making diesel engine run quieter

HGM · Feb 20, 2006

( Hi I was wondering if anybody had any advice on getting my Case 685 diesel engine to run quieter. Although it seems to run good I find it to be loud. It is a 4 cylinder 60 hp with aprox. 4500 hrs on it. I don't know if the tappets have ever been reset or if that would even make a difference. Also I'm wondering if I can put an oversize muffler on it and what type I should use.
I've noticed to on most newer tractors that the engine area is completely shrouded and was wondering if that would help to reduce engine noise. Thanks )

Can you clarify the type of noise youre concerned about?

Exhaust noise can be muffled with a larger, or even different configuration of muffler..

Valve noise can surely be quieted by adjusting missadjusted valves..

Diesel "knock" can be due to incorrect injection timing, bad injectors, poor fuel quality, lack of fuel, and on and on and on........

Makes a difference... If theres nothing wrong and you just dont like the diesel sound, no theres nothing you can do.. Although you may want to try a fuel additive/cetane booster, to see if it helps...

IH3444 · Feb 20, 2006

More than likely an older direct injection engine. My IH BD154 engine is noisey. Setting the valve adjustment helped a bit, could put additional muffler on it. The direct injection engines are noisey just by the nature of the beast. Shrouds with muffling material will help also. Look under the hood of any modern day car, especially the diesel Mercedes, and Volkswagens. See that material attached under the hood. That the stuff you want inside your shrouds. Me? I just put ear plugs in, and go about tractoring. Must admit tho, the NH TC48DA is a quieter machine, but it is indirect injection also. Good luck! /forums/images/graemlins/smile.gif

Jagmandave · Feb 20, 2006

Why can't you just use the compression release so you can turn it over by hand (or with a wrench)?
Yes I realize you then have to release the release to adjust the valves, but it should make it possible to turn it over to the correct position to make the adjustments.

geneP · Feb 21, 2006

I have a CaseIH 385, little brother to your tractor, and it's noisy too. My exhaust is under the tractor and it's still noisy from the engine area. Using a C-tane enhancer helps the noise at idle some, but I think they are noisy by nature.

MMM · Feb 21, 2006

No such thing on this engine.

normde2001 · Feb 22, 2006

It totally depends on what is making the noise, exhaust, plain old diesel knock, or loose valves, (which you probably can't hear on a diesel tractor anyway for all the noise).

SailorBob · Feb 22, 2006

I can't believe it is any louder than a "Yammer Hammer". I guess I am just used to the noise. Although they do quiet down a bit after they warm up..

tkcomer · Feb 23, 2006

It’s exhaust noise. I have the 685 also. They do have quit a roar to them. Though no louder than a normal large four banger diesel with out a turbo. Take my DX-33. You can hear the engine on it. Not so with the 685. The exhaust drowns out any engine noise. But they have a pretty good size muffler on them. You can see here: http://www.pixagogo.com/7000025205 I bent mine back bush hogging under tree limbs.

SailorBob · Feb 23, 2006

Nice tractor. The exaust noise is not bad on a Yanmar but, the engine itself is. I have to shut it down or walk a at least 20 ft away to have a conversation with anyone. I have heard but, not tried it that you can hear better with ear plugs than without.

RobJ · Feb 23, 2006

( More than likely an older direct injection engine. My IH BD154 engine is noisey. Setting the valve adjustment helped a bit, could put additional muffler on it. The direct injection engines are noisey just by the nature of the beast. )

Interesting, i worked on diesels professionally for years. The direct injections were always quieter than the indirects (pre-combustion chambers). Always more rattle because you got sort of a double fire, once in the pre-cup and the other over the piston. Back then these were used in mines and the pre-cups put out less emissions. I think my L2500 is an indirect, haven't pulled the head but that's my guess.