Engine Ticking noise is driving me crazy

keel

Active Member
Aug 23, 2020
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Seattle, Wa
My 302 has been ticking very loudly for over two years now (since I've had the car), sometimes it gets better, sometimes it gets worse, but overall it hasn't changed no matter what I do to try and fix it. It is bone stock except for the exhaust. I have now replaced the entire exhaust (as well as the gaskets a few times) thinking that it was an exhaust leak, and no difference. I have replaced the stock heads with another set of stockers, no difference. I have replaced the lifters and pushrods. I have tried different oil additives, like marvel mystery oil, oil stabilizer, and liqui-moly engine flush. I replaced the oil pump and shaft. I tested the hot oil pressure at idle, and it was a healthy 25 PSI at around 650 rpm. With all these different things I have tried, it would seem that even if it didn't solve the problem the sound would at least change.

The car has also been an extremely reliable daily driver even though I drive it like I stole it these last two years and runs like it is brand new which is why I am reluctant to tear the bottom end apart.

At this point it seems to me like something bottom end related because I have exhausted all my other options. Could a worn lifter bore or worn cam bearing cause a low oil pressure condition in the lifters? I haven't seen any glitter in the oil when I change it though. If anyone else has had the same issues then I would love to hear how it was fixed because it is irritating me to no end.
 
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Be an investigator, get a piece of tubing and a hose, I like 7 /1 6" to 3 /8" and hold one end to your ear and poke the other end around stuff like valve covers and exhaust , since the gaskets have been changed at the header (right?) I would suspect the egr tube at the back of the heads.
 
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I apologize for not being clear, but it is stock from intake to oil pan, there are some exterior modifications. yes I am sure that all the components inside the engine are stock I’ve had the top end apart a few times now and the oil pan off as well. The egr system has been deleted and the holes in the back of the head have been plugged, and the car has bbk long tube headers with a catless x-pipe. I have probed the engine with a long screwdriver up to my ear and the sound seems to be coming from the passenger side top end, but beyond that it’s pretty difficult to find exactly where the sound is coming from.
 
When you say you replaced the stock heads with another set of stockers was that rockers and all? Even though the stock rockers are bolt down they still need to be shimmed. May have some lash that needs to be removed. Just throwing it out there.
 
Yes I bought a set of stock heads with the rockers and valve springs included. I was not aware that they needed to be shimmed, I will look into that. However, I will say that the noise was still present even when the engine had all of its original parts.
 
This is a direct quote from Michael Yount over on the Corral (he it very technically sound) with regards to stock rocker arm adjustment and so thought it may help:

Technically - the stock (and most bolt on pedestal rockers) are not adjustable. But there is a procedure for installing them.

Rotate the engine around clockwise until the intake valve on the #1 cylinder starts to open. Use a socket and breaker bar on the balancer nut. As the intake opens and then begins to close keep rotating until it closes - you can usually wiggle the rocker just a bit once the valve is fully closed. If you've got help turning the engine - lay your hand across the pair of intake and exhaust valves while your buddy's turning the engine. You'll feel the intake come up and close - it'll be at the same height as the exhaust rocker. At that point you are at the end of the intake stroke and both intake and exhaust valves are closed. Loosen both nuts and then hand tighten until there is no gap/lash on either the pushrod end or the valve stem end. From that point torque to 17-20 ft-lbs. and count the number of turns it takes to get there. It should reach the spec'd torque somewhere between 1/4 and 1 turn. If it takes more than 1 turn to reach the torque, you can add shims (.030", .060", .090") -- each .030" shim will reduce by about a 1/4 turn the amount it takes to reach the specified torque. If it takes less than a quarter turn to reach the torque, you need shorter pushrods. If your heads, block and rockers are unmodified, then as a practical matter - almost everyone finds that you can just torque them to 20 ft-lbs, and that will occur between the 1/4 and 1 turn spec.

Once your're done with #1, use the distributor cap as a guide - follow the firing order of the engine (on the HO's #3 is next) and rotate the engine until that intake is just closed. Following the firing order, you'll only have to rotate the engine about an 1/8th of a turn for the next set of valves.
 
Here is a much simpler way...
Adjust the intake as the exhaust starts to opem
Adjust the exhaust as the intake starts to close.
 
You mentioned a lot of stuff but no mention of if the camshaft has been checked. If a camshaft has a wiped lobe it can cause a tick even on roller camshafts.

If it's on the passenger side you can remove the valve cover and reinstall the throttle body to actually see what's happening. At idle it should squirt too much oil around.
 
Dumb question, because I'm experiencing a ticking that is driving me F(*&ing bonkers, too. It's also coming from the passenger side, near the firewall and though it's probably in the engine bay somewhere, it could, I suppose, be in the cab. Anyways, the best clue I have is that I can quickly toggle the key off/on not even allowing the RPMs to stall. The car fires right back up and the tick is gone for a minute or two. Now, I think that rules out just about everything that's mechanical. Lifter tick, exhaust leak, etc... wouldn't care about a quick off/on for a moment and would go right on ticking.

Is your tick present immediately when you start the car? Is it there after toggling the key like I do? Would love to have someone else with the same problem to help investigate it.

Anyways, if I had to guess, given that you've replaced everything on the top end and exhaust, I'd say it's something like piston-slap. If the toggle test eliminates it, then I'd guess, like mine, that is has to be something related to or affected by the electronics.