Knocking/tapping sound from front of engine?

[rsm688]

Okay guys well yesterday when my 06 H3 3.5L with 138k miles was sitting their idling I heard a popping/knocking noise coming from the top front of my motor. Popped the hood and changed the oil today and it is still there. It feels like I can actually feel it in the little black manifold cover where you fill the oil level. Almost sounds a little more like pop than a knock. Any ideas on what this might could be? I'm hoping maybe something like rocker arms or springs and nothing major. Anyone else had a sound like this before?



Thanks,
Spencer

 

[alrock]

Haven't had anything like this but hopefully the guys with more engine experience will chime in.

 

[Happy Hummer]

Possibly cam actuator screens missing? Possibly timing chain tensioner? Possibly oil not getting into upper reaches of engine because of blockage?

I'd start with a compression test. Change cam shaft actuator and add a quart of transmission fluid to oil and drive for a few miles then drain and put Mobile one in. Don't forget to replace filter. Jmho

 

[speedy]

Might be as simple as the serpentine belt tensioner or idler pulley.

 

[rsm688]

Possibly cam actuator screens missing? Possibly timing chain tensioner? Possibly oil not getting into upper reaches of engine because of blockage?

I'd start with a compression test. Change cam shaft actuator and add a quart of transmission fluid to oil and drive for a few miles then drain and put Mobile one in. Don't forget to replace filter. Jmho

Thanks a ton guys. Happy Hummer, how intensive is replacing the cam shaft actuator? I'm very mechanically inclined but have not done much internal engine work strictly because I have been lucky with most all my vehicles and never had to other than replacing a cam or two in some older trucks.

I'll check my tensioner and pulleys and all well.


Thanks a ton guys

 

[Happy Hummer]

One bolt an 1/2 hour of your time. Check to see if screens are in it, if not replace.

 

[tgomes78]

I had the same thing happened to my 06 about a year ago. It was the timing belt tensioner


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[Happy Hummer]

OK there is a second timing reference. Of course it could be the belt tension-er on the front of the engine too!

 

[e0308jr]

I had the same thing, it ended up being the belt tensioner and the water pump was bad

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