A bit of history. My '53 chevy bel air has a '59 235 in it. I had it rebuilt by a well respected rebuild company that rebuilds early motors. you can check out my build thread here for all the info: http://www.jalopyjournal.com/forum/showthread.php?t=479046 The motor was rebuilt with stock specs short of a .060 bore and crank and cam regrind. It runs stock intake and single carb. Ive changed the oil, using the special "green oil" with zinc additive. I changed the special break in oil after the break in. I then changed the oil after the first 50 miles, 100 miles and 500 miles. Im just over 300 miles since the last oil change and have noticed a knock. Ive never driven over 50 MPH and never had it on the hi-way and have never ripped through the gears or pulled hole shots. At first I thought it was the 3 speed growling, because how could it be the motor? It was freshly rebuilt, right? I cut away my trany hump on the interior so that I could hear the trans while driving. My brother and I just drove it around and we recorded the audio during the drive. We also used a stethoscope to try and pin point where the sound was coming from. Turns out its not the trans at all. In fact it was pretty quiet during the entire trip. The growling, knocking sound was coming from the motor. The further up the bellhousing he put it, the louder it was. Heres the symptoms: At idle, it purrs. While accelerating and decelerating it purrs. However, while lightly pressing the gas pedal to maintain my speed, I get these sounds. Also, when accelerating up to 2000 RPM to shift, Ill get the same sounds. Ill also get the sounds if I stab the pedal up to about 1500 RPM while stopped and out of gear. Im hoping that some of you will have some advice as to what the sound is, and whats making it happen. Thanks! **THIS IS A STILL IMAGE. THE AUDIO WAS CAPTURED WHILE DRIVING THE CAR**
oil pressure is 15 when cold and less than that when driving around. When it was fresh from the rebuild it was around 45 cold and 30 when driving.
oil pressure kinda sucks. and its just a recording but it does sound like a rod knock.i dont think id drive it anymore. i would tear it down and lookn at everything as i tore it down. good luck. oh yeah, ive have had a engine devolepe a knock just after a rebuild. to this day i still havent figured out what the hell went wrong.
Again, kinda hard to tell from the video, but a couple spots in there definately sounds like a rod. However, be aware, on those old chebby sixes a loose flywheel can sound exactly like a rod knocking. You should check that first. Those old motors sound sweet when everything is right. Good luck
The engine rebuilders are doing right by their warranty. The car has been in their bay for a week, and at the end of last week they were going to pull it and rebuild it, break it in and install it. All covered. I hope I dont have to go through this again and can just drive the car! haha!
sorry to hear of the problems!.....didn't sound good used to short out each spark plug to find out which cyl rattled... Let us know what the verdict was and best of luck...
Definitely a bearing. Glad to see the rebuilder is standing behind his product. Congrats on the forthcoming rebuilt engine. Good Luck!