[paulnettiewv]

1958 641 with power steering and a Sherman trans has been running great for many years after rebuild 2003 but today after setting two months from a 20 acre bush hog day the engine had a loud knock when it started up then went quiet then started knocking again so I shut it off. Oil has been changed a year ago and is full. No leaks in Radiator. Hydraulics are very slow at start - takes 25 minutes to get it to lift. Now what do I do about the engine knock?:dunno:

 

[Kirk-NJ]

What does the oil pressure gauge read when knocking and not knocking when quiet? Take a short piece of hose,stick in your ear and put the other end on different parts of the engine to try to locate where the noise is coming from.You might have to drop the pan for a look see.
Did it knock when you had the 3pt lift engaged? You can bleed the pump with the hex head allen key on the pump. Might help the lift but you might have to open up the side cover to see what's going on.

Kirk

 

[JohnW]

You can also try removing one spark plug wire at a time to see if it changes on a particular cylinder. Could the noise be from behind the engine? Does it change if you push the clutch in?

What does the oil in the hydraulics look like? When was it last changed?

 

[paulnettiewv]

Thank-you Oil pressure is 18psi after about 5 sec. Knock is load until oil pressure gets to 18 then quiet but after a couple of minutes it starts again very low and toward the front of engine. Found a mechanic who works on Gravely and tractors and says he can just drop the oil pan to see. Will keep you all posted. Hope for the best.