Proper dual blade installation on this Honda mower, and a few other questions.

[MowerMark]

This mower is about four years old. A year ago I removed the blades and asked a mower shop to sharpen the blades ($15). This time I decided to sharpen these two blades myself when there appeared "mohawks" (see below). Found this hand held carbide device for $8 on line. Three rubs to each edge and twenty seconds later the blades sharpened nicely. Sweet! After reinstalling them, not sure I put them back properly but at least the sharpened edges contact the grass first. The grass now has a clean cut edge on examination of the cut blades.

PROBLEMS:

1. There's a slight clicking sound as they rotate, but it's getting less

2. The grass still "mohawks", that is despite mowing the in the usual pattern done in past years, often a very narrow band of taller grass remains. It was this "mohawking" which prompted my sharpening these blades. Sharpening maybe reduced it a little. What causes this ?


I looked on-line and at the manual, and all it states is to put them back the way they were installed. Duh. I didn't pay attention. Where may one find a picture of proper blade placement ?

* As a separate question, how best to clean the underside from all the grass accumulation ? Wooden stick ? Spatula ? Is it okay to spray water in the area when the mower is on its side ?

* And yet another question. I enjoy using AMSoil Synthetic products in my car (260,000 miles). May I use AMSoil 10-30 Synthetic oil in this mower ?

* I've heard debates on blade sharpness. How important is it for these blades to be sharp, and how sharp should they be ? The lawn mower professional who sharpened the blades a year ago said that the blade need not be sharp to cut grass.

Thank you,

Mark

 

[pile81]

The blades kinda fit together, the bigger of the two on bottom. As far as cleaning the deck, tip on its side toward the exhaust, and spray out with a pressure washer or just scrape clean. Now for the "lawn professional" who said the blade does not need to be sharp to cut the grass is true BUT it doesn't really cut it, it bludgeons it. A sharp blade is essential in keeping grass alive and healthy. Dull blades cause yellowing (dead tips) so keep your blade sharp and it will keep your lawn healthy and green.

 

[lawn mower fanatic]

I agree. :thumbsup: See the post below I copied from an older thread to show what I use to clean the mower deck.

I just wanted to post back in this thread to tell you what I use now. I got a new putty knife when I bought my Honda HRX mower that is made especially for cleaning mower decks. It works better than the one I had (the one on the left in the picture) since the new one (on the right) has curved edges.
View attachment 11665

I would be scared to use a pressure washer because there is the possibility to get water where it shouldn't be, but that's just me. Blades should be sharp, but not overly sharp, just not dull.

 

[lawn mower fanatic]

Blade goes like this:

http://www.lawnmowerforum.com/membe...s-maintenance-picture15790-twin-blades-3.html

 

[robert@honda]

There's a slight clicking sound as they rotate, but it's getting less

Double-check and make sure the blades, bolts and special washers are correctly installed. Carefully inspect the gap between the blade tips and mower deck and see if the blades have been striking the mower deck or contacting somewhere.

The grass still "mohawks",

Confirm mower height settings. Confirm blades installed correctly and sharp. Try lowering front OR rear wheels one click. Try mowing when the grass is a bit shorter. Mow only dry grass.

Where may one find a picture of proper blade placement ?

Depending on the model, blades will be stacked right on top of each other, or offset just a bit. Here are two examples:

When installing the blots, use a torque wrench and tighten to the spec for your mower. Share the serial number off the back of the mower deck (MXXX-1234567) and I can direct you to a copy of the owner's manual where the blot torque spec is published for your exact mower.

How best to clean the underside from all the grass accumulation ? Wooden stick ? Spatula ? Is it okay to spray water in the area when the mower is on its side ?

Let the engine fully cool off before cleaning. Hot bearings expand, allowing water to get trapped inside and will rust. For a Honda mower, tip the carburetor/left side UP. If you tip the muffler/right side up, it will leak fuel and oil will foul the air cleaner.

May I use AMSoil 10-30 Synthetic oil in this mower ?

Any type of SAE 10W-30 is fine, synthetic or petroleum-based. Do not buy into the argument you can extend the change interval with synthetic, however. Always change the oil per the maintenance schedule (usually 50 hours, 25 if used under heavy load or very hot >90ｰ F environment)

How sharp should they be ?

Not "razor" sharp. They will quickly dull. Sharpen at about 30-40 degrees, and the edge itself should be about 0.1-0.3 mm (0.004-0.012 in) thick

 

[MowerMark]

Thank you, Robert of Honda !

Some clarification questions please.

1. From where did you get those blade depictions ? I couldn't find them.

2. The center nut seems to do nothing on my mower. Is doesn't hold either blade in place. Is this correct or is a part missing ? What does this seemingly useless nut do ?

3. Do you approve of a water stream cleaning in the underside pan if and when the mower is cool ?

4. Is there a spray one may use on the clean metal to help prevent adherent grass cuttings ?

5. RE: 10-30 motor oil, would this be the same oil type I've been using in my Toyota Sedan ? Or does one use "small engine oil" ?

6. When buying new Honda replacement dual blades, are they pre-sharpened or must one sharpen them first before installing ?

7. Are replacement bolts available ?

 

[robert@honda]

1. From where did you get those blade depictions ? I couldn't find them.

Shop manuals...they are available from Honda (paper only) via eBay or Amazon.

2. The center nut seems to do nothing on my mower. Is doesn't hold either blade in place. Is this correct or is a part missing ? What does this seemingly useless nut do ?

The big nut in the middle holds on the blade holder, but not the blades. The big nut does NOT need to come off to remove the blades, just loosen / remove the two outer bolts and special washers.

3. Do you approve of a water stream cleaning in the underside pan if and when the mower is cool ?

Yes. Avoid spraying water on the engine directly, but under the deck is just fine.

4. Is there a spray one may use on the clean metal to help prevent adherent grass cuttings ?

Not that Honda recommends. A good cleaning after each mowing is best medicine.

5. RE: 10-30 motor oil, would this be the same oil type I've been using in my Toyota Sedan ? Or does one use "small engine oil" ?

SAE 10W-30 is a the same as what you'd put in a car. Just fine to use an "auto" oil for your mower. Just make sure it's marked "SAE 10W-30" and you'll okay.

6. When buying new Honda replacement dual blades, are they pre-sharpened or must one sharpen them first before installing ?

New blades are already sharpened from the factory.

7. Are replacement bolts available ?

Yes, have the serial number off the mower deck when shopping, as all parts lookup systems need that number to match the correct parts to your mower.

 

[MowerMark]

The Honda replacement blades from Home Depot seemed quite dull so I had them "professionally" sharpened before use. Was this not advisable ?

My model number is HRR2167VKA and serial MZCG-822xxxx. Honda's website was confusing because that "7" was missing from the model number: Honda Lawn Mowers: HRR216VKA, HRR216K8VKA

Is this the wrong link for my mower ?

Please suggest that Honda put the blade pictorials in the owner's manuals.

(BTW, it's impressive how this mower starts with the first cord pull.)

 

[exotion]

The flat blade without wings goes on top of the two blades. To sharpen take an vice.grip secure the blade to the table and an angle grinder make a nice smooth shiny surface using the factory angle. Razor Sharp is nice but you need to sharpen more often (I do because I have the time)

On my hrr a screw that holds the sheet metal belt cover came off close to the chute that piece of metal got sucked into the blade I needed to resecure it that was the clicky sound on mine.

I also recommend the micro cut over the quadrant cut blades because the quadrant cut just sucks

 

[MowerMark]

The flat blade without wings goes on top of the two blades. To sharpen take an vice.grip secure the blade to the table and an angle grinder make a nice smooth shiny surface using the factory angle. Razor Sharp is nice but you need to sharpen more often (I do because I have the time)

On my hrr a screw that holds the sheet metal belt cover came off close to the chute that piece of metal got sucked into the blade I needed to resecure it that was the clicky sound on mine.

I also recommend the micro cut over the quadrant cut blades because the quadrant cut just sucks

Thank you. Do you have a picture or diagram of that HRR screw area ?

Not sure if my has a micro cut or quadrant cut. How does one distinguish and are both these blade types acceptable on my mower model ?