[unkajed]

My tractor now has 25 hours on it. Since day one, I have heard a knock. Perhaps I am not use to a diesel engine. I don't know.

Basically:
I turn on the ignition switch to glow plug. The glow plugs stay on for about 8 seconds or so. Glow plug light goes out.

I start the engine: Oil lamp/light goes out and I adjust engine speed to approx 1500 rpms and I let it warm up.

When I start it I hear knock, knock, knock. I hear this sound regardless of load, no load, rpm, transmission engaged or transmission not engaged.

The tractor is not smoking whatsoever.

I can make the knock go away by quickly lowering the rpm's via the throttle lever.

Let's say I am idling the engine around 1500 rpms. I adjust the throttle level all the way down to 1000 rpms which is the minimum rpm and the sound goes away until I guess it starts the injectors again to supply fuel to maintain the minimum rpm. Then the sound starts again.

Perhaps I am hearing Ignition Knocking.

Even though I am at 25 hours, I am considering changing the oil in case the tractor set on the lot for a while and perhaps the filter failed, is failing or something. Maybe the factory uses cheap engine oil for initial break in.

I know one thing. When I do change the oil, I am going to run the old oil through a pair of women's hose just to see if I have any metal particles.

If it is ignition knock, what can I do to quiet it down?? Higher centane rating?

It has not failed but it defintley sounds different than a gasoline engine.

I called my dealer and basically he said don't worry about it unless it fails.

Any suggestions or comments???