Ford 256 Diesel Loud Intake...Video

[Tweeter]

Ford 5000 with 256 diesel that I rebuilt. Below is a link to a video of it running and it seems to have a loud thumping intake. Is this normal?

Ford 5000 Video

 

[Dieseltech]

Ford 5000 with 256 diesel that I rebuilt. Below is a link to a video of it running and it seems to have a loud thumping intake. Is this normal?

Ford 5000 Video

Popping noise at intake is USUALLY caused by an EXHAUST valve problem, not opening far enough due to being too loose, wear, or broken rocker arm, or severely worn cam lobe. When the exhaust charge does not fully exit, the leftover charge WILL pop BACK through the inlet next time the inlet valve opens. First time I heard it was years ago on dad's MF Perkins AD4.203 165 diesel. It started that same noise all of a sudden when one exhaust rocker arm had broken, and that exhaust valve was not opening at all. The Olds V-8 diesels would make that noise when the aluminum rocker arm bridges were worn and the hydraulic lifter had adjusted as far as it could. New bridges stopped the popping back noise on that engine.

 

[Tweeter]

Thanks. I will start with taking valve cover off and checking valve train and clearances.

 

[showcrop]

Ford 5000 with 256 diesel that I rebuilt. Below is a link to a video of it running and it seems to have a loud thumping intake. Is this normal?

Ford 5000 Video

Check to see if the secondary air filter is in place if there is provision for one

 

[Fritz Maurer]

If you just rebuilt it, may have missed an exhaust push rod not pushing on the rocker.

 

[Tweeter]

Pulled valve cover today. No. 1 cylinder exhaust rocker was way out of adjustment. Maybe I forgot to set that one after the rebuild.