Hello all!

I have a 2007 HHR with low compression on cylinder 3. I brought it in to be diagnosed after replacing the plugs and the fuel injector and found out the piston ring needs to be replaced. I am wonder if anyone has done this themselves and how difficult it is to do? I understand this probably isn't a simple project. I'm trying to avoid paying the extra labor costs associated with a complete rebuild (they won't do just the rings and support future problems) or a used engine (which is a gamble).

 

Installing new piston rings is a very involved procedure. You will need to almost fully disassemble the entire engine to replace piston rings.

The head will have to be removed and the oil pan so that you can unbolt the piston rods from the crank and slide the piston and rod up and out of the engine to replace the rings.

To get the head off you will have to remove the timing chain, intake manifold and exhaust manifold and everything associated with those items.

When replacing rings it is wise to also replace the bearings or you might be tearing into the motor sooner than you would have if you just left it alone. Bearings need to be gauged for clearance and are likely to need a slightly different size with each tear down since there is wear associated bearings and the crank.

Hopefully you see by now that doing all this for one piston is silly. You have to do 99% of the same labor to do 1 piston as you would if you did all 4.

 

I actually did that back in the day on a much simpler vehicle (1964 Ford Falcon). It was a 'beater'. Even so, I drove it for another couple of years until I sold it. That being said, I wouldn't do that to any modern vehicle.

 

Tearing down the engine to get to the rings is the hardest part, they are giving you the best solution. You don't want another part failing a couple months later.
Replacing with a used motor can be a good alternative depending on cost and mileage/condition.
I have done both on other vehicles and found they often last about the same time.

 

Thanks for the tips all! It sounds pretty involved as I thought it would. The top parts shouldn't be too terrible in theory. How bad is the timing chain to deal with on these?

 

I did a little looking around and now see that a complete rebuild kit will cost right around 700.00 plus or minus up to 100 dollars.

When the kid put the rod out the bottom of my engine I went with southwest engines and got one for around 1300.00. It cost me around another grand to have it put in since complete engine swaps are no longer in my repertoire.

Many years ago a friend and I were car pooling to electronics school in his inline 6 cylinder AMC Eagle. I had a '74 Ford LTD with the 427 V8. His car used less than half the gas mine did so we were mostly driving it.

One day on our way home from school his engine ate a valve and the valve head actually came out the exhaust. It smoked like all get out and ran terribly but we made it home.

The piston had valve head shaped holes in it and the combustion chamber had valve head shaped dents all over it. The cylinder walls were scored and badly burned looking.

We decided the head and that piston were toast and went to the local junk yard and found another similar Eagle to get a head off of. We also took just one piston from the same cylinder as he had bad.

When we got home I installed the 'new' piston with the bearing it had had in it in the other engine and slapped the head on again. I did have a ridge reamer and had taken the time to replace the valve seals in the used head and since I had the rocker arms off I lapped the valves a quick one. While I had the slug out of the cylinder I used my 1/2" drill and an abrasive covered sponge to break up the scoring in that cylinder then turned the crank and did the same on the others as far as it would reach without removing the pistons.

We were both pretty shocked when the engine fired right up. Of course it smoked really bad but running engines with holes in one piston will load your exhaust with oil pretty badly so it was to be expected.

He drove the car all that summer while trying to sell it but no one wanted to buy it, I think he was a little to honest and told folks it had pooped a valve head out the exhaust at one time.

We continued to drive it to school the next year too. After graduation he got a job out east somewhere like maybe Pennsylvania or Maine. He bought a Suburban and a utility trailer then rented a U haul trailer. He was able to jam most of his stuff in the Suburban and his trailer then stuffed the rest into the U Haul and his wife and kids in the AMC. Yes, the AMC pulled the U Haul all the way out there.

He called a few days later to say he had made it just fine and to say the AMC had barely used any oil on the trip.

I never dreamed that it would last that well. Guess its like dad used to say "Sometimes even a blind hog turns up a truffle" which means I got lucky.