Knocking type noise, like a piston sound -- increases with rpm.
Cannot isolate where it's coming from. Thought it might be air pump, but sounds like it's farther back.

I've posted the video on various sites to try and get some ideas.

Any help is appreciated.
Fresh rebuild and the tranny has been off the engine recently.

Thanks for any ideas.

 

go get yourself a stethoscope from kragens and start probing around, they can be your best friend when trying to isolate noises.

 

I have the Harbor Freight steth, but it hasn't help me isolate the location.

thanks

 

who rebuild this engine has it made the noise from first start up? i hope it wasnt anything under the front cover

 

The builder has done great work all along. He will stand behind it if it turns out to be internal. Really trying to figure out what it is before having to pull the engine again.

Drove the car 200+ miles yesterday, oil pressure steady the whole way, vacuum at highway speeds constant at -16. Temps never above 160F. Noise still noticeable at idle. Running premix now as an extra precaution.

thanks

 

Hard to tell but could be loose clutch bolt. Remove the dust cover and turn the engine. Look for shiny metal

 

Thanks -- I would LOVE it to be clutch related.

 

Car also has a "vibration" issue under any type of pull. Vibration sounds through the cabin plastics and maybe the rear struts. Hoping this is another pointer to the clutch/throwout bearing area. Also, sound may not be there at initial startup, at least not every time. But, it is there by the time the drive is over and car is ready to be shut off.