My 22re is making a knocking or rattling sound whe i decelerate, or just let off the gass a little. Doesn't really make noise when accelerating, or under load. And it is worse when cold. It sounded liek your usual rod knock, but I replaced all the rod bearings and the sound got much better but still isn't gone... My only other guess is a piston slap, but could the timing chain be loose? or something else? any help would be nice...

 

I am not a total expert, but I will give you my humble 2c.

Does this happen at or around a certain RPM and does it occur when you keep it around that RPM, but disappears below and above that RPM?

Did you check your tolerances on the wrist pins when you were in there? You may want to locate where the noise is coming from, such as a particular piston, with a piece of hose or a stethoscope type tool.

I had a problem like the above about ten years ago with my 85 22RE. The noise was occurring at about 2600 rpm. I found that the wrist pin had worn into the third piston. I took it out and it was a little loose. I ended up replacing all four pistons so I wouldn't have to tear the engine down again.

Hope this helps, but please do not hesitate to hear other opinions.

 

the sound did seem to be coming from the pistons, as in the rings, but i haven't been able to pinpoint exactly where...

 

Sounds like the timing chain to me. When you let off the gas it is under less tension and will start slapping against the timing cover.
If it was piston slap, it would be there under load. Being under load is a big part of what makes them slap. Maybe replacing the rod bearings quieted down the noise they were making enough to make the engine sound better, but only clarified the noise coming from the chain.

 

now i just need to find some time to check that now... thanks

 

Good luck finding time to fix that lol...

 

x2 on the t-chain