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1970 Chevelle 454 - ticking sound

I recently bought a 70 Chevelle 454 from a guy that let the car sit for 14 years. (A shame, I know.) Right after he bought the car, he put a new motor in it and only put ut 50 miles on. The only problem I’ve had is that when I start the I hear a ticking sounds coming from the front left side of the header/exhaust manifold. To troubleshoot, I’ve tightened the tie rods and checked to make sure the seals were covered on the value covers. The ticking sound does NOT exist when the water temp is below 170 OR at higher RPMs.

I’m guessing the problem is that header gasket has sat for too long without the car being used, but before I invest that much time replacing it I wanted to see if anyone else had some suggestions.

Thanks!

Headers will “tick” as they heat up and cool down. After a few miles of driving at highway speed shut off the engine and listen. You may hear the sound as it cools.

With no clue about your level of understanding of mechanical repair, it’s very hard to help you. What I can say is take a piece of heater hose or garden hose a few feet long, put one end at your ear and use the other end to sweep around the engine compartment while the ticking you describe is happening. This should lead you to the place where it is the loudest, and that may help determine the problem.

I think I would be looking more for a stuck/sticky lifter than an exhaust manifold, especially since you said the vehicle had sat idle for so many years; and yes it is a crime that such a vehicle was left this way. Yes, the metal will expand and contract as the temperature changes, but in my experience (albeit many years ago) exhaust manifold gaskets leaks tend to tick all the time and do not appear with temp changes.

Even though you said you tightened the “tie rods” I’m guessing you actually meant you adjusted the push rods, but a stuck or sticky lifter may not be resolved by making such an adjustment.

I could just be valve noise, I am assuming you checked and replaced the old oil. If it is just valve noise, try Marvel mystery oil, little in your oil and a little in your gas. I don’t know exactly what it does to stop the noise, but it does work.

Could be valve noise, could be a small exhaust leak, could be normal header noise.

There’s a reason OEMs use cast iron exhaust manifolds instead of tube headers: cast iron manifolds are far quieter than tube headers. That may be the noise you’re hearing. A small exhaust leak at the header flange may make a “ticking” noise, and a misadjusted valve will make a tick. A dozen other things can make ticking noises, too.

A '70 454 with only 50 miles on it probably isn’t the right place to experiment with solving noises. You’re going to want to have somebody with more experience take a look and maybe lead you with maintaining this car.