Ok, this has been driving me nuts ! I have a 1960 Biscayne with a 355, dart heads, mild hydraulic roller cam, headers and a Muncie 4 speed. Both the engine and transmission are rebuilt with less than 6000 miles on them. A new clutch, flywheel, T.O bearing. When I start the car cold and drive it, I get a ticking noise above 1500 rpm. It goes away when the car is warm. I've pulled the valve covers, checked all the rocker adjustments, locks, etc. it has tall valve covers. The tick actually sounds low, like under my feet or from the bell housing area. I've crawled under the car, banged around looking for rattles, removed the headers and looked for vibrations. But when the car has been driven for a bit and everything is warmed up or hot, I don't get the noise. I've thought maybe a loose clutch bolt or flywheel bolt, but why does the noise go away when warm ? Any advice would be great !
Sound that goes away when warm is often piston slap and /or a loose wrist pin , could be pre ignition , header leak , drive it . If it's catastrophic ,it'll show you sooner or later . I've owned an 84 GMC 454 1ton crew dually that's had a cold engine rattle for the last 125k miles ( 39 years) still runs great , doesn't use oil , we think it's a loose piston .u
It's not an exhaust leak, it's more of a mechanical tick. I've put new header gaskets in when I took the headers off. It's a good observation though !
Possible I guess, but not many miles on the engine. I do drive it and yeah that's my thought, if it's anything serious it will rear it's ugly head at some point.
My car with a similar drive train had a TO bearing that was noisy for the first 1000 miles. Get a helper to track it down, use a hose or wooden dowel to "listen" with.
On a rod run and developed a ticking noise on a SBC, sounded just like a rocker arm, 100 miles later the fuel pump died.
Do you know if you've got cast or forged pistons? Forged pistons tend to be installed with a couple thousandths more cold skirt clearance than cast pistons. As a result they can also be a bit noisy until the engine warms up and the pistons expand to take up the extra clearance. You might also start the engine cold and bring the idle up until you hear the ticking. Then remove one plug wire at a time and see if the ticking stops. This might help to narrow down your search for the noise to one specific cylinder. Then you can concentrate your efforts on things that are specific to that one cylinder, like a piston or wrist pin or bearing noise. If the noise is present even with each plug wire individually unplugged then you can concentrate more on things mentioned above like the fuel pump or its push rod. Or something in the clutch or an exhaust leak which can make a "ticking" noise in the right situation.
Fuel pump. Had one years ago and the little return spring was broke. Ran fine until I sold it and was still going last week with the tick.
It's a vortec block with factory style lifters. I don't get any engine noise if I bring the rpm's up, only when I drive it "cold".
It has hypereutectic pistons. Electric fuel pump, I don't get any engine or lifter/rocker noise when I bring the rpm's up in neutral. It's only when I drive it cold and it's above 1500 to 2500 rpms. I don't believe it's an exhaust leak. I replaced the header gaskets with copper ones and I have ball flanges at the collectors. The headers on this car curve out towards the fenders because it's an X frame car and the noise seems to be more center. If I could put a stethoscope under it and drive it or ride under the hood to help locate the noise that would be great, but that's pretty impossible and dangerous.
From a cold start to warm... probably 5 to 10 miles. Car runs at 180 even on the hottest days. It's strange, I can kinda "feel" it and that's what made me look for something vibrating. It really does sound like loose rockers but I can kinda feel it down by my feet in the toeboard-tunnel area. I think I'm going to remove the clutch inspection cover and take a look up in there and/or drive it without the cover on just to see if possibly that might be part of the culprit. That reminds me of a joke... Do you know what an Australian kiss is ?? ....... It's like a French kiss but from down under
Is the ticking noise intermittent, constant interval, or does the interval change with engine speed or vehicle speed or by changing gears at a constant speed? Does the ticking diminish as the engine temperature rises or just quit at a certain temperature. The fact that the ticking doesn't start until the vehicle is moving would lead me towards the drivetrain, esp. since you can "feel" it in the toeboard. Have you tried putting the vehicle on jack stands and duplicating the ticking? (Might not work because of no load on engine/drivetrain. A light application of the parking brake may simulate that.)
The tick seems to increase with rpm, like loose rocker arms would. I can't say that it quits at any certain temp. I live just outside a very small town so when I start the car and drive it I have to leave the driveway and head out a short distance to a stop sign to get on a main road. The car is a 4 speed so I really notice the tick.. maybe even call it a clatter.... when I'm running it up through the gears. If I drive to a town about 6 miles away, the noise is pretty much gone by the time I get there. At hwy speed, 60mph I don't really notice it. Now that I think about that..., I'm running about 2500-2700 rpm on the hwy and don't notice it. It has a 3:70 gear ratio. Humm, I'm gonna have to drive it down the hwy asap just to verify that I don't hear it. I will try and get some audio/video to post. Stay tuned !
Had the same exact ticking sound that I could not determine where it was coming from. Finally put it on a lift with the engine running and immediately found the problem. When I had installed the flywheel/dust cover plate to the bellhousing I had failed to properly secure one side of the plate up to the bellhousing and it was vibrating. If I hadn’t put it on a lift with the engine running I would have never found it!
While its ticking, try removing the plug wires one at a time and see if it stops. Then you may know which cylinder is the problem. Piston slap can be difficult to pinpoint, mostly because people are hoping thats not the problem. Sometimes a different oil can help.
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