Noise help!

I have posted before about a noise in 74 CJ5 with a 232. I first thought it was the water pump and the consencus was to change it. I did but the noise is still there. I tried disconnecting the fan belt to rule out the alt, water pump and fan. Noise is still there with none of these turning. The noise is sort of a scraping/sqeauling noise and is definetly a rotating noise. It increases as the engine speed increases and sounds like it is coming from the timing cover. The engine runs strong and other than this noise it is perfect. Any ideas on diagnosing this?

Mike

 

timing sprocket bolt coming loose?

 

So in either case pull the timing cover and have a look?

 

My 258 had a grinding noise from the front and it was a worn out timing chain rubbing the cover. Ater I changed the timing set the noise is gone and I seem to have more power. I don't know if you can safely do this, but putting one end of a screwdriver or broomstick against the cover and the other end against your ear will let you hear if the noise is indeed from your timing chain.

 

For the $10 grab yourself a mechanics stethoscope, and be careful using it around moving parts.

 

....old mechanic taught me as a kid that a long shaft screwdriver or line up punch works pretty good as a diagnostic stethoscope in a pinch. Trick is finding the right place, you'll know when you find it.

 

The engine has like 35000 or so mileson the rebuild so is it likely the timing chain is shot?

Mike

 

harmonic balancer seperating and rubbing on the timing cover ?
only thing left turning if you took all the belts off

 

A short piece of garden hose also makes a good stethoscope.

 

I am planning to pull the fan and pulleys and harmonic blanacer off to theck all that out. And a new timing chain set is like 33 + the seal so not a big deal. But before I pull all this out and replace it is there anything else that anyone can think of?

Mike

 

So I had a closer look last night at the noise. I think I have found it. The harmonic balancer is rubbing against the timing cover. I lubed it a little with oil and the noise stopped. I had 2 harmonic balancers that came with the jeep and i am wondering if maybe I installed the wrong one or there is a spacer or something missing. The FSM doesn't seem to show a spacer. Any ideas?

Which one of these is correct for a 232?



Mike

 

Uhh...

Not meaning to be flip, but the one that fits is the right one. The AMC 6s are internally (neutral) balanced, so any pulley that's from a 232/242/258 should be ok. Don't know that you can call the crank pulley a 'balancer' as on other (externally balanced?) engines. Check that the belt grooves line up.

Generally the manual won't show you that much detail. They typically use archive pictures that demonstrate the repairs but may not be exactly the same as the year-model they apply to. The factory parts books will show much more detail, but there can be a lot of variation (even within years) in parts like this.

 

Timgr,
So with that line of thought it must be the other one I am hoping to get to it this week and swap them out. If not I am suire it'll self clearance soon enough.( I'm kidding)

mike

 

Darn noisy harmonica's! Get to be kinda loud when ya loose em inside your engine!R)

 

the vibration damper rubber may be coming apart
the outer portion of the balancer may be wobbling
causing the outer portion (or pulley) to make contact with the timing cover
the pulley should bolt to the vibration damper
the book shows a differnt part number for 1972, 1973 even 1974
unknown what the differences are
offset maybe ?