etpm
Veteran Member
- Joined
- Jun 30, 2021
- Messages
- 2,053
- Location
- Whidbey Island, WA
- Tractor
- Yanmar YM2310, Honda H5013, Case 580 CK, Ford 9N
A month or so ago I bought my first Yanmar. A YM2310. It was also my first diesel. To my ears it sounds like a typical diesel engine. but when starting it knocks pretty loudly. Not like rod knock though. Not like any kind of bearing knock that I've heard. The knock goes away quickly, probably less than 30 seconds, heck, probably less than 15 seconds. I almost follow the starting procedure outlined in the operating manual: transmissions in neutral, full throttle, crank until it starts and then immediately reduce throttle to 1500 RPM. Where I deviate from the manual involves the decompression knob. The manual says to pull the decompression knob and crank the engine until it starts. But it won't start with the decompression knob pulled out. I suspect that the manual is wrong, that the decompression knob should be pulled out and the engine cranked until it comes up to speed, then released and cranking continues until the engine starts. After reading here about starting the Yanmar engines this is the proper procedure. But back to my knocking noise question. Is it normal for a Yanmar diesel engine to have a fairly loud knocking/rattling noise when first started which goes away in less than 30 seconds?
Thanks,
Eric
Thanks,
Eric
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