# 1981 210 Piston rings.



## Robvert210 (May 14, 2011)

Hey guys! I'm back again with another question. My car has been making a rattling/knocking noise while I drive it, as well as smoke. While we checked under the hood, we deduced that the noise was around the area of where the engine is, but more mid-level rather than on top of the engine or below it. My friend's uncle took a look and said that the car could be suffering from "blow by/blowback" and to check the compression to make sure that the piston rings are fine. I wanted to start preparing in case this is the problem, so I was browsing for piston rings, but I can't find any online. Is this going to be a job that I'll have to get a mechanic to do, or do any of you know of any websites that might carry some? Also, if you could put your word in as to what might be causing the problem, feel free to chime in. A little side note, that rattling sound seems to get louder the more I accelerate. If you need any more information on my part, just let me know.


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## SPEEDO (Jun 9, 2003)

Have you done a compression test? are you sure its not a rod knocking?


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## smj999smj (Jan 1, 2006)

My thoughts exactly! Also, if you are going to be putting piston rings in a 30-year old engine, you might as well be ready to rebuild the engine or look into the availability of remanufactured engine options. The cylinder walls will need to be measured and honed or even possibly bored. You gotta figure it'll be time for a new timing chain kit and rod & main bearings, as well. You see where this is leading? So, compression (and I would recommend a cylinder leakdown test, as well) would be the first thing to do. A blown head gasket could also exhibit these same symptoms, and if blown between the cylinders, would definitely cause a knocking type noise. Make sure all of the plugs are removed before you do the compression test.


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## Robvert210 (May 14, 2011)

We did the compression test, but I think that we may have done it wrong since we didn't remove all of the spark plugs haha. The first cylinder and the last one were fine. (The first at 180 and the last one at 200[minimum in my service manual was 170 and standard was 190]) While the second cylinder came in at 150 and the third at a very low 120. We also noticed that the knocking was getting louder.


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## smj999smj (Jan 1, 2006)

You need to remove all of the spark plugs because if the head gasket is blown between to cylinders, the adjacent cylinder, if the spark plug is still installed, can push compression into the cylinder being test and give you false readings. Also, during a compression test, a battery charger should be installed and the throttle plate wedged open.


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