Need advise- slight knock

[jkp62]

My neighbor gave me their old John Deere SRX75 with a Kawasaki FC290V engine. Was not running. The cooling air intake was quite obstructed, and the oil level was very low. Had not run for years. Compression is good, ( 175- 195 , cold ) - after new air filter and fresh fuel, started right up. Changed oil with 10w30 Valvoline MaxLife. Starts up instantly, seems to have good power, but has a noise- maybe a bit louder than a tick, but not ( to me ) a conclusive knock. I was thinking of draining and changing to 30W. I am about $80.00 into it, the idea was to fix and sell, but do not want to sell someone a problem. By the way, used it to mow my back lawn, noise did not get louder. Any ideas ? Thanks

 

[reynoldston]

If you don't want to rip someone I sure wouldn't sell a mower with a engine knock. The big word here is Kawasaki, parts are very pricy.

 

[EngineMan]

Get down and find out where the noise is coming from (what part of the engine)

 

[jkp62]

I`ve tried the screw driver ( handle ) to my ear, and I can not definitively say it is lower end. Part of the problem is, it is not an obvious knock- the engine is 20 plus years old, and I don`t know it`s "normal " sound. With power takeoff and drive engaged, the sound only momentarily changes, but still not an obvious loud knock. I am going to try straight 30.

 

[reynoldston]

There you go and if straight 30 doesn't work try something heavier like 90. Heavier oil is only temporary fix. Engineman gave you some good ideas try them and fix it right. As I recall that engine has a balance weight that gives problems also. I would say sell it like it is, as is, and don't fudge the buyer with heavy oil.

 

[jkp62]

Thanks for the advise on the 90W- took a little tie to find the right stuff, but it sure did quiet the engine down ( though it starts a bit slow)

 

[gregjo1948]

On a FH721V, I hand a slight knocking noise upon first starting and accelleration. Turn out to be the plastic fan atop the flywheel moving back& forth on the dowels. Installed a thin spacer below it and retorqued the flywheel bolt. Problem solved! Maybe your problem too. gregjo1948

 

[djdicetn]

Thanks for the advise on the 90W- took a little tie to find the right stuff, but it sure did quiet the engine down ( though it starts a bit slow)

With that engine being that old, I hope you are running non ethanol gasoline in it(try 89-91 octane). 90w is awfully thick oil to run in an air cooled engine...I'd try the SAE30 again, run a can of Seafoam in a fresh tank of non ethanol then see if that helps quieten it down.