YM 2620 Engine Noise

[RNF]

I bought a gray market Yanmar 2620 a few months ago. The engine had a rattle in addition to the normal thumping sound of a diesel. I thought it was because 3 cylinder engines just run rougher, but now I'm not so sure it is normal.

I checked for loose fittings, but everything seems to be tight. It seems to be coming from the engine itself. Is a rattle sound normal for this Yanmar engine? If not, what might be wrong, how serious is it, and about how much should I expect to pay to fix it?

 

[winston1]

Video possible? Maybe try something like this to course the sound? Search Results For "Stethescope"

 

[CoyPatton]

I bought a gray market Yanmar 2620 a few months ago. The engine had a rattle in addition to the normal thumping sound of a diesel. I thought it was because 3 cylinder engines just run rougher, but now I'm not so sure it is normal.

I checked for loose fittings, but everything seems to be tight. It seems to be coming from the engine itself. Is a rattle sound normal for this Yanmar engine? If not, what might be wrong, how serious is it, and about how much should I expect to pay to fix it?

In my opinion the 3 cylinder Yanmar had less of a hammer than the 2 cylinder. That said every diesel has a ‘rattle’ for a lack of a better term.

I would encourage a video or at least an audio file to be posted.
Also you should be able to find youtube videos of a variety of 2 cylinder and 3 cylinder Yanmar’s running to compare your engine sound to.

 

[Roadworthy]

Three cylinder engines are not inherently rougher. Since you got a new to you tractor try to find what grade and type of engine oil is recommended. I'd probably start with an oil change to the correct oil. If you can't find the recommendation, diesel rated 15W-40 is pretty commonly used. From there be sure there's nothing loose in the engine compartment. Perhaps a bracket has worked loose and is rattling from engine vibration. Try to get the opportunity to listen to other engines, especially Yanmar, say at a dealer. That should give you an idea of what is normal.

 

[winston1]

Yanmar 262D 4x4 Tractor with Bulldog FEL and Howse Brush Hog - YouTube

 

[RNF]

Thank you for the suggestions. I feel a little stupid for not thinking of that. There were a couple of YouTube videos where I could hear the Yanmar engine noise. They were similar to mine.

The only other diesel I have ever had was a 4-cylinder Perkins in an old Massey Ferguson. That one was a lot smoother and it made me wonder why the Yanmar seemed so much rougher. I thought there might be a problem with it.

 

[CoyPatton]

Thank you for the suggestions. I feel a little stupid for not thinking of that. There were a couple of YouTube videos where I could hear the Yanmar engine noise. They were similar to mine.

The only other diesel I have ever had was a 4-cylinder Perkins in an old Massey Ferguson. That one was a lot smoother and it made me wonder why the Yanmar seemed so much rougher. I thought there might be a problem with it.

I had a 4 cylinder Mitsubishi tractor several years ago and the additional cylinder over the Yanmar 3 cylinder was much smoother running. I assume that it is a more balanced motor with a cylinder on each of the 4 strokes. I have been around a couple of 2 cylinder Yanmars and was shocked at out noisy they were. It was my 1st experience with a 2 cylinder diesel engine. They were loud and made you think they were ready to come apart. Those are where as I have been told the term ‘Yanmar hammer’ came from.
In comparison my 3 cylinder 2002 is much smoother but not as smooth as that 4 cylinder.

 

[bmaverick]

Thank you for the suggestions. I feel a little stupid for not thinking of that. There were a couple of YouTube videos where I could hear the Yanmar engine noise. They were similar to mine.

The only other diesel I have ever had was a 4-cylinder Perkins in an old Massey Ferguson. That one was a lot smoother and it made me wonder why the Yanmar seemed so much rougher. I thought there might be a problem with it.

As you are in the upper north west of the country, diesel engine oil for winter is 5W30 and the hydraulic is J20D, especially in higher elevations over 1,000FT above sea level. Our Yanmars are basically close family kin to John Deere's of the same era of the late 70s into the early 00s.

Just the oil change and a tall oil filter can really help. AND because these are diesel engines, do NOT go below 30-micro filtration. Wix filters are great for petro vehicles, but poor flow for diesels. Purolator is in our flow range at 32 to 35 micron filtration for the oil. THIS HELPS KEEP THE ENGINE NOISE AND RATTLES DOWN.
You can use Rockauto.com for part look up on filters. 70% of the time the micro or flow rates are listed under the icon.

15W40 in the cold below 27F would make the knocking much more pronounced. Diesel 5W30 lately is getting harder to find as everything is going to synthetics. My next purchase may be the 5W40 as it's still diesel rated for winter use. However, it's not on the Yanmar / John Deere charts as our machines are vintage now.

Hope this helps tame the rattle and knocks. If the rattles are in the area of the oil pan, the crank bearings and races may be worn out. Something to consider. Like Winston said, use a stethoscope to listen on the pan and lower end of the engine.

Also, how many meter hours are on the machine ????

 

[RNF]

The hour meter was reset when it was imported, so I don't know the actual hours.

I'll try changing the oil.

 

[CoyPatton]

The hour meter was reset when it was imported, so I don't know the actual hours.

I'll try changing the oil.

Personally, if it is new to me, I consider a full fluid change to be part of the purchase price and process especially as I rarely buy from a dealer.
On these tractors like my YM2002D full fluids would be oil and filter, coolant and hydraulic fluid and a good cleaning of the screen (they are reusable/serviceable unless damaged. Hoye and others have replacements.)