Farm Pro 2425 Engine Knock

[Bob Rooks]

Is the Y385T a direct or pre-combustion chamber engine? I don't know myself, but a pre-chamber engine will always exhibit loud knocking combustion noises (ever heard a Cat D-399?). A dribbling injector always magnifies that sound and you will get a greyish smoke from the exhaust, meaning unburned fuel. You might want to consider sending your injectors out to have them pop tested, cheaper than buying new I think.

 

[Bob Rooks]

60°C (140F) seems a little cool.

Definitely too cold. That creates sludge and won't even boil the moisture out of the oil, and subtract from any thermal efficiency. It needs to be bumped up at least another 40°F to 180°F. 190°F would be better yet. If you change the thermostat you will notice a difference in the way the engine sounds, particularly at thermal equilibrium, and it will seem like you gained a few extra ponies.

 

[piper184]

looking at the picture in the first post I would guess it to be a pre-combustion chamber. I have no other knowledge of the specs. It isn't described in the manual

 

[Bob Rooks]

I looked at the pics again and the cylinder head pic reveals that it is a pre-chamber engine. The #2 cylinder on the head is very wet and the cylinder liner is scored underneath the pre-chamber port, which tells me that a dribbling injector has washed down the cylinder walls of the oil film causing piston ring contact (and maybe a broken ring or two). Expect lower compression and excessive blow-by, not to mention poorer performance and premature engine failure if not repaired. Sorry.

 

[thepumpguysc]

Good eye, Bob Rooks.. I too enlarged the pics & see the #2 w/ several "score marks" running down #2 cyl. bore & the head wet..
If u could take a pic of the injector, where the line hooks to it.. I'll let u know if I can help u out..{pop test injectors}
I just broke one of my specialty lines, helping out another member.. So IF its not "that line" I'd be happy to pop test them for u.. TPG

 

[thepumpguysc]

IF ITS EASIER, send the pic to my home email..
Click on my screen name, left hand side of page.. that will get u to my PM page w/ contact info..

 

[IH3444]

Direct injection, loud noise, almost sounds like a slight rod knock, indirect injection with a pre-ignition combustion chamber muffles the noise and runs quieter.

 

[Bob Rooks]

Direct injection, loud noise, almost sounds like a slight rod knock, indirect injection with a pre-ignition combustion chamber muffles the noise and runs quieter.

Stand between a 60 Series Detroit and a 300 Series Cat and tell me what you think. Or if you like Internationals stand between a 7.3 IDI and a T444E (Powerstroke) and tell me what you think. And you are welcome anytime to stand between my Jaing Dong TY395E in the dozer and the Yanmar 4TNE in the skid steer and tell me what you think. Here is a short video I took of a direct injection engine while doing a valve lash hot set. Let me know if you hear a combustion knock.

EMD 16-71�G - YouTube


Here's another direct injection engine ................

Sulzer 12RTA96C: a walk around world's most powerful reciprocating engine, running at 7 rpm - YouTube

 

[piper184]

Bob,
The pre-combustion chamber is I would guess the oval opening in the head. What is the small round hole for?

Is there a way to detect a leaking injector short of pulling the head?

 

[Bob Rooks]

Bob,
The pre-combustion chamber is I would guess the oval opening in the head. What is the small round hole for?

Is there a way to detect a leaking injector short of pulling the head?

Yes. The oval opening is the pre-chamber port. I can only speculate on the small hole without seeing the head, and not being familiar with that particular engine, but I would guess it's maybe for a glow plug - however, glow plugs are usually installed into the pre-chamber.

Fuel injector pop testing is part of any responsible maintenance program, and is usually scheduled after so many hundred operating hours. Think of it like back in the day when you cleaned and tested your spark plugs every 7,000 miles and just replaced the bad ones. Most diesel shops have pop testers. Member here "thepumpguysc" can do it. It's not necessary to remove the head. On the 16 cylinder 710 EMD's the eco-tip injectors run around $400 each so they get changed out automatically every 30,000 hours. Also, the quality of fuel plays a huge role in the life expectancy of an injector.