Not worth the trouble. Does your mower have the 'Quadracut dual blade set-up? If so, take off the upper blade. Make sure the lower blade is sharp and the deck is clean. Set engine RPM to the top of the allowance. Cut grass before it grows more than a half-inch. Cut it in the afternoon after it dries out from morning dew.

Thanks for the advice saxman.

It does have the quadracut system. Are you saying removing top blade makes mowing more efficient?

Unfortunately with my schedule (sell cars and work 50-60h per week) mowing is relegated to mainly Sundays or if the schedule allows, Thursday. I use a lawn care company to fertilize/treat for weeds/etc and where I live (St.Louis MO) in spring my grass can grow .5" in a day.

Say I could get the 190cc motor for ~$200 what would I need and is it pretty much a direct swap?

This is pretty much a last resort option. I am actively searching for a nice used Honda mower with Rotostop, hydro propulsion, 190cc motor as purchasing a new one is a tough pill for me to swallow. Also the current line of Honda mowers has the ~$600 model only with the smart drive (which I'm not familiar with and not too sure I want) and no blade stop system so I would have to spend ~$700 to get the hydro propulsion and blade stop system.

I really like the practically infinitely variable speed control with the hydro system as well as its overall simplicity and lack of components which to me means reliable. Blade control is just a nice feature IMO. And of course the 190cc engine.

Mow a narrower swath if you can't mow as frequently as you should.

Again, thanks for the comment but I'm already over cutting roughly 6"-8" into the previously cut row. I'm telling you, my grass is strong. Very thick and healthy as a horse.

I was slightly happy to read many reviews by owners stating the same complaint I had (leftover clippings behind cut areas/mulching action not efficient enough, having to remow to eliminate unmulched grass, pretty much a general lack of cutting performance/mulching efficiency in even slightly damp/thick/healthy lawns) as it reassured me that this used mower I had just bought had nothing wrong with it but that it was just the nature of this machine.

From reading I have done I believe that the extra power/torque the 190cc offers would more than accommodate my lawn conditions even when faced with wet/over grown or even both at once.

So has anyone done this or does anyone know what this swap would entail?

Thanks.

Here ya go.

Here is a link that might be useful: Engine specs

Thanks for the link on the engines but I was not able to get a definitive answer from that page.

I guess no one has done it...

From What i have found here are some differences.

The 190 is 8mm taller, 190 is 5.1lb heavier, 190 had .8 more hp and 1.4 more ft/lb of torque and thats about it.

Not sure if the 5mm increase in height is due to the block (not sure if thats the correct term when taking lawn equipment) being slightly larger to accommodate a longer stroke but thats the case with modular ford engines that im familiar with like the 4.6 and 5.4.

It would be great if I could get a junk 190 to try to fit it up the the 216.

Have you checked to see if the mounting bolt patterns are the same.

About the dual blades; what I found with mine was not a deficit of power, but the dual blades created 'green slime' that choked the deck and had to be manually removed from the wheel tracks before it killed the grass. After removing the upper blade, I found that I got normal mulching.
You are going into this thing with a 'mindset' that you intend to change out the engine regardless of anything you're told. That would be a stupid, expensive mistake. You didn't say that you had done a single thing I suggested, and now I'm thinking you're simply trying to cut 'too much' grass and believe you can solve it by throwing another 0.8 horsepower at it. Most people cut too much grass at one time by waiting too long and then cutting it too short.
I have two 6.5HP mowers, one of which has the Honda commercial GSV190 engine, and I still have to use my head when mulching under adverse conditions to avoid clumping, by raising cutting height, taking a half row and waiting for grass to dry some. Everybody has to do that - it doesn't matter if you have 25HP - you still can't exceed 3600RPM.
I think you need to learn how to use the premium mower you have and forget about the small power gain.

To answer your question, if the bolts match up, it can be done. Heck, even if the bolts don't match up, you can drill new holes and get it done.

No way would I mess with that project, though.

I suspect somewhere in the manual, they don't recommend mulching very tall grass.

Speaking of blades-
Are yours SHARP?
Dull blades are like throwing away 1 HP, IMO.

Yes, I have. I used a 190cc engine from a broken pressure washer. I put in a new crank. The flywheel from the pressure washer had the balanced larger crank, which is better for the engine.
I did not need the brake assembly because it would not work on the larger flywheel. I purchased a stop switch from Boats net and it works fine. You will not have the welded nut for the switch, but a longer screw and a nut works fine.
Anyway, I got a new pressure washer motor for $20 the new crank cost $25. The switch cost $7.
The engine with the larger crank runs very smooth and idles like a champ. I can cut grass at low speed and it has plenty of power.
And the HRT runs better that it ever did. I am going to do another one soon.

Can't believe I found this thread on page 2! Guess I never hit the email notification from this site!

Saxman, I appreciate your insight but to be honest if I had the knowledge and will to swap motors on the HRT it would be rational thinking to assume I tried everything else. Never did I say I didn't, correct?

I ended up finding a brand used (I said it!) HRX217HXA and what a machine it is! The very first time I cut my grass with it I hasn't mowed in 3weeks and with the height all the way up, I was cutting ~8" of grass off the top. Not only that but it rained the entire previous day and only stopped raining some time the night before when I was asleep. I cut at about 10am do no time for the lawn to dry. It was the epitome of the test I was looking for and on 100% mulch, there was barely a blade left to speak of! I was more than satisfied and actually very impressed with the cut quality in the given conditions.

I still miss my HRT though from time to time. It was a ber nimble mower that could be tossed about with ease. Not so with the HRX, it's much more substantial and has roughly 20lb or so more bulk to contend with.

Now I can cut my grass whenever I need to and need not worry about over cutting or stragglers left behind!