replaced heads/intake wont start

[350runner]

I set them off of the TDC rotating pushrods until there was a little drag and then 1/2 turn. Adjusted from TDC the 1 intake and exhaust 2,5,7 intake valves and 3,4,8 exhaust. Rotated 360 degrees and did 3,4,6,8 intake and 2,5,6,7 exhaust. the valves open and close when I rotate by hand. I might just do them all over again since I haven't tried that yet

Try just a quarter of a turn. That should get it right

 

[chengny]

Wouldn't it have to be on on TDC if I watch the #1 intake open and close and keep turning until back to 0 and both the #1 valves are closed? Anyway I have a bigger problem now While adjusting my valves again to make sure they weren't too tight I found the the #8 intake valve rocker is extremely loose while #1 is at tdc. When I rotate 360 degrees it is tight like it should be. So I pulled the pushrod thinking it might be bent and its not. Does this mean a flattened cam lobe?

Whatever pre-load you use (1/2 turn, 3/4 turn, etc) isn't really that critical. It's just to make sure that you have eliminated any lash.

Just be aware that this can only be done one time.

In other words, you can't set your pre-load and then go back around the rockers to "check your work".

If you have any doubts that you pre-loaded correctly, and want to do it again, you'll have to start fresh.

Back the rocker nuts off at least one full turn from where you were. Then walk away and wait an hour or so. That will allow the plunger spring to drive the plunger back up to the top of it's stroke.

Zero lash can only be determined when the plunger is at the very top. When it is at the top there should be no gap between the cup/socket and the circlip.

You must be registered for see images attach

Here is a trick you can use (if the intake manifold is off) to check your work without touching the rocker nuts again:

When you are all done setting pre-load rotate the engine and, one by one, check the gap between the top of the plunger and the bottom of the circlip - when the lifter is on the heel of the cam .

It should be about equal to the diameter of the wire that the circlip is made of. That is a sufficient pre-load and you'll never have to worry about bottoming out.

 

[1984c10]

Checked spark with plug to frame while cranking and it has a light orange spark. Thinking battery really low from trying to start. Now I definitely dont know why it wont start.

 

[1984c10]

Wouldn't it have to be on on TDC if I watch the #1 intake open and close and keep turning until back to 0 and both the #1 valves are closed? Anyway I have a bigger problem now While adjusting my valves again to make sure they weren't too tight I found the the #8 intake valve rocker is extremely loose while #1 is at tdc. When I rotate 360 degrees it is tight like it should be. So I pulled the pushrod thinking it might be bent and its not. Does this mean a flattened cam lobe?

Whatever pre-load you use (1/2 turn, 3/4 turn, etc) isn't really that critical. It's just to make sure that you have eliminated any lash.

Just be aware that this can only be done one time.

In other words, you can't set your pre-load and then go back around the rockers to "check your work".

If you have any doubts that you pre-loaded correctly, and want to do it again, you'll have to start fresh.

Back the rocker nuts off at least one full turn from where you were. Then walk away and wait an hour or so. That will allow the plunger spring to drive the plunger back up to the top of it's stroke.

Zero lash can only be determined when the plunger is at the very top. When it is at the top there should be no gap between the cup/socket and the circlip.

You must be registered for see images attach

Here is a trick you can use (if the intake manifold is off) to check your work without touching the rocker nuts again:

When you are all done setting pre-load rotate the engine and, one by one, check the gap between the top of the plunger and the bottom of the circlip - when the lifter is on the heel of the cam .

It should be about equal to the diameter of the wire that the circlip is made of. That is a sufficient pre-load and you'll never have to worry about bottoming out.

What I did was loosen all rockers and adjusted all over again as I did before. The intake is on and im trying to avoid having to take it off and get another gasket.

 

[1984c10]

So it has spark. The plugs smell like gas so I think theyre getting gas. When I turn the engine I feel compression from the spark plug holes so im lost on why it wont start

 

[89Suburban]

Checked spark with plug to frame while cranking and it has a light orange spark. Thinking battery really low from trying to start. Now I definitely dont know why it wont start.

Should be a blue spark. Replace the ignition module.

 

[1984c10]

Should be a blue spark. Replace the ignition module.

Is there anyway to verify its bad? I dont really want to just throw parts at it. It seemed to work fine before the swap

 

[chengny]

The Chevy HEI system requires at least 10.5 volts (on the primary side of the coil) in order to produce the 40,000 design volts at the plugs.

Check voltage at the primary side of the coil - that would be the pink wire coming from the harness that plugs into the distributor.

Use a meter and confirm that there is at least 11 volts available (one probe goes to the pink wire and the other goes to a good clean ground). First check it with the key in the run position but also check that the voltage does not drop below 10.5 volts when the starter is cranked.

As 89Suburban suggests, the spark should be be blue and bright.

There is no mistaking a healthy spark.

With a plug grounded to the block, crank the engine. A properly functioning ignition system will make an arc that jumps across the electrodes. It will be blue and also bright enough so as to be visible even in broad daylight.

You should also be able to hear an audible snap sound each time it fires.


The color "light orange" is a textbook description of a weak spark.

 

[chengny]

You must be registered for see images attach

Good reading on the HEI from Hemmings:

http://www.hemmings.com/mus/stories/2008/11/01/hmn_feature19.html

 

[1984c10]

The Chevy HEI system requires at least 10.5 volts (on the primary side of the coil) in order to produce the 40,000 design volts at the plugs.

Check voltage at the primary side of the coil - that would be the pink wire coming from the harness that plugs into the distributor.

Use a meter and confirm that there is at least 11 volts available (one probe goes to the pink wire and the other goes to a good clean ground). First check it with the key in the run position but also check that the voltage does not drop below 10.5 volts when the starter is cranked.

As 89Suburban suggests, the spark should be be blue and bright.

There is no mistaking a healthy spark.

With a plug grounded to the block, crank the engine. A properly functioning ignition system will make an arc that jumps across the electrodes. It will be blue and also bright enough so as to be visible even in broad daylight.

You should also be able to hear an audible snap sound each time it fires.


The color "light orange" is a textbook description of a weak spark.

Im going to charge my battery tmrw and check the spark again. I dont think there is 10.5v its pretty low from trying to start it for the past week

 

[1984c10]

You must be registered for see images attach

Good reading on the HEI from Hemmings:

http://www.hemmings.com/mus/stories/2008/11/01/hmn_feature19.html

Thank you. This is very helpful. Im going to save this

 

[89Suburban]

Man that is some good ****, thanks again.

 

[MrMarty51]

You are saying that You are " Rotating " the push rod.
That is wrong.
move the pushrod, up, towards the rocker arm then, down to the lifter. When there is no more end to end movement, You are then at " Zero Lash ".
I takes quite aa force to chang the " Feel of the Rotation " of the pushrod.
This experience is from the adjust of " solid lifters " in Harley engines.

 

[Jims86]

You are saying that You are " Rotating " the push rod.
That is wrong.
move the pushrod, up, towards the rocker arm then, down to the lifter. When there is no more end to end movement, You are then at " Zero Lash ".
I takes quite aa force to chang the " Feel of the Rotation " of the pushrod.
This experience is from the adjust of " solid lifters " in Harley engines.

Rotating the rod to gauge resistance when adjusting.

 

[MrMarty51]

Rotating the rod to gauge resistance when adjusting.

Point being, the lifters spring will have to be fully depressed and compressing against the solid components of the lifter before there would be a significant enough change, in rotating force, to be detectable with the fingers, at least with My fat O`l finners.
That is why the up to down movement is the best method. I think the Motors manual may even tell it like this. I will have to go looksee now just to be sure. LOL