The other day I was starting the tractor and it was turning over hard. Then while cranking the engine there was this loud & distinct "pinking" noise. Almost as if someone stuck a piece of steel with a ball peen hammer. To me it sounded like maybe a valve had hit a piston. My buddy was standing there with me and we decided to crank the motor to see if it would happen again/ I know, not a great idea but I was already frustrated. So... while cranking it made the loud "pinking" noise 2 more times and then it wouldn't do it again. The pinking noise DID seem to follow a pattern as it didn't happen every stroke. It would turn over for a few seconds before the noise was heard. Feeling quite sure the engine had dropped a valve I pulled the head and see no evidence of a valve problem. The pistons look good and so do the valves. No marks that I can see.
Events that led up to this:
In recent weeks while running the tractor I noticed the motor was "stumbling" a little bit but would recovery quickly and then run ok. Also, over recent weeks I noticed that the motor was starting to crank over harder and harder and was becoming more difficult to start. I can't think of what would cause such a loud high pitched and distinct noise like that. Anyone ever experienced this issue? I'm not sure where to go from here except full teardown and rebuild :/ Thanks in advance for your time and valuable knowledge.
Lastly: I attached a pic of the injection pump. Is this the SIMS or CAV pump?
thanks!
Events that led up to this:
In recent weeks while running the tractor I noticed the motor was "stumbling" a little bit but would recovery quickly and then run ok. Also, over recent weeks I noticed that the motor was starting to crank over harder and harder and was becoming more difficult to start. I can't think of what would cause such a loud high pitched and distinct noise like that. Anyone ever experienced this issue? I'm not sure where to go from here except full teardown and rebuild :/ Thanks in advance for your time and valuable knowledge.
Lastly: I attached a pic of the injection pump. Is this the SIMS or CAV pump?
thanks!