[chidog]

And how are they running with the spring replacement or stretching it?

 

[chidog]

I have read about some that did not work with the spring changed or stretched. I think that could be because it was allowed to do the rattle for too long and may have worn too much around the hole or ?
I guess it is a hit and miss on what the spring tension should actually be to properly do the job. When you all have removed the original spring about how far does it uncompress?

 

[chidog]

What I meant about uncompress is, when the cover is removed how much spring is sticking out?

 

[chidog]

Concerned ? Essentially it is acting like an impact wrench of sorts each time it does that. It likely does not hurt the actuator when rattling, but it does impart that back and forth action to the timing chain.
I have read cases where at some point in time down the road, that some have had timing chain stretch and or failure as in valves hitting pistons etc. I'm sure it doesn't do the timing chain any good at all.
And yes many folks say they have gone like that for years.
The reason for the rattle other than not being locked because of that pin, is because its waiting for oil pressure, the tensioner is also waiting for oil pressure at the time, so there is a chance of chain slack that could cause it to jump, then of course there is those seconds of added high stress to components of the timing chain. Just wanted to explain the concern.

 

[chidog]

Just note that even if you had it fixed, the problem doesn't resolve with a new actuator. Considering the car is almost a decade old, I would just live with it. Yeah, the sound might be embarrassing on the intial startup... especially in a parking lot. Mine still does it from time to time, but recently with the heatwave this summer, it hasn't rattle much since March.

Why does that problem occur on a year or generation specific? Wifes 2009 150 ish K miles, no problem, its never had it changed so must be factory original. I'd like to know what they are doing so different now? Yeah if your not a diy person I agree leave it.

 

[chidog]

Nice pictures etc. Now I'd really like to know where to buy or get the spring at. And the dimensions of it? I wish there where photos of the springs and such.

 

[chidog]

Thank you all for the info.

 

[chidog]

I don't like to send a credit card number into a dark hole that will not put their business address nor their phone number. There are no details of what is in the kit either. Does it include the bolts ?
And why only a listing for the newer crv's some older ones can have the problems as well.

 

[chidog]

The valves are held closed by a strong spring. When a cam lobe pushes the rocker and the valve open the pressure on the chain rises and then as the lobe passes over top center the tension begins to drop and the lobe actually pushes the cam and the chain in the opposite direction. If there is a slight amount of looseness or "play" the cam will turn slightly in the opposite direction. If you are turning it slowly by hand you can see this effect. Another factor that increases this effect is the variable valve timing sprocket. When there is no oil pressure the variable sprocket can move over a wide range if the locking pin is not engaged. This locking pin in the variable valve timing spocket prevents the cam from turning forward or backward when there is no oil pressure when starting the engine. This is especially noticeable when the oil drains down out of the upper valve train after sitting all night. This is the reason we hear the dreaded loud rattle after an overnight startup. With no oil in the variable chambers the cam jumps backward and forward until oil pressure fills the chambers and holds the cam in its correct timing position. This noise is intermittent depending whether or not the pin locked and how long it has been since the engine was stopped and also temperature and the position of the cam when it was stopped.
Also worth noting is that this "rattle" does not have any associated damage and the engine runs normally as soon as it develops oil pressure and the rattle stops.
Some people claim that turning the key to the on position and waiting for 10 or 15 seconds will prevent the noise when starting the engine. This will not help if the locking pin is not engaged and the oil in the VTC sprocket has drained out. The engine will need to run for a short time while oil under pressure fills the chambers in the VTC sprocket. This short time is when the noise is heard.

You mentioned this. "If there is a slight amount of looseness or "play" the cam will turn slightly in the opposite direction", this is a vibratory shock loading on the timing chain and tensioner, amplified by the extra slop from the non locking actuator, so there is a possibility of " associated damage" given enough time. How much time? And actually after a quick study, some folks have had timing chain slippage that could have been from letting this go long term.