. 67coupe is right on. Follow his instructions and the engine should be initially at the right timing point.

Sounds like you have a major fuel leak though. And you may have to change your oil again. At least it's not water in the oil.
 
pedestal


You are the only thing between me and a full blown panic attack... :bang:

Don't worry. When I had the engine in my 67 rebuilt, it was my first major engine work. We got the new motor to start (idle was terrible) but it would die everytime I shifted to Drive. After 5 days of trouble shooting and not making any progress, we had a wild idea. Called the machine shop and asked them about the firing order for the cam they installed. Idiots didn't tell me the cam required the HO/351 firing order. Swapped 4 plug wires, fired right up. To quote the machine shop, "you mean we didn't tell you."

Not to open up a can or worms..........

How did you set the lash during rocker install? The fact your friend couldn't not feel the compression with the spark plug out has me wondering......
 
Hey Strype, don't worry. I think you are still good. Engine and heads should be fine. 67coupe is right on. Follow his instructions and the engine should be initially at the right timing point.

Sounds like you have a major fuel leak though. And you may have to change your oil again. At least it's not water in the oil.

i hope u r right man

Not to open up a can or worms..........

How did you set the lash during rocker install? The fact your friend couldn't not feel the compression with the spark plug out has me wondering......

ummm... I didn't. If my buddies did I don't know how. I thought they were a direct bolt on.

eek
 
i hope u r right man



ummm... I didn't. If my buddies did I don't know how. I thought they were a direct bolt on.

eek

It would probably be best to verify that the rockers were adjusted correctly. I'll need to look up the link (I've only installed stud mount), but basically shims are required under each rocker. I believe the rocker bolt has to reach a certain torque within a specific degree of rotation. Too soon and you have too many shims. Too far and you don't have enough. Might want to ask you friends. I'm willing to bet a couple of the valves are hanging open and not sealing.
 
It would probably be best to verify that the rockers were adjusted correctly. I'll need to look up the link (I've only installed stud mount), but basically shims are required under each rocker. I believe the rocker bolt has to reach a certain torque within a specific degree of rotation. Too soon and you have too many shims. Too far and you don't have enough. Might want to ask you friends. I'm willing to bet a couple of the valves are hanging open and not sealing.

That would explain a lot if it is so...

I'm getting on the phone in a second after I look up the rocker arms. They were ford racing 1.6 and blue.
 
"screw it back in by hand until it stops then torque to 16-18 ft lbs. Use your torque wrench like the hands of a clock if you start with the wrench at 12 o'clock you should reach torque between 1/4 and 1 full turn or 3 o'clock and 12 o'clock."

Did he thread in by hand, then note how far the wrench rotates until hitting 20 lbs-ft?

No offense, but it's a little hard to believe all 16 rockers torqued correctly without any shims.