FlyWheel Screen Grass Protector

[leeave96 487]

I saw one time on a Gravely tractor pic what looked to be a brush that set on the flywheel screen of a Kohler engine. I may have made a post of it - can't remember.

I was at a dealer today and they had a used Gravely rider and as you know the engine is mounted low and at the rear of the tractor, not unlike a VW bug.

Here is a pic of the brush arrangement that keeps grass from building up on the engine. I'm wondering if these are available for single cylinder (in addition to twins) Kohler K's and Magnums and more importantly the Onan engines.

[TT-(Moderator) 1,131]

I have seen single-cylinder Gravelys with that scraper/guard and It wouldn't be hard to build one.

The twins on normal Wheel Horses have guard screens that cover the rotating screen.

[Tankman 3,518]

Easy enough to remove the "newer" style plastic screen. I often take my off, wash 'n dry.

I also blow air through the fins after each use. I don't think I would want or need that "thing" shown on the Gravely (?). The 's engines are higher anyway.

On one Kohler which wasn't used for sometime, I had to clean out a number of fins which had been occupied by

mud wasps.

[leeave96 487]

I have seen single-cylinder Gravelys with that scraper/guard and It wouldn't be hard to build one.

The twins on normal Wheel Horses have guard screens that cover the rotating screen.

The problem I see - especially with the Onan's is that grass gets pulled onto the outer screen and stuck to it - like laying a piece of paper on the screen. The grass may be prevented from going into the engine, but it is blocking valuable cooling airflow into the engine. It looks to me like the scraper, for lack of a better word, would prevent this outer build-up.

[varosd 1,185]

My Onan really only has issues with the leaf season in regards to the screen of the flywheel. that is why I really use only the trusty old B-80! not sure how the gravely dohickey would prevent buildup...?

[TT-(Moderator) 1,131]

Onans have the biggest build-up problem because their cooling system was engineered for gen-set and welder applications. Chaff isn't much of a problem in those applications but lack of air flow is - so they are designed to move a lot of air.

Having blades of grass or a few leaves built up on the outer screen isn't much different than a passive HVAC filter, which doesn't reach maximum efficiency until it accumulates some dirt.

I watch the outer cover on my 416-H and if it gets too bad, I brush it off with my hand. It's pretty hard to do that with a Gravely while in use, so I can see why they have the scraper.

[Wheel-N-It 2,969]

Bill, you are Briliiant! I always enjoy the good things you post on RedSquare. I need something like this on my 417-A with the Kohler KT-17 series 2.

That old KT will suck up leaves and grass (and clog the screen) from the next County when I am cutting grass with it. You have given me an idea how to solve this problem, and I want to :text-thankyoublue:

[artfull dodger 396]

When I have mowed with Wheel Horses in the past, if I was spitting grass up on the engine intake side of the mower deck, it usualy ment there was an issue with the mower deck, either plugged up or missing an internal shroud that directed air flow. The only time I have personaly had issues with chaff build up on an Onan, was on a Sears not a WH, was when I mowed during a real windy day, and I was also covered with green chaff! As I see it, if your an attentive operator and see the screen getting covered with chaff, its pretty easy to lean forward and wipe it off with ones hand if you have the outer screen on that doesnt rotate. Keeping the rest of the motor clean and free of oil and other sticky goo to me is more important, then the chaff that gets past the screen, just gets blown out the other side nornmaly. But if there is sticky stuff in there, then the chaff starts to build up. Mike

[Wheel-N-It 2,969]

Actually I was thinking of making one that uses something more like a broom, not a scraper.

[dbartlett1958 96]

This scraper would be useless on the Onan with the plastic guard in place as nothing is turning to move the debris past the "scraper". If you had a different engine with a rotating flywheel screen, then it could be helpful. JMHO.

David

[leeave96 487]

Actually I was thinking of making one that uses something more like a broom, not a scraper.

Van - I don't think that is a scraper, but rather the jig (for lack of a better word) that holds a small brush against the flywheel screen.

Thanks!

Bill

[Whmaverick 54]

Looking at the angles , I wonder if it acts as a fan only in reverse as the angled blades are fixed but the air being drawn past helps to inhibit the debri build up? Just a thought.

[varosd 1,185]

OK, I'm not the only who can't figure how the rig works? is it supposed to use a squeege attachment like some sterno bum on the side of the road.

[mrocket49 23]

We have those on our Gravely walk-behind tractors at work and I always thought they were to help prevent your leg from hitting the rotating flywheel screen. Ours never had a brush-type attachment on it.

[Save Old Iron 1,566]

onan? sterno bum? that is what we need - a windshield wiper like mechanism to sweep away the debis

[TT-(Moderator) 1,131]

Seriously - they are nothing but a scraper.

The adjustable plates are set at a certain distance from the rotating screen, When the debris build up thick enough to contact the scraper, It 'wipes' the entire screen clean.

Too bad the Onans can't have reversible fans like some of the new turf equipment:

[BOWTIE 226]

I DON'T THINK IS A SCRAPER. I BELIEVE IT THERE TO PROTECT THE SCREEN ITSELF. REMEMBER THE MOTOR IS OUT OF SIGHT. I LIKE THE IDEA OF BRUSH OR SOMETHING FOR ARE KOHLER WHEEL HORSES. HERE IN OHIO WE HAVE COTTONWOOD TREES FLYING IN THE AIR. THEY ARE LIKE DANDELION FUZZIES. WHEN YOUR MOWING YOU REALLY STIR UP. I SOMETTIMES STOP AND BRUSH THEN OFF WITH WHISK BROOM.

BOWTIE IN OHIO

[Save Old Iron 1,566]

Something like this

a thin pancake motor mounted on axis with the air grill - driving a carbon fiber "broom" with a slow speed motor activated either by the operator or on a timer every few minutes ??

another option would be a 4 leg "broom" with a radial return spring underneath the air grill - the operator would pull a handle on the dash mechanically connected thru the shroud to the pivot point of the broom. the broom rotates 90 degrees with the cord pull, then returns to home under spring tension.

or the broom is connected with a gear on the shaft of the broom - operator pulls a small lever connected to a gear rack - the broom moves in accord with the operator pulling and pushing on the assy connected to the gear rack.

paint everything black to make it visually unobtrusive

some mechanically minded individual could surely make a useable prototype from one of those ideas

[varosd 1,185]

sounds great Chuck!

sorta like those windshield wiper delay switches that we had to get from JC Witney to add to my 72 Nova! I really just get loads of leaves, during the Fall, and have to lean forward to manually scrape them off.

[Sean Szpila 0]

Flywheel screen rotates as the engine runs, you adjust the smaller plates in towards the screen, get it close enough without making contact and it will scrape/squeegee the debris off as you run it.