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We bought a 09 HHR 2.4 LT with the VVT motor. With 122,000+ miles.
While driving it home (about 250 miles) stopped at a light and heard a light tapping noise. When accelerating the tapping eventually stopped. At the next light decelerating the tapping started again. Over the next week to 10 days of driving the tapping went to a knocking. To the point we stopped driving it completely. Ordered parts to do a timing chain. Upon removing the valve cover and seeing the cams were both 180 out at TDC. After reading multiple threads and watching countless videos to see if this was the case with any other motors and not finding any we moved forward with the timing chain replacement. Visual inspection did not have any scarring or damage to the piston heads or valves. Installed new timing chain making sure to only turn engine clockwise and never counter clockwise getting all marks lined up. Put engine back together and started it. It was noisier than before having a chirping, knocking and chatter noise. My husbands brain now fried and refusing to put more money into an unknown issue I am reaching out for advice.
While the engine was apart removed the oils pump to find it completely blocked with a clay like substance. (Cleaned out and reinstalled.)
The timing chain oiler not blocked to the point of no movement.
This substance was also found on the bolts for the cams. It was strange how the substance was formed in mounds in all bolts.
Cam lobes appeared to having been overheated as there was scars and marks.
Having just completed doing timing chain in our 08 panel with no problems cams and motor looked in much better condition. No scarring on cams.
Can anyone explain how having cams out 180 degrees, engine was running better than having cams in proper position?
Thank you in advance for your priceless knowledge
I took a short recording of what she sounds like the link is under photo The day after installing timing chain and adding brand new oil. Oil is milky. But no signs of oil in water or on oil dip stick. https://drive.google.com/file/d/1A9bihGFuDnZEpvNfjytlRmX79tK41YuH/view?usp=drivesdk
Last edited by Silvia-the-HHR; 03-19-2024 at 12:26 PM.
Reason: Adding audio and photo
Well to put it simply, you are mistaken. You probably had it at #1 TDC “exhaust stroke” at which the cams would be 180 out.
He used a compression gauge and knew which one was TDC. After all the videos and threads we have gone through we are 100% positive we have number 1 cylinder. Located on passenger side with all the pulleys. All 4 valves are closed on compression stroke.
Sure way to tell TDC isn’t with a compression gauge but a screwdriver in the #1 spark plug hole and watch the timing mark on the harmonic balancer when that screwdriver gets up top then starts going back down , that’s TDC. Now align the camshafts, to prevent valve to piston damage I turn the crankshaft so the keyway is at 3 o’clock. Now rotate the camshaft until the sprockets are in position 2 o’clock intake, and 10 o’clock exhaust, now turn the crankshaft counter clockwise, it’s ok as long as the chain isn’t installed, line up the keyway at 12 o’clock and that little dot at 5 o’clock. Install the chain
I'm sorry but you need a new engine. Your husband should have had a second opinion. Just from your story I could tell the knocking getting worse and worse was the crank and or rods and not a chain issue.
Oil pump blocked = seized bearings. I have no idea what "clay like substance" could be, maybe somebody poured some snake oil into it.
If all 3 timing marks on the sprockets line up with the colored links on the chain #1 is at TDC. Doesn't matter exhaust or intake; TDC is TDC.
I don't know what this recent fascination with exhaust or intake TDC is about. The computer knows when to fire the coils.
Since the cams only turn a half rotation per full rotation of the crank, then it is easy to understand.
Go from the engine being fully in time with all alignment marks lined up. Turn the crank 1 full turn. The cams will turn a half rotation or 180 degrees. This will be where #1 cylinder is now TDC but on the exhaust stroke.
03-18-2024, 11:32 AM
