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If it's knocking, I doubt it's the chain especially since you said both guides are still in place (it's usually more of a rattle). Is it more pronounced when it's cold and tapers off as it warms up? It's probably piston slap then (it seems to be quite common in the R series motors especially the low deck, '85 and up models). Don't wait too long to address it though, as the piston can and will, eventually come (catastrophically ) apart. Don't ask me how I know :shaking: Now, if it gets louder as it warms up (oil warms up and thins a bit) it could be a rod knock. If you catch it in time you might just be able to drop the pan and deal with it from below. Good luck!...........Hans

 

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Oh, and the chain guide on the drivers side has an obolong shaped top hole and a shouldered bolt so, it will move some (it pivots on the bottom bolt) is that the movement you're seeing? It's normal.......Hans

 

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I looked at some pictures of a stock guide and its an actual hole, on mine its like a half of a hole like it broke. (does that make sense?)Also i have no idea what piston slap is. I would just hate to do all this work for nothing!!!

Well, then it sounds like it's broken, however, with the rest of the guide still being there, the chain wouldn't be hitting the timing cover (although you should replace it) . The knock you're talking about (did you read my first post about when it does it?) might still be a rod bearing or piston slap (hope not, though )............Hans

 

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The engine has 120k on it. The oil presure seems to be ok on the gauge. The knocking noise is loud upon start up and after it warms up you can hear it at about 3000 rpms. Is there a way i can check to see if its a rod knock for sure?

Piston slap and a rod knock sound very similar. You said it's loudest when it's at start up (fairly cold) and quiets down once warmed up? I hate to say it but, that's exactly how mine (piston slap) started out. After awhile (many miles) mine got louder and I'd hear it all the time (really loud crawling under a pretty good load like in low range dragging the brake) then finally :nuke: You could identify which cylinder it is by pulling a plug cable while it's idiling and see if it quiets substantially, that'll be the one. It's not hard to drop the pan (solid axle?) and pull the rod cap of the suspected cylinder and inspect the bearing shell, then you'll know......Hans