I'm all set to install the camshaft and timing chain, but I'm concerned about the decomp weight. While viewing the sprocket end of the camshaft, cam lobes at 7 and 11 o'clock so that the weight is rotating upward against gravity, the action is nice. It feels just right.
Turn the camshaft 180*, lobes are at 1 and 5 o'clock so that the weight is wanting to drop by gravity. The spring can hold the weight in the retracted position, by only just. Move the weight down a bit and it stays there. Move it full travel and release and it does spring back. Is it typical to be just barely OK when fighting gravity?
The spring has a little more than half a turn preload when it is installed. I doubt more preload would help. A full turn extra would wrap the sring tight enough against the shaft it might cause extra drag and not provide extra force.
With the camshaft sitting in the head, I can flick the sprocket around fast enough to get a clack out of the weight as it momentarily gets to full travel. I'm sure I'm getting it to spin much faster than typical cranking speeds. At cranking speeds I believe the weight will stay retracted and do it's job.
When the engine is shut off, I think it tends to stop rotating after the intake valves close and before the exhaust valves open. In this range the weight would stay retracted OK. The weight just seems very sleepy when the camshaft is in a particular location.
I think the engine will always rotate through a point where the weight will retract. Since the spring can hold it in the retracted position, I believe the auto decomp will do it's job.
Thoughts?
Turn the camshaft 180*, lobes are at 1 and 5 o'clock so that the weight is wanting to drop by gravity. The spring can hold the weight in the retracted position, by only just. Move the weight down a bit and it stays there. Move it full travel and release and it does spring back. Is it typical to be just barely OK when fighting gravity?
The spring has a little more than half a turn preload when it is installed. I doubt more preload would help. A full turn extra would wrap the sring tight enough against the shaft it might cause extra drag and not provide extra force.
With the camshaft sitting in the head, I can flick the sprocket around fast enough to get a clack out of the weight as it momentarily gets to full travel. I'm sure I'm getting it to spin much faster than typical cranking speeds. At cranking speeds I believe the weight will stay retracted and do it's job.
When the engine is shut off, I think it tends to stop rotating after the intake valves close and before the exhaust valves open. In this range the weight would stay retracted OK. The weight just seems very sleepy when the camshaft is in a particular location.
I think the engine will always rotate through a point where the weight will retract. Since the spring can hold it in the retracted position, I believe the auto decomp will do it's job.
Thoughts?
