Hope you can help

Peter J

Well-known member
Hey guys, help,
Awhile back, I was griping about a noisy valve and not being able to locate any clearance problems. I've messed around with all the valves and really had the clearances tight and still same click at same volumn.
Before I start pulling the head and pan, has anyone heard a broken ring sound like a valve?? I've had my sthethascope all over the engine/water pump etc. and sounds like #1 or #2 but it Runs great. I have NOT done a compression check though.
No threads really hit on the possiblity of broken ring noise...I checked.
Thanks!
Pete
 
Seems like a valve train noise would be a slow click (half the r.p.m.'s), where a piston related noise would be fast, matching the actual engine revelutions. What does a boogered up cam gear sound like? Messed up teeth would be at the front of the engine like your noise and could be at half speed.
 
How about if you rotate the suspected piston/cyl to the bottom and look thru the spark plug hole to look for abnormal wear/gouging on the cyl wall or a compression ck. How about a cracked spring that applies pressure to the front of the cam??
Paul in CT
 
PeterJ,
I've had good success LOCALIZING noises with a cheap stethascope without the probe, just use the open hose. With the probe, sometimes the sounds transmit & are hard to localize.
Used that way, you can also find & locate vacuum leaks in a jiffy! It'll scream like a BANSHEE! Bill W.
 
I had a "clicking" noise up front. It was consistent. It turned out to be the generator pulley. It was a two piece pulley that had 4 rivets to hold the two pieces together. The rivets were loose. Found this by taking the fan belt off and starting the engine.
 
In high school I had a 54 Chevy with worn ring lands and broken rings on one piston. It didn't make a sound, but I could feel the loss of power on one cylinder.

If you have a cam gear with an aluminum center check there for noise and loosness.

BTW, I knew they were broken rings because I removed that piston and changed the rings. Three days later I learned that I should have changed the piston at the same time, because the new rings broke again.
 
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Let's see. Used the stethascope(sp) an it definately #'s 1 or 2. Fiber cam gear and no noise in that area. Fanbelt off and still clicks. I've got about 40 miles on since installation. Stock B engine, new valves/guides and rings. Like I mentioned I'm at my wits end and need to know if a broken ring could do it. I think all other variables have been explored. Valve cover has been off 5 times looking for this sucker!:mad:
 
I run a B engine with a click like a valve clearance proble--middle of the engine. I'm convinced it's too much clearance on the center cam bearing. Engine runs great, clicking almost goes away after the engine gets good and warm.
 
Are you running the "B" fuel pump? (might be a suspect)
If it were mine, I might add 1/2 to maybe 1 bottle of STP to see if the viscosity change might affect the noise. No, I'm NOT a proponent of additives! I might also just drive it lovingly and see what develops. Bill W.
 
Have you tried shorting the plugs for #1 and #2 to see if the noise changed?

It's better to short the plugs rather than pull the leads away, as the coil can short when the spark isn't sent to ground.
 
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I've shorted the plugs at different speeds. Both have a good rpm drop. The noise seems to get louder when warm. I did think I noticed the noise getting a little erattic today when I got up around 40 but can't be sure. I've also dosed the gas with liberal amounts of MMO. #1 cylinder did have some scoring when I put it together but didn't go all the way up and I honed it down pretty well.
 
This one started out sounding like a valve clicking. You could be on to something. This one ended having more brass in it than cast iron,LOL.
 

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Peter, any chance it might be a loose valve seat? We had one like that on Dad's 30 P/U, chased a click for a day, then pulled the head. Every thing looked OK so I spun it over, then No. 2 Ex. Popped up wearing the seat insert. then it fell back to the block and we had our noise.
 
I've shorted the plugs at different speeds. Both have a good rpm drop. The noise seems to get louder when warm. I did think I noticed the noise getting a little erattic today when I got up around 40 but can't be sure. I've also dosed the gas with liberal amounts of MMO. #1 cylinder did have some scoring when I put it together but didn't go all the way up and I honed it down pretty well.

Any idea what your piston clearance is after honing? Piston slap tends to have more of a clatter type noise but tough to say for sure. I've also seen "tickers" caused by subtly bent connecting rods.
 
I didn't check any clearance except the rings. It definately sounds metallic. No valve inserts so that's not it. James, that's ugly! Ive tried to check out the bore through the spark plug hole but couldn't get enough light down there. I'm going to test compression today. Hopefully I'll get a drop. I'll report back on my findings. I'm real uncomfortable with the "drive it until it breaks" theory.
Pete
 
James, with the snap ring still in place, how do you explain all that damage on that end of the piston?
Did a broken end of the other snap ring travel through the hollow wrist pin and get jammed in that end?
 
I didn't check any clearance except the rings. It definately sounds metallic. No valve inserts so that's not it. James, that's ugly! Ive tried to check out the bore through the spark plug hole but couldn't get enough light down there. I'm going to test compression today. Hopefully I'll get a drop. I'll report back on my findings. I'm real uncomfortable with the "drive it until it breaks" theory.
Pete

When I worked at the GM dealership I used to make bore lights by connecting thin wires (such as used for earphones) to a small side marker bulb. This would easily fit down the plug holes on Vega engines to check for scored cylinder walls.
 
Mine has a tick that comes from the oil pump, still works fine and someday I will tear it apart and rebuild it.

Mike
 
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