Cam Chain Jumped Time
#1
Cam Chain Jumped Time
New to forum. My daughter has a 2007 HHR with 70,000 miles on the 2.2 engine. I live in Western KY, she lives in CO. She has a problem with the cam chain jumping time. From what her "mechanic" tells her, they want to replace the whole engine !!! I know a little about cars and engines, mostly old school. Sounds like someone needs to remove the head and further assess the damage. We know one rocker is broken, but what is the likelihood of damage to a piston or worse. It's hard to give advice to someone 1000 miles away. Anyone know an honest place in Monument or Colorado Springs that can handle this?
Can't figure out how a cam chain or tensioners/guides cam be defective in only 70,000 miles.
Thanks in advance for any help.
Can't figure out how a cam chain or tensioners/guides cam be defective in only 70,000 miles.
Thanks in advance for any help.
#3
Welcome to the forum.
There have been a couple timing chain/tensioners/guide failures talked about on this forum. Only a couple failures of the thousands and thousands that were made. Sounds like her's was either a freak thing or maybe a maintenance issue.
(i.e. regular oil and filter change)
Now. A broken rocker arm brings up another problem. Sounds like maybe with the chain failure, it caused piston to valve contact. If so, then you could very well be looking at a new engine.
There have been a couple timing chain/tensioners/guide failures talked about on this forum. Only a couple failures of the thousands and thousands that were made. Sounds like her's was either a freak thing or maybe a maintenance issue.
(i.e. regular oil and filter change)
Now. A broken rocker arm brings up another problem. Sounds like maybe with the chain failure, it caused piston to valve contact. If so, then you could very well be looking at a new engine.
#4
Thanks for the comments. I preach that changing the oil and filter every three to four thousand miles is key to life of the whole car. She's been pretty good at maintaining her car. I can't see why the cam chain would jump in the first place.
Looks like a valve and piston may have gotten together. She sent a picture of a lifter (I think) that was broken. However, even if they have to replace a piston (providing no cylinder wall damage) it's cheaper than a whole engine. So far, all that has been done is remove the cam cover and one damaged spark plug. Does not look real good.
Wish us luck!
Hopefully she will find someone reliable to diagnose this thing for us.
Looks like a valve and piston may have gotten together. She sent a picture of a lifter (I think) that was broken. However, even if they have to replace a piston (providing no cylinder wall damage) it's cheaper than a whole engine. So far, all that has been done is remove the cam cover and one damaged spark plug. Does not look real good.
Wish us luck!
Hopefully she will find someone reliable to diagnose this thing for us.
#5
The easy way to get the timing chain to jump a tooth is to rotate the crankshaft counterclockwise (lefty, in the digital clock world). Just sayin'.
I am not sure what is meant by "a broken rocker". The part you are looking at may actually be the chain tensioner, it can be removed without removing a camshaft.
The tensioners and guides are plastic or nylon and do wear.
Somebody has beat the S--- out of the engine in this car, I wonder about the trans.
Pulling the head is going to cost pretty close to putting a used engine in, that may be what the mechanic is saying. Figure $2000 for a used engine installed.
It is even harder to diagnose an engine over the internets.
I am not sure what is meant by "a broken rocker". The part you are looking at may actually be the chain tensioner, it can be removed without removing a camshaft.
The tensioners and guides are plastic or nylon and do wear.
Somebody has beat the S--- out of the engine in this car, I wonder about the trans.
Pulling the head is going to cost pretty close to putting a used engine in, that may be what the mechanic is saying. Figure $2000 for a used engine installed.
It is even harder to diagnose an engine over the internets.
#6
I hear that !!! I guess I'm just looking for a reason this happened. She bought her HHR used, so no tellin'. She sent a picture of the broken hydraulic rocker tensioner(?). And there is also a beat up spark plug. That pretty much tells the whole story. Somehow the cam jumped time. Got off enough for a valve to hit a piston. I suspect she continued to drive until it quit.
If it were here, I'd pull the engine and probably sleeve the damaged cylinder (if needed). Then find a used head, do a valve job and have her back on the road for less than a$1000. But, you're probably right about a used engine for around $2000.
Thanks again for the comments. I guess misery loves company.
If it were here, I'd pull the engine and probably sleeve the damaged cylinder (if needed). Then find a used head, do a valve job and have her back on the road for less than a$1000. But, you're probably right about a used engine for around $2000.
Thanks again for the comments. I guess misery loves company.
#7
Unfortunate, another 2.2 with timing chain/tensioner issues. Was this a 2007 or 2008?
Was there any rattling/tapping noise on cold starts for a period before failure?
If you can see damage inside an engine, with tighter tolerances these days, they usually recommend replacement. Debris from that damage will cause excess wear and could block small oil passages.
Was there any rattling/tapping noise on cold starts for a period before failure?
If you can see damage inside an engine, with tighter tolerances these days, they usually recommend replacement. Debris from that damage will cause excess wear and could block small oil passages.
#8
Mr Wilson-
Bummer about the 2007 2.2L
Ecotec engine is an 'interference' engine, with 16 valves & DOHC.
Any contact made, it will be at least 2 valves. & For it to break a 'cam follower' (finger) have to assume valves did meet at least one piston.
Good Luck on this one..
Bummer about the 2007 2.2L
Ecotec engine is an 'interference' engine, with 16 valves & DOHC.
Any contact made, it will be at least 2 valves. & For it to break a 'cam follower' (finger) have to assume valves did meet at least one piston.
Good Luck on this one..
#9
Okay, we picked up the Daughter's HHR this morning. Complete with a replacement used engine (and clutch - seemed prudent).
Question, at 68,000 miles on this (new) used engine, what is the likelyhood of this cam chain problem happening again?
Question, at 68,000 miles on this (new) used engine, what is the likelyhood of this cam chain problem happening again?
#10
If the engine is out of the car it is relatively easy to replace the guides, they are only nylon. The kits come with the oil nozzle. The key is to not turn the crankshaft. A $100 or so might be good insurance.