97 350 Vortec lifter ticking first 3 mins

[made2drag]

I'm not much of an engine guy and wanted to get some ideas.

Ive been driving my Tahoe and put stock exhaust on it on a Tuesday. Then the next Monday, i get in my Tahoe and i hear a horrible tick. I pop the hood and listen around and its coming from the driver valve cover. I can feel a vibration in the middle of the cover. Its loud at first, then gradually gets quieter... after about 3 mins, i cant hear it at all. Its definitely not an exhaust leak. Ive been under the truck and the muffler guy checked for leaks.

When i crank up anytime after the first start up, its fine. When it sits overnight, the first crank up it ticks. Ive had it since October and it just started doing it. Ive cranked up when its 60* out and it ticks.

I did an oil change (after driving) and i cranked up and its quiet (new oil which is cold and thick still). Next morning it ticked again. I'm using the correct Wix 51036 oil filter and I'm using Castral GTX 5w-30 oil.

My oil pressure on start up goes quickly to 40 psi and it stops ticking at 38ish. Ive tried Lucas and my pressure is 50 psi on start up and 45ish after the tick goes away. No drops in pressure until i drive it awhile which is normal.

Ive seen a lot of posts all over the internet but i have no clue what to believe.

Any ideas are welcome. I'm hoping people can tell me what it is and maybe a fix. I'm not one to start yanking covers and turning on rocker nuts or taking things apart unless its needed.

[made2drag]

My oil level stays at the normal full line. No smell on stick, not green or anything. I do have a slight coolant leak because i keep having to pour a little in my overflow tank once a week. Exhaust pipe isn't blowing any smoke but i have noticed a wet spot on concrete under exhaust pipe on start up and after a couple mins of idling.

Engine sounds strong, quiet and no weird sounds once the tick goes away.

All stock, no teenager tricks under the hood.

[made2drag]

I'm only guessing it might be lifters. I guess i shouldn't have named the thread like i have it narrowed down. LOL

[Tom]

Sounds like lifter, rocker or piston in that order of likely.
Once the oil warms up the lifter stops sticking and gets quiet. I'd pull the valve cover and put some oil deflectors on and run it to see whats going on with the rockers first.

[Dead Parrot]

Double check your exhaust right where the water spot is unless it is the normal end of tailpipe spot. Water could be telling you where the leak is. Not unheard of for an exhaust to leak cold and mostly seal up hot. Could be why your exhaust guy didn't find anything.

Since the exhaust was changed just before the tick started, I suspect the exhaust first.

If you still have the old filter, check for metal bits that might indicate a cam going bad.

[truckster]

Originally Posted by Dead Parrot

Double check your exhaust right where the water spot is unless it is the normal end of tailpipe spot. Water could be telling you where the leak is. Not unheard of for an exhaust to leak cold and mostly seal up hot. Could be why your exhaust guy didn't find anything.

Since the exhaust was changed just before the tick started, I suspect the exhaust first.

If you still have the old filter, check for metal bits that might indicate a cam going bad.

I would also suspect exhaust. A cam going bad in a Vortec engine is extremely unlikely.

If it is a lifter, running a quart of Marvel Mystery Oil through the engine prior to the next oil change could clean it up and make it work again.

[burnin oil]

I second the mystery oil after pulling the valve cover for a visual. Hydraulic lifters have the tightest tolerances of any engine part. I suspect one is worn around the plunger and leaks until thermal expansion closes the gap. What all these means is the lifter bleeds down and has some valve train slop and once warm it tightens up and gives full lift. If you find a loose rocker dont give it more than a 1/4 turn if the motor isnt up to temp. Once its warm it could keep the valve off its seat depending on how much preload the factory gave it.

I ran a set of 305 vortec heads years ago that had some noise. I pulled the valve cover and the pushrod had broke through the rocker arm. With the valve train geometry all messed up it beat up the retainer, locks, and grooves in the valve that the keeper grabs. I was minutes away from a valve drop. She still had good oil pressure and the noise really wasn't that loud. For the solid lifter guys it sounded just like when you back off the adjuster and get that slight tap when you go to reset the lash.

[made2drag]

Originally Posted by Tom

Sounds like lifter, rocker or piston in that order of likely.
Once the oil warms up the lifter stops sticking and gets quiet. I'd pull the valve cover and put some oil deflectors on and run it to see whats going on with the rockers first.

Great idea, thanks! I also think it might be the lifters sticking. Lots of sludge in the motor, for sure.

[made2drag]

Originally Posted by Dead Parrot

Double check your exhaust right where the water spot is unless it is the normal end of tailpipe spot. Water could be telling you where the leak is. Not unheard of for an exhaust to leak cold and mostly seal up hot. Could be why your exhaust guy didn't find anything.

Since the exhaust was changed just before the tick started, I suspect the exhaust first.

If you still have the old filter, check for metal bits that might indicate a cam going bad.

Definitely ticking under the valve cover. Its vibrating the cover its so violent.

[made2drag]

Originally Posted by truckster

I would also suspect exhaust. A cam going bad in a Vortec engine is extremely unlikely.

If it is a lifter, running a quart of Marvel Mystery Oil through the engine prior to the next oil change could clean it up and make it work again.

I have heard of Seafoam, Marvel Mystery Oil and also people using ATF to loosen sludge and grime. So you would use MMO?

[made2drag]

Originally Posted by burnin oil

I second the mystery oil after pulling the valve cover for a visual. Hydraulic lifters have the tightest tolerances of any engine part. I suspect one is worn around the plunger and leaks until thermal expansion closes the gap. What all these means is the lifter bleeds down and has some valve train slop and once warm it tightens up and gives full lift. If you find a loose rocker dont give it more than a 1/4 turn if the motor isnt up to temp. Once its warm it could keep the valve off its seat depending on how much preload the factory gave it.

I ran a set of 305 vortec heads years ago that had some noise. I pulled the valve cover and the pushrod had broke through the rocker arm. With the valve train geometry all messed up it beat up the retainer, locks, and grooves in the valve that the keeper grabs. I was minutes away from a valve drop. She still had good oil pressure and the noise really wasn't that loud. For the solid lifter guys it sounded just like when you back off the adjuster and get that slight tap when you go to reset the lash.

GREAT advice! I'm going to check into that! Thanks!

[made2drag]

Guys, thanks so much for taking the time to read my thread and helping me. The thing i didn't want to say in the beginning is that i found lots of sludge on my dipstick, oil pan drain plug and i cut my oil filter open and it was covered thick in sludge. Like super gummed up....not even sure how oil was getting through it. LOL I'm wondering if the lifters are sticking due to sludge and just takes the heat to loosen the sludge and let them move? Like i said, I'm no engine guy. I don't know if sludge can stick the lifters or not? I do need to take care of the sludge, for sure. I kept hearing a lot of piston slap theories on other forums and people saying piston slap is not harmfull but also piston slap and lifters sticking can sound the same.

[made2drag]

Originally Posted by Dead Parrot

Double check your exhaust right where the water spot is unless it is the normal end of tailpipe spot. Water could be telling you where the leak is. Not unheard of for an exhaust to leak cold and mostly seal up hot. Could be why your exhaust guy didn't find anything.

Since the exhaust was changed just before the tick started, I suspect the exhaust first.

If you still have the old filter, check for metal bits that might indicate a cam going bad.

No metal bits, just black lotion consistency sludge inside the filter.

[truckster]

Marvel Mystery Oil is my go-to for dealing with sludge like that.

[made2drag]

Originally Posted by truckster

Marvel Mystery Oil is my go-to for dealing with sludge like that.

So how much do i put in and how long do i run the engine before doing an oil change? Do you just idle in the driveway or do you put some in and drive it awhile?

[burnin oil]

They used to sell a product called rislone just for this purpose. Pour into the oil and run 5 minutes then drain. When I was a kid my dad put it in his truck and life happened. He left it in for around 500 miles and every seal leaked after that.

On a 350 I was rebuilding I put about a quart of diesel in the crank case and fired it up. Ran the motor until pressure dropped. About 45 seconds. I swear the filter weighed 20lbs and was clogged up. Inside was pretty clean too. Many things will work but that doesn't mean I would try it on an engine that I wasn't going to tear down. Any detergent risks the chance of a piece of crap breaking free and clogging a return or the filter. Just saying.

Years ago I tore a core motor down that had so much sludge that you couldn't see the valve train. It was just a brick of sludge. Amazingly there was not alot of damage other than oil starvation. I dont know how the oil ever drained out of the head.

If your motor is that sludge I would pull the valve covers and clean as much crap out as possible. Reinstall the covers and run the motor while watching the pressure gauge. After that shut down and change oil and filter. Run it for 15 minutes and if all is good drive it for a couple days then change the oil and reassess. Cheapo oil and filters work great for this.

[burnin oil]

Originally Posted by made2drag

So how much do i put in and how long do i run the engine before doing an oil change? Do you just idle in the driveway or do you put some in and drive it awhile?

Just add it and drive. I am sure people will say to drain some oil first but I have just dumped it in. I cant remember the amount spaced by MMO but 1/2 quart overfill wont hurt. If you are really worried install a new filter, dump it in, then go until your next oil change.

[AcampoDave]

For what its worth, I have two 283 small blocks. One is fresh and one is high mileagr. Both will tap a lifter sometimes on start up. I never worry because after I drive it gently for a half mile or so it goes away. Doesnt do it every time, usually a cold start problem but now again even when warmed up. The high mileage engine has been doing it for 25 years and the other since it was rebuilt. I've always chalked it up as a bleed down problem and thought it was a "283 thing"

[made2drag]

Originally Posted by burnin oil

They used to sell a product called rislone just for this purpose. Pour into the oil and run 5 minutes then drain. When I was a kid my dad put it in his truck and life happened. He left it in for around 500 miles and every seal leaked after that.

On a 350 I was rebuilding I put about a quart of diesel in the crank case and fired it up. Ran the motor until pressure dropped. About 45 seconds. I swear the filter weighed 20lbs and was clogged up. Inside was pretty clean too. Many things will work but that doesn't mean I would try it on an engine that I wasn't going to tear down. Any detergent risks the chance of a piece of crap breaking free and clogging a return or the filter. Just saying.

Years ago I tore a core motor down that had so much sludge that you couldn't see the valve train. It was just a brick of sludge. Amazingly there was not alot of damage other than oil starvation. I dont know how the oil ever drained out of the head.

If your motor is that sludge I would pull the valve covers and clean as much crap out as possible. Reinstall the covers and run the motor while watching the pressure gauge. After that shut down and change oil and filter. Run it for 15 minutes and if all is good drive it for a couple days then change the oil and reassess. Cheapo oil and filters work great for this.

Great advice again, thanks! I do have an update. Last night I pulled the 4 cover bolts out, moved stuff out of the way, tried pulling cover off...the front lip of the cover wouldnt clear the A/C bracket to slid back and up. I cut a slice off of the bottom of the bracket and tapped a dent in the cover trying to make some clearance. Still couldnt get it out...only needed like a 1/2 inch more clearance...loosened the bracket bolts and couldn't get the a/c bracket to move forward... so after an hour of trying, I gave up getting the cover completely off. I was able to move it to the side to inspect stuff tho. What I found was black sludge on everything and globs of Lucas (yellow globs). I looked and felt around in there and jiggled the rockers one by one and looked at all the pushrods and nuts and oil holes and everything felt good and looked good. I took a rag and carefully wiped the sludge off the tops of everything. I didn't feel I did anything at all but put the cover back on. Cranked up for the first time in a couple days and WOW it made the ticking sound but only half as loud and after about 10 seconds it went away! (it was doing it for 3 mins before) I turned it off after 30 seconds and let it sit a min or 2 and cranked again and it only ticked for 5 seconds. So I backed it out of the garage and let it idle to temp. It was 50 psi cold and 40 psi warm. I don't know if it was a coincidence or something I did. I didn't drive it today, or crank it, but I'm thinking I may put 1/4 quart of Marvel in tonight before crank up and let it warm up and drive it. I'm hoping the Marvel cleans it out. I plan on another oil change in a couple 100 miles and may run a 1/2 quart with every oil change in the future and cut open filters to see the progress. Once all clean, I may go straight oil again.

[made2drag]

Originally Posted by AcampoDave

For what its worth, I have two 283 small blocks. One is fresh and one is high mileagr. Both will tap a lifter sometimes on start up. I never worry because after I drive it gently for a half mile or so it goes away. Doesnt do it every time, usually a cold start problem but now again even when warmed up. The high mileage engine has been doing it for 25 years and the other since it was rebuilt. I've always chalked it up as a bleed down problem and thought it was a "283 thing"

Cool, thanks! Mine had 210,000 miles back in 2010 according to Carfax. Cluster has been changed so no records since...im thinking it's got 300-400k on it. When I got it, the seller told me it sat for 10 years... I also noticed he had a Fram oil filter on it. I have heard horror stories about those.

[68Timber]

Here's some pics made2drag sent me.

[68Timber]

He has a short video too he really needs to upload.

[made2drag]

Thanks John! (68Timber)

I'll try to update my progress of clearing the sludge using this thread... in hopes it helps someone else out down the road.

Cut open filters pics will be coming soon after each phase......

[68Timber]

missed one... you're welcome!

[made2drag]

I was very tempted to put some MMO in a spray bottle and spray all over the head, but didn't.