HNV Comparison (Harshness, noise and Vibration

[pfrederi 17,739]

HNV is a big deal for car manufactures and there are engineers totally devoted to it.  They have all sorts of equipment to measure it..  I only have my senses but there are differences in WH models.  The last couple days were intensive mowing days.   Used three different machines and there are, to my senses, some big differences. Worst was the recently overhauled K-341 on a Charger. Following the frequent remarks here I left out the balance gears.  There is a very strong vibration and after an hour so of mowing you hands are getting tired.  The vibration brings out lots of secondary sheet metal noises. (I never ran this engine before the overhaul so I can't compare before/after). Next test was a Magnum 16 mouthed on a Charger.  Vibration was much less, still noticeable but hands didn't feel as tired after mowing for almost 3 hours.... I have never opened this engine and I doubt any previous owner did either so it has its balance gears.  Last test was C-141 again I doubt the engine was ever molested so it still has balance gears and the shaker mounts.  (Rubber is only in fair not great shape).  She was much more pleasant that the other 2...Still am not a big fan of the isolation mounts but they do seem to work. Next big block overhaul the balance gears are going back in with new bearings.  Yeah some failed but most last a long time, at 71 I don't need 40 more years out of them.  i am convinced some of the reasons they are left out is the hassle timing them...i bought the tool so we shall see on the next project...

 

 

[ebinmaine 67,498]

2 minutes ago, pfrederi said:

there are, to my senses, some big differences

I'd say that's true with lots of machines. 

The last few years I've noticed my forearms, and hence my grip, can't take the vibration they once did. 

 

My own C160 does fairly well. It has the thicker type steering wheel. 

 

The Charger hydro is horrific. 

Because I have to keep adjusting the speed constantly I can never let go with either hand. Left steers. Right controls speed.  After an hour or so it's very tiring. 

 

Another very noticable one for me is chainsaws. 

The old Sachs Dolmar I had was THE absolute BEAST. 

I could only run it for 20 minutes and my hands would begin to feel fatigued. 

 

[Maxwell-8 4,275]

20 minutes ago, ebinmaine said:

The old Sachs Dolmar I had was THE absolute BEAST. 

Jonsereds really got ahead of it's time as to vibration in the chainsaw world. If you get your hands on a new Stihl. they feel like an accordion.

 

I heared those Onan's or Kohler 2 cilinders vibrate less.

 

 

[ebinmaine 67,498]

11 minutes ago, Maxwell-8 said:

heared those Onan's or Kohler 2 cilinders vibrate less

Agreed

[squonk 41,118]

I wonder if a "Comfort Grip" steering wheel would help? 

 

You have a pic of the timing tool Paul? Just curious what's involved.

[ebinmaine 67,498]

5 minutes ago, squonk said:

Comfort Grip" steering wheel

Is that what's original to a '77 C160?

[squonk 41,118]

4 minutes ago, ebinmaine said:

Is that what's original to a '77 C160?

Don't know. My 76 had the hard plastic one like the ones Paul posted in his pics.

[squonk 41,118]

Another thing that would help even though they would be hot are Mechanix Wear impact gloves.

 

[Maxwell-8 4,275]

32 minutes ago, squonk said:

"Comfort Grip" steering wheel

400 an 500 series WH had softer steering wheels at one point

Or whatever they mean by "Soft feel"

Edited May 20, 2021 by Maxwell-8

[pfrederi 17,739]

My C175s are much smoother.  I even did away with the isolation mounts on them.  Haven't had the one set up for mowing out yet this year she is fixed up for the cyclovac. But they also have the thicker steering wheel which I am sure helps.  The K341 vibration is so strong you can't read the instruction label on the PTO mount when it is running.  To help with the ancillary noises I am converting her to an Electric PTO  see if that helps reduce the noise...She is only going to be used for mowing and the harsher engagement of Electric PTOs is not as big a deal for that.

 

Picture is the timing gear alignment tool.  The Original Kohler one was plastic.  This is a metal repro.

 

 

Edited May 20, 2021 by pfrederi

[squonk 41,118]

I wasn't having any vibration issues. But the thicker wheel is better for my Arthur Itis. 

 

[lynnmor 7,306]

Harbor Freight had anti-vibration gloves for many years, I use them while running my old Homelite chainsaws with good success.  The didn't last real long because the padding would go flat and become less effective. but they were cheap and they worked.  I thought that some might find them useful but they no longer appear on their website.  I have one new pair left plus my old pair that should be retired.  I guess HF only wants products that don't work.

[Stepney 2,325]

My 1957 Economy with the big thumper 7hp B&S just about bounces the tires up and down at a idle.. 

I have a old utility K301 which I was the first to run out of it's crate, basically. No balance gears.. Its a single, sure it feels like a single. But I'd hardly call it a shaker. The 414-8 motor in my WorkHorse, an older K321, shakes quite a bit. The thin metal and plastic wheel helps nothing..

But I used to have a Raider and a Charger 9, both with the 10hp Teccy..

Those would rattle your teeth out at any speed. 

Have a big K341 in my Electro, no balance gears.. quakes a bit but I expect that out of a single that big. Still miles better than newer machines.

 

On the subject of saws..

Anyone ever run a Wright gas reciprocating saw? I've got one, opposed piston 2 cycle.. THAT shakes, boy..

My 1980 Echo 602VL is a massively overweight, rubber cushioned behemoth.. feels like holding an electric saw.. maybe anemic but it is quite easy to handle. 

 

I always find shaft driven machines smoother no matter how they were built. My 60's Cubs always had a 'hood shimmy' at idle but you never felt it in the wheel or the seat. 

[roadapples 6,983]

1 hour ago, ebinmaine said:

Is that what's original to a '77 C160?

All 3 of my 74s have it...

[JoeM 7,874]

Having arthritic issues and have moved into the more modern power steering machines. Toro 522xi and a Kubota GR2010. There is a world of difference. All around less tired and most comfortable to operate. 

Every now and then I would take a turn with an older machine, kind of nostalgic, but I like the newer ones. 

[kpinnc 12,055]

3 hours ago, pfrederi said:

  To help with the ancillary noises I am converting her to an Electric PTO  see if that helps reduce the noise...She is only going to be used for mowing and the harsher engagement of Electric PTOs is not as big a deal for that.

I added a "soft start clutch controller" (google search) to my Scag's electric clutch, and it is much easier on both the engine and belt. Works for Ogura and others. Uses the single wire wrap on the spark plug cable to engage the clutch with pulses matched to the speed of the engine. About $60 when I got it. 

[Tuneup 1,433]

I have that same copy muffler you do and the output does not point forward like the original so you're getting much more sound. My 125 is so much louder than the 120 with the 125's old muffler. You might want to shop for a bathroom drain pipe to cover the output and point it proper. I've been wanting to do this and have next week off so...will do something to stay busy.

[pfrederi 17,739]

13 minutes ago, Tuneup said:

I have that same copy muffler you do and the output does not point forward like the original so you're getting much more sound. My 125 is so much louder than the 120 with the 125's old muffler. You might want to shop for a bathroom drain pipe to cover the output and point it proper. I've been wanting to do this and have next week off so...will do something to stay busy.

So you put an e bow on it so it aims forward??? Have you a picture that is a great idea....

[Tuneup 1,433]

I'm king of the procrastinators. I'm actually going to make a measurement and will hit Ace next week. The 125 needs to get some sun and I'll have 40 extra hours. Stay tuned

[bds1984 1,429]

When I hear of people talking about cars having NVH they more often don't have a clue about what they're talking about and are just parroting something they read in some online article.  Most cars now have minimized those characteristics quite a bit compared to 20-30 years ago and are really only noticeable at 5-6k RPMs.  I just roll my eyes and suggest to them to drive a Citroen 2CV half-way across the country and then get back to me on what they think about a vehicle's NHV.   I had a Ford Focus with the 3-cylinder engine and by all accounts, that engine should have been ripe with NVH, except it wasn't.  The only time it'd be noticeable is at a traffic stop where the auto-start kicked in.  That engine is well balanced for what it is and smooth running all the way up to nearly 7k.  

I must be completely oblivious to the vibration of the shaker mount engines or all of mine have had mounts that are somehow still fully functioning.  My C165 is sans balance gears but still has the rubber mounts and the only time I really notice any vibrations is at idle and when I kill the ignition.  At operating speed the engine is quite smooth, even after operating my rototiller for two one-hour stints last week I didn't feel fatigued in my hands at all.  Perhaps I just got lucky and/or perhaps the steering wheel off a Toro 325D helps absorb vibrations.  My Kohler twins are buttery smooth no matter the mount style.  

 

[EricF 589]

On 5/20/2021 at 3:00 PM, Maxwell-8 said:

I heared those Onan's or Kohler 2 cilinders vibrate less.

Opposed twins are definitely smoother. First one I ever owned was a Briggs twin in a Bolens "Suburban". So much smoother than a single-cylinder motor. The big Onans are pretty smooth until they start working hard, and then you can feel the power strokes hitting fairly hard, although a lot of it may be the very strong exhaust pulse; the sound will echo off solid surfaces like gunshots. But it's still softer than a typical single. Don't know how the newer V-twins are. They all seem to have such a strong droning exhaust sound it makes me wonder if they're as comfortable to work behind as the old opposed twins.

[Maxwell-8 4,275]

25 minutes ago, EricF said:

Opposed twins are definitely smoother. First one I ever owned was a Briggs twin in a Bolens "Suburban". So much smoother than a single-cylinder motor. The big Onans are pretty smooth until they start working hard, and then you can feel the power strokes hitting fairly hard, although a lot of it may be the very strong exhaust pulse; the sound will echo off solid surfaces like gunshots. But it's still softer than a typical single. Don't know how the newer V-twins are. They all seem to have such a strong droning exhaust sound it makes me wonder if they're as comfortable to work behind as the old opposed twins.

Some of these V sound like harleys. 

 

[Maxwell-8 4,275]

I don't mind the sound off our small engines, for sure not if they sound great and my neighbors don't start complaining. But the vibrations, it something I have been thinking about doing something against it. My newly acquired C, has rubber engine plate mounts. But it wasn't the best idea as they are know to shred belts.  But what could we do? What putting pieces of rubber floormat between the block and frame reduce engine vibrations? 

 

If we can't reduce the vibration from the engine to the chassis, we have to a dress the 3 contact points between us and the frame: steering wheel, seat and foot boards/paddle.  

[Lee1977 6,659]

On 5/20/2021 at 3:30 PM, ebinmaine said:

Is that what's original to a '77 C160?

My 1977 C-120 had the rubber steering wheel and the 312 has the same style wheel.

[Tuneup 1,433]

Blast! The prices today are obscene! I hit Home 'Crappo' for a few things and priced a steel drain pipe as an exhaust redirect down like the original. Alas, the muffler outlet is a perfect 1.5" as is the chrome attachment. No fit. At $11, I won't even try. The old C-125 got an oil change and some ZDDP but no chrome redirect.