A lot of folks on "Bob is the Oil Guy" or BITOG recommend Auto-Rx over Seafoam. Check it out. Never used it myself but sounds interesting.
www.auto-rx.com

 

I found the Marvel Mystery Oil , but not the Seafoam around here. Says you should not overfill the crankcase. Does that mean I need to drain a quart of oil before I put the MMO in, or is it Okay for an LT1 to be a quart overfull (on my Cosworth, it is recommended to overfill for auto-X)? If I do need to drain, I assume the only method is by removing the drain plug, letting out a bit, and popping the plug back in after a quart...

 

I would take the belt off just to make sure it was not a belt driven noise first. Nice videos

 

So the MMO has been in a few weeks. I drove it for at least a week, but my jaunt to work is quick (6 miles) and it was cold out. One day in traffic max oil temp reached only 204 degrees F. Oil pressure on cold startup is 60psi, drops down to 20psi at idle when warmer, seems pretty normal. I was worried about the looseness of the rockers and pushrods, even just after being run, so I pulled the valve covers (gaskets were starting to leak anyway). Many pushrods seemed loose but took just 1/8 od a turn or less to tighten them up, then I applied 1 full turn while on base circle as per Chevy manual. They bled down from there after several hours. I purchased some oil deflecting clips, and ran it, and was going to adjust it hot, but got sidelined when I noticed much less oil coming out of #3 exhaust. I pondered that for a few days, an decided to leave it - and elected to not mess with the valves more, as it seemes to be running fine. No codes ever.

I used my new stethoscope all over the engine. Noise is coming mostly from the front. The sound is distinct from the water pump , where it has more of a ring to the sound - more musical and clear, but definitely a regular tapping/ticking. (I previously replaced original WP with a GM unit at 90K). I can also hear the sound from behind the water pump on the front timing cover, and also through the intake manifold, but it is more dulled. I was chicken to try and put the stethoscope on the (original) Opti. The farther I move aft on the intake the quieter it is. No one valve or lifter or rocker appears to sound different from the others. All injectors sound fine. All the exhaust gaskets and manifolds are fine. Again, I can hear the sound more on the front exhaust manifolds than the others, and also better on the front of the heads, as opposed to the rear. I took the belt off, and replaced the tensioner and idler pulleys that were noisy. Aft alternator bearing is noisy too, but I'll wait to see on that one.

So, where to go from here?
1) change to heavier oil (from 5W30 to ??W???), as I first noticed this with the oil change
2) drain coolant, pull water pump, inspect
3) water pump gear
4) timing chain

Thoughts?

Ken

 

allow more time for the MMO to work-it is amazing stuff. Glad you did not go the Seafoam in thecrankcase route-IMO that is way too strong of a solvent to be in the oil for more than idle speed.
BTW my 95 LT1 can sound like a sewing machine when just starting- it adds to the character of the car. I always use 5-30 with 52K on it

 

I adjust my valves to where they stop clicking and give them a 1/2 turn and install a can of JB Justice Brothers Engine Tune up and it usualy quiets the lifters down .I also put Mobil one high milage oil in the oil.

 

Well,

I finally got around to seeing what the problem was. This picture says it all I think.

http://forums.corvetteforum.com/phot...0/ppuser/31369

The water pump drive gear has lost 2 teeth.

I noted what seemed to be a fair amount of timing chain stretch.
new Chain $9, new cam gear ($57), used WP drive gear/shaft $30(anyone know where I could get this new? PN10219554 - my dealer says it is discontinued and could not get/find it). +gaskets and misc stuff...

I also found the Optispark rotor pickup to be nearly worn through (must have been original), and the optispark bearing was bad as well. I need to get a new one of these as well. $250 -$500.

Since the pan will need to come down, I will be checking the rods.

If I were planning on keeping this car I'm sure I could have been convinced to go with hot cam, roller rockers, heavy duty timing set, LT4 optispark (new front cover, etc), but as it is I need to get something newer that I can seat 4 (Cobalt SS Turbo, Pontiac G8-GT, or used CTS-V) But that will leave room min the garage to work on my C2.

 

Since the WP gear mates with the cam gear I would expect to find it offered in complete timing sets. If you check different brands and sources I'll bet you can find one.

 

Piston slap. The pistons have really short skirts on them and expand at a different rate as the cylinder walls. When the engine is cold there is a lttle wiggle and it makes that noise. It's normal.

 

Did your engine noise go away after you reassembled it? I have a '92 that started making the same sound as yours on the right rear side of the engine after installing 1.6 rockers. I've gone through injectors, lifters, gaskets, valve adjustment,etc. and cannot pinpoint or get rid of the sound. It kinda sounds like a rod bearing but wasn't there immediately before the rocker replacement. Thanks

 

Seriously? This is like the thread that will not go away. Check the dates, original post Jan of last year, into Feb, then skip to mid march. Then Nov. Then all of a sudden yesterday. Wow, alot of ticking tapping huh?