[TedRamAirII]

Originally Posted by shaker455

Ted,
You ever build an engine before?

I'm actually asking the OP is that's indeed what he did?

If the cam is not installed correctly his valve timing will be off and no compression is possible....or something will kick back...

My point is that you can set the cam at 12 or 6 with the crank at 12 What difference does it make to compression? NONE. The crank doesnt care, it just spins and the cam marks line up every other crank revolution. The cam timing just dictates when the cylinder is at one of the 4 strokes. I suspect the cam timing is a mile off.

[shaker455]

Originally Posted by TedRamAirII

My point is I suspect the cam timing is a mile off.

I agree to that.

[TedRamAirII]

Originally Posted by c5farmer

Sounds like the timing chain is not installed correctly. Agree with shaker455, the timing marks need to be 12 oclock on the crank gear and 6 oclock on the cam gear.

6 OR 12, NO DIFFERENCE. If the crank is 12 and the cam is 6, then you have #6 cylinder firing at that point. but that wont alter compression. If compression is off, the cam timing is WAY off.

[TedRamAirII]

Which Cloyes chain set was installed?

[NeighborsComplaint]

If the cam timing is off 180 and the distributor not clocked to match, it should backfire like a mofo. My guess is the valves are all open. the lifters were not pumped up and over-adjusted.

The easiest way to check for compression is unplug the distributor or pull the cap, pull the #1 plug and hold your finger tightly over the hole as someone cranks the motor. You will feel the compression build and push your finger off the hole.

[gtofreek]

Are you sure you used the correct timing mark for the keyway used? The timing mark for each appropriate key slot should be between 2 and 3 teeth to the left of the key slot. In other words, the key slot, or crank key should be at approximately 1-1:30 position when it's correct timing mark is at 12 o'clock.

I also agree one should use the 12/6 o'clock method because the timing marks are closer to each other, therefore making it easier to align them correctly. When they are at 12/12, it is much easier to be off 1 or 2 teeth.

Valves have to be open at TDC to cause no compression. A breach in the head gasket between cylinders would still cause compression, it will just be low, like 30 lbs. or so in both cylinders. Rings not sealing will also still build compression, so that eliminates that as a cause. The only other thing to cause no compression, would be a hole in the piston, but since it has never fired, and I doubt anyone would be dumb enough to install a piston with a hole in it, that pretty much eliminates that too. So that only leaves, cam timing or rocker adjustment. The blowing back up the intake confirms that. Or a terrible valve job, but it would have to be EXTREMELY BAD to cause no compression.

[oville]

Found receipt cloyes 9-3112. There are plus minus 4 deg keyways so maybe I screwed that up. Plus think OF can is plus 4 deg can advance so maybe that adds up to way off. Loosened up the rockers and put air pressure to cyl and it holds. Not happy but guess have to pull the front cover and see what's up.

[gtofreek]

Also, most of those +4° cam adv/ret key slots that I have checked, are 4° at the cam, which equates to 8° at the crank. When degreeing a cam, you are degreeing off of the crank, so 8° is a lot to move the cam one way on another. Most Comp cams, and Lunati cams are ground with the advance built into them, so if all is perfect and ideal, then theoretically, you should be able to use the straight up/zero advance key slot and timing mark to set the cam timing where it should be. That's a good place to start. Unfortunately, theoretics have been proven to be wrong in the world of production engines, many times.

[oville]

Well was at 12 O'Clock on both, but (ironically) was in the retard keyway. So with the dot straight up the actual keyway was down at about 6 O'Clock.

[grivera]

While you have it apart, do yourself a favor and degree it. Even if Dave told you to install it "straight up" doesn't negate the fact it needs to be degree'd-in.

[72LuxuryLeMansLa.]

Straight up to me means install with degree wheel so that the intake valve closes exactly when the cam card says it should!

[johnta1]

If you are thinking it's off because the 'dot' on cam is at the top when the 'dot' is at the top on the crank gear, that won't matter.

What is needed to be correct is that the crank gear keyway with the dot, or square dot or triangle (or whatever it is) that you use the same mark on the gear by the teeth.

Example:
Using the triangle by the keyway as where the gear is put on the crank, the triangle below the tooth on the gear will need to be pointing up and aligned with the 'dot' on the cam gear.

I would say you are using one of the other keyways on the gear and using the 'dot' for the aligning of the gears.

[grivera]

Originally Posted by 72LuxuryLeMansLa.

Straight up to me means install with degree wheel so that the intake valve closes exactly when the cam card says it should!

yep- exactly what I meant to convey

[gtofreek]

Originally Posted by 72LuxuryLeMansLa.

Straight up to me means install with degree wheel so that the intake valve closes exactly when the cam card says it should!

Technically, "straight up" means putting the intake centerline the same as the lobe separation angle. So, if the cam is ground on a 112° LSA, installing it "straight up" would be putting the ICL at 112°. With most cams in a Pontiac, doing this will make it be sluggish. Advancing it 4° would put the ICL at 108°, on a cam ground on a 112° LSA. Comp and Lunati, and others, try to grind that advance in if that is where they want it installed. Trying to make it more foolproof. Unfortunately, there are too many variables in play to always insure that.

[HWYSTR455]

Originally Posted by gtofreek

I also agree one should use the 12/6 o'clock method because the timing marks are closer to each other, therefore making it easier to align them correctly. When they are at 12/12, it is much easier to be off 1 or 2 teeth.

This is the reason to use 12 & 6. One tooth off is very easy to occur at 12 & 12.

Just to air things out, explain two things:

1) How did you adjust the valves/rockers? Outline the process you used.

2) How did you determine TDC compression stroke on #1?

Once you answer these, maybe something will become more obvious.

If you were in the retard keyway, it would have an effect, but not sure that much. It should still have started.

Comp is pretty good about the custom grinds, and usually they zero out pretty well. The OF is a custom grind. Also, Cloyes are pretty good about being accurate. (But it's still good to check)

.

[rtanner]

i am continually amazed at the shear lack of basic ability alot of people on this board have, wow

[torqhead]

Originally Posted by rtanner

i am continually amazed at the shear lack of basic ability alot of people on this board have, wow

Well that was really helpful, I can now go out and fix my car!!!

[torqhead]

Oville, I would recommend going to the basics before opening up the motor. Do basic compression check even with your finger as suggested. Validate you actually have spark to at least one of the plugs and then ensure you've got #1 cylinder at TDC and the rotor of the distributor pointed at #1 plug wire. Even a motor with little compression will fire with the basics done.

[GOAT WHORE]

Originally Posted by rtanner

i am continually amazed at the shear lack of basic ability alot of people on this board have, wow

Uncalled for rtanner. With that attitude we wouldn't need this street section as we would all know everything.

[77 TRASHCAN]

Originally Posted by GOAT WHORE

Uncalled for rtanner. With that attitude we wouldn't need this street section as we would all know everything.

We'll all let him pull his foot out of his mouth...