LT1 ticking
 

My car has 41200 miles, all stock internals. Stock exhaust manifolds. Mobil1 5w30.

Engine ticking not immediately heard during cold start. Noise starts 2 minutes into the warmup, lasts another 10 minutes before quieting down.

Took to 2 shops (one was a dealer). Both say they need to take it apart and find out what is causing the tick. The non-dealer shop tells me I'm losing oil pressure (which shows 50-60 cold start, as low as 15-20 idle when warm but 40-45 when rpms are above 1500-2000....only time it actually loses pressure is when accelerating WOT). This shop says it should always be above 40 no matter what...

Trying to find a few shops in the Central Jersey area that can do a proper diagnosis and pinpoint what is really wrong. Or do ingo with a different oil, or go thicker than 5w30, or run an oil additive? Thanks!

Sounds like a lifter sticking. Maybe do an engine flush or try some additives to free it up. I would try this first before taking motor apart.

Losing oil pressure at WOT is bad but don't think its directly related. A mechanic's stethoscope sounds like a wise investment at this point.

Actually the loss at WOT occurs around 4500 rpm, maybe 30 psi briefly then climbs back up as it goes past 5000 to redline.

Hook up a manual oil pressure gauge and verify your gauge isn't the issue

Search the web a bit, could be windage or could be worse. Either way, losing oil pressure while increasing rpm is not good. Not a bad idea to check with a manual gauge to verify though.

What about using a different brand of 5w30 oil? I did a google search and have seen quite a few stating that 5w30 Mobil 1 in particular is one of the "thinner" 30w oils (some say it's actually too thin for LT1 cast iron blocks).

Should I step up to Mobil 1 0w40?

If that's the course of action you want to experiment with, give it a shot and let us know how it works out.

I think used to run Mobil 1 15W40 or 20W50 in the summer months on my old 93 Pace Car when it had the supercharger on it. I think I ran 10W30 or 10W40 in the winter. I know 5W30 made a lot more noise so I went up to a heavier weight oil. And you could always tell when it was time to change the oil as the ticking or piston slap at start up would get louder over time.

You can try to diagnose the issue or you can bandaid it.

Do it right or do it twice.

Keep us posted :popcorn:

I checked the oil level, it's full. Only thing I can try is switching back to my usual K&N HP2002 oil filter (the dealer used the acdelco PF454 last time it was in the shop getting some oil leaks fixed).

If changing the filter does not help I'm afraid I'm gonna have to let the shop take the engine apart.....hoping it's something minor, a lifter or rocker being the worst they find.

Ok...car is in the shop. They pulled the valve cover off and told me they readjusted the rocker arms and got it quieter but said I should have the lifters changed.

Thoughts?

Sounds reasonable

Factory rockers should be incredibly quiet and odd to have loosened enough to make noise at 41k miles. Out of curiosity sake, see if the shop will tell you how the adjusted the rockers. Then based on the bill, you can see if they just cranked em till the noise went away or did it right.

Thankfully, lifters on a SBC are easy to do, so if it comes to that, not terrible.

Unfortunately the noise is still there. And the shop is telling me I need a new engine (they dont want to touch the lifters, thinking they may find other things wrong in the process, etc).

Gonna look for another shop for another opinion....

One more thing they showed me - slight sludge buildup on the pushrod (it was on the ball end of it).....

What does that mean? I have done regular oil changes and used Mobil 1 5w30 since it had 6000 miles, and my oil change intervals were always between 1000-2000 miles, at least once a year (car hasn't been driven much)...

I'm not sure if you have an auto or manual trans but I remember years ago I had a similar ticking noise with my car that drove me crazy. The noise would come and go as the engine temp would change. Ended up being a hair line crack between the flexplate bolt holes. The flexplates are known to crack there. It was so small to see but if I tapped the flexplate with a hammer you could hear the difference in sound near the crack. :nod:

I have an auto. And yes, my tick seems to come and go depending on engine temp (how long it's been run). When I picked up the car, tick tick tick tick tick.....by the time u got home......much quieter. Parked the car. washed it, started it up, tick was almost non-existent!

Car still runs/drives fine other than the ticking. What's worrying me is the engine sludge they found on the pushrod...also they insist it's coming from inside the engine.

Sludge can be caused by a number of reasons. Have you checked the pcv valve? I noticed you also have a 160 thermostat, cold winter air and short trips can lead to sludge build up. Oil temps need to be hot to remove water and vapors from oil.

I recently changed the PCV valve, no gunk found on it. I also don't see gunk/sludge inside the valve cover (based on what I see when I open the oil cap).

Pic of underneath oil cap. Taken moments ago....

Ok...I start it up this morning on my way to another shop for another opinion.

Once again the engine was not ticking at all (right after firing it up). I then proceed to the shop, ticking started just as I pulled in. They think lifter, as I was thinking all along but they need to pull a valve cover and see. Worst case, they said I'll need the lifters replaced (I asked if they think I need a new engine, they laughed saying definitely no, not for this type of noise)..

The tick was faint, eventually goes away after driving a while (to the point where I only hear the "typical" LT1 tick I've heard since new).

I'm almost ready to leave it alone since it does go away once the engine has been running for a while...or is this something I need to take care of asap?

This morning I start the car, 5 minutes after idling I start driving, and hear a tick around 3000 rpm which I never heard before!

1-2 minutes later I was not able to reproduce the noise.

I dont know what to do!

https://i.redd.it/ccle328l1iq21.jpg

You've been given advice and have done nothing with it.

Actually, I've been to 3 different shops for this issue, nobody has a solution.

Shop 1 (dealer) - tried readjusting rocker arms, thought they got it better, ticking returned. Now they want to sell me a new engine.

Shop 2 - tells me they need to tear it down and find out what is going on, says I'm losing oil pressure (but my gauge still shows 50 on cold start, 40 cruising warm-hot, 20 idle hot).

Shop 3 - yeah its ticking but I would just leave it, not serious enough to tear engine apart...maybe step up to a thicker oil like 10w30