Name this tick!

[AdamIsAdam]

Who can help me name this tick? This morning after driving for a while I started to notice what almost sounded like a header gasket leak or maybe a rocker tick. I recorded it to share. I'd love to hear your thoughts.

It was pretty warm today, but not crazy hot. I was driving it spirited but nothing crazy. I went home and pulled the valve covers and checked for obvious signs of the rockers being out of adjustment, but everything looked ok. I was going to reset the lash adjustment but the few poly locks I tried were so tight I couldn't loosen them, so I left them alone. I could just barely spin each pushrod but nothing seemed overly loose.

The sound is more prevalent on the drivers side valve cover area.

Here's some details:

Car is new to me this winter. Engine has 1,800 miles on it. It's a 347 stroker with TEA Twisted Wedge 185 CNC heads with FordStrokers PAC HYD roller spring package (per the receipt).

Oil pressure is good (60 psi and 2,000) and oil is fresh this season 10x-30. The car runs fine.

I recorded the sound only but needed to make a video just to get it up to YouTube so you can ignore the slideshow lol, close your eyes and listen.

NOTE: There are two audio clips. The second clip starts at 25 secs and I raise the RPM a bit which makes the sound go away, so not likely a header gasket leak.

https://youtu.be/Z6NQ1R5wBJo

[HighPlainsDrifter]

Sounds like an exhaust valve. Probably a bad lifter not holding oil.
good luck,
Perry

[ERA 626]

He beat me to it... lifter not pumping up.

[AdamIsAdam]

Hmm. And it goes just like that, suddenly?

I'll go pull the valve cover again. is this the way to diagnose it? When I touched them all earlier, nothing was super loose, but I was not pushing down on the lifter, I was just checking to see if the pushrods were loose and spinning easily by hand, which they were not.

https://www.youtube.com/watch?v=Tl9oDaMLCME

[patrickt]

If an exhaust valve is not opening properly, then the primary pipe that is associated with that valve will not be in the same temperature range as the other exhaust valves. Start the car up when it's cold, and hopefully the tick is still there, and use an IR gun to monitor the temperatures of the 8 primary pipes and see if one is really out of whack from the others.

[AdamIsAdam]

Thanks, Patrick. So I assume I'm looking for one header tube that is cooler than the rest, right?

Also, what typically happens? Is the lifter just not holding pressure or do they come apart sending springs and lifter parts into the engine? (I realize when I pull the intake, I'll know for sure, but I was just wondering what you typically see.)

Lastly, will it hurt the car to run like this? (not forever, but just to my friend's garage)

[patrickt]

Who knows. Five minutes more of diagnosing in your driveway isn't going to cause any more damage than what's already there. But remember, I have solid lifters, so they're all collapsed. Watching the valve train with the covers off would also tell you if a valve wasn't opening, but that usually makes a mess.

[AdamIsAdam]

I just pulled the valve cover again and all lifters seem to have the same resistance. Which is to say they're all quite snug. I'll do the heat test tomorrow so as not to annoy the neighbors .

[patrickt]

Usually when you lose one cylinder's worth of power you can feel it. But, the car's new to you so you might have missed it. Or, it's something else and you were running on all eight cylinders all along.

[AdamIsAdam]

It was running well today. I was getting on it a fair amount too, nothing crazy like I said, but it was running well. I started it up earlier after it sat for a few hours to see if the oil temp made any difference since this is the warmest day since I bought it, and the tick was right back again.

I don't want to get ahead of myself here, but if not a lifter, what's the next thing to look for (assuming the heat test shows all cylinders are equal temp)? Spun rod bearing? Yuk!

Remember, the noise goes away when I increase RPM's (listen to the video at about 25 seconds).

[patrickt]

If the car runs well, the pipes heat up evenly, and you even watch the valve train with the covers off and every valve goes up and down cleanly, then I would try and locate the tick using a mechanic's stethoscope. An engine tick coming out of a Surface is a little tricky to identify. The fact that your engine runs well is a good sign. A stethoscope will help you spot the location of the noise, if it's mechanical (it could even be something like a mechanical fuel pump misbehaving).

[AdamIsAdam]

I did put a long screwdriver to my ear today all around the valve cover, the intake manifold and the header tubes and honestly, it sounded better inside the engine than outside. It also sounded even everywhere I poked at it.

I'm not crazy in thinking a header gasket leak would sound the same as RPM's go up, right?

Mechanical fuel pump, hmm. I'll take a listen in that area. Wouldn't that be a nice easy fix!

[patrickt]

Stop off at the auto parts store and pick up a stethoscope. It's way better than a stick or screwdriver.

[AdamIsAdam]

ok, I'm back from the big Cars & Coffee at the beach (took my other car) and i'm ready to get back into the Cobra. I picked up a stethoscope. Before I get started and heat up the car, I figured I'd try to take videos showing the header gaskets. It does sound like a header gasket leak except I wouldn't expect that noise to go away with more RPM, but maybe.

The first video is from above, front to back of the engine. Cylinder 5 seems to have a little oil above the header flange, probably from removing the valve cover. MAYBE there's some exhaust soot on the rear side of #8. I'll check the header bolts while it's cold as well.

Video 2 is from underneath and hard to focus, but it looks clean to me.

What's the torque on header bolts in aluminum heads, anyway? I'll check them even though they have lock washers.

Oh, and I'll connect the remove starter switch and crank it with the valve cover off to watch the rockers move before putting that back together.

Any other thoughts on what to do on a cold engine?


From above:
https://youtu.be/3mWaIb3-zoA

View from below (hard to focus, sorry):
https://youtu.be/DSfF2job2JE

[patrickt]

If you suspect a leak around the gasket you can spray a little soapy water water (dish washing liquid and water mix) around the area and look for a bubble formation.

[patrickt]

If you're young enough to still have kids that use Mr. Bubble in the tub, that stuff works exceptionally well, and gives your engine a fresh clean scent too.

[AdamIsAdam]

LOL my kids are beyond Mr. bubble. Okay so I found a flaw with locking washers. Almost Every single bolt is slightly loose because it's in between the next flatsided part of the head. In other words I can't get another rotation out of the bolt to make it a little tighter. I will snug them all up against the lockwasher and give it a try. Standby Mr. bubbles

[jhv48]

My bet is an exhaust leak. If the lifter isn’t pumping up, the sound would not Disappear when revved and then return at idle.
Tighten your header bolts. Although, if the gasket is blown, then tightening won’t make a difference.
Use your stethoscope on the exhaust manifold, one cylinder at a time. Bet you’ll find it.
Leaking exhaust manifolds are common. Sound can disappear once warmed up. Easy to replace.

[6TNCRZY]

If you are checking for a leaking lifter make sure you check each one when the valve is fully closed. Sound is more like an exhaust leak to me, The sound seems a little random and varying in intensity, a mechanical issue is usually very consistent.

[AdamIsAdam]

I tightened all header bolts up against the lock washers. With valve cover off, I cranked the engine and watched the rockers, everything looked ok.

I sprayed soapy water, then I fired it up. The water was gone in seconds. It's ticking away. My stethoscope doesn't tell much. The valves are quiet, fuel pump, water pump, distributor. All quiet. The sound seems to be coming from drivers side front, down low I think.

I took temp readings of exhaust and every cylinder was about the same.

It's possible it still has a header gasket leak, especially if it's from the bottom since I can't get my stethoscope under there. Otherwise, what can it be? Spun bearing? Yuk

Do header gasket leaks go away with increased RPM like mine does? It's been a long time since my last one.