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44toy
01-22-2004, 09:10 PM
I bought a 18hp kohler magnum for one of my 52"bunton hydros. the seller threw in a 61" deck which the magnum was turning for $50. He said it would spin it fine but the mower never had sulky on it.
here is the question-the bunton now runs a 16hp v-twin vanguard with 52" deck pulling jungle wheels with my near 300lb but on them. On some of my yards the growth is thick and the mower will bog out and I have to nearly stop the mower to keep from killing the motor, thats why I got the magnum. So how much hp do you think I really need to turn the 61" deck? also how many rpms can you turn a magnum twin up to without destroying it. thanks in advance.

DennisF
01-22-2004, 09:30 PM
A 61 inch hydro would do ok with 18.. even pulling a sulky and 300 pounds. But It will bog in heavy wet grass. If your going to use a sulky and cut thick grass or set it up to mulch I would go up in HP...maybe 20 would fit the bill. Try it out with the 18 and see what happens. If it needs more HP you can always step up to a 20 or even a 23 Kawi. As far as turning up the rpm's, I had a 14 kawi on a 48 Scag WB a few years back that I "Tweaked" the governor on. I set the max rpm's at 4,200 (factory setting is 3,750) and it didn't shorten the life of engine, but it sure sucked fuel after that. It burned nearly twice as much fuel at 4200 as it did a 3750. The extra 450 rpm's at max throttle helped at little but not all that much. It might work better on a higher HP twin.

FrankenScagMachines
01-22-2004, 09:44 PM
3800 RPM is the highest I would go on a stock engine. 3900 if you really lack for power, but absolutely no higher. Of course it will shorten engine life. It's spinning more times per hour....
If you go over 4,000 RPM it can be dangerous. They are not made to operate at those speeds and can literally fly apart. Only adjust the RPM if you have a tachometer hooked up to it and do not bypass the governor, only adjust the settings for the governor.
If your 16/52 bogs, why do you think a 18/61 wouldn't? You've got 3.25" of cut per horsepower with the 16/52, and 3.38" of cut per horsepower with the 18/61. Therefore the 18/61 will have alittle less power than 16/52. It probably would work ok, but don't expect to blast right through tall stuff or run double blades.

44toy
01-22-2004, 10:30 PM
The 18 magnum will go on the 52 for now. and the 61" deck would replace a 48" deck on another bunton hydro I have for a backup now to try as a test on some of my yards to see if it will scalp,dig,etc. was gonna power it with at least a 20hp kohler maybe a 25hp kawasaki, depends on what I find. this is just a test, I am afraid even if it swings the 61 in dry grass wet dew in the mornings will clog the giant deck no matter the hp. the vanguard on the 52 is old and runing at just under 4000 rpm with a photo tech, I haven't even tached the magnum but it sure seems to run like it is only turning around 3000 maybe. I have never swung a deck this big on any machine I used regularly and only have a guess to the hp required to use one on a w/b and sulky with my big butt. thanks for the input and sorry for not explaining better. one more thing I have always heard the magnum series engine is the strongest engine ever built (most bang for the buck) anyone run the 18 magnum?

packerbacker
01-22-2004, 10:32 PM
The first problem is that your interested in a Kohler. Those motors are junk. The pull starts are almost completely made of plastic compared to a Kaw which is mostly metal. You will have problem after problem after problem with a Kohler. Save yourself massive headaches and go with a KAW

44toy
01-22-2004, 10:49 PM
Not trying to be an arse but I have had some 14hp kawasaki and 14hp kohler. The kohler would out pull two of the kawasaki motors. The kohlers have always been a little harder to start but the 14 koher I have will pull about as hard as the twin 16hp vanguard. this is the first twin kohler I have had but if it is half of what expect it will be a increase from the vanguard. I have heard a lot of good stuff about the kawaski engines but only had the 420s, they were not very impressive. Every one has there favorite and the kohler is mine for power. the kawasaki and vanguard are very reliable with good power.

packerbacker
01-22-2004, 10:52 PM
Not trying to be an arse





Yeah i know, i just never had any luck with them , it always seemed to me that they were built kind of shotty, lots of plastic pieces in them that cause them to wear down alot faster but i guess its like any piece of equipment, if you treat it right it will last a long time

44toy
01-22-2004, 11:03 PM
Thanks for the kind reply, saw you have a 36 and 48 I assume you they are w/bs . just wonder what hp you run and if you get in much wet taller (5" grass cut to 3"?) and I also assume they are kawasaki engines? do you run them or employees? also do you run vekly?

packerbacker
01-22-2004, 11:11 PM
Thanks for the kind reply, saw you have a 36 and 48 I assume you they are w/bs . just wonder what hp you run and if you get in much wet taller (5" grass cut to 3"?) and I also assume they are kawasaki engines? do you run them or employees? also do you run vekly?






Yes they are WB's. I run a 14 on the 36 and 18 on the 48. Usually if the grass is a little wet i dont change anything, if its really wet and its clumping, i usually just raise it up on the first cut and then go back over it lowered on the second. I do have a sulkie for the 48 but not the 36. I only use my 36 on 2 out of the 35-40 yards i do. Luckily 99% of houses dont have fences or the gates are big enough for a 48.

PaulJ
01-23-2004, 01:48 AM
Iv'e got a 23hp running a 48" deck so for a 61" deck I would want at least 26hp. I'd also put 20" tires on it.

rodfather
01-23-2004, 09:21 AM
Originally posted by PaulJ
Iv'e got a 23hp running a 48" deck so for a 61" deck I would want at least 26hp. I'd also put 20" tires on it.


23 hp on a 48? You brush hog with that machine Paul? Anyway, we run 23 hp Kawis on our 61 inch Ferris WB's and either 17 or 18 hp on our 52 inch WB's.

General Grounds
01-23-2004, 09:31 AM
:blob3: i own 4- 61" hydro walkbehinds and everyone of them has a 20hp kohler and have plenty of power even with the velky attched, you do not need a 26 hp motor on a wlkbehind, sorry.

J.Gordon
01-23-2004, 10:10 AM
Originally posted by PaulJ
Iv'e got a 23hp running a 48" deck so for a 61" deck I would want at least 26hp. I'd also put 20" tires on it.


I agree with Paul. I have a 25 HP on a 54’’ deck and I have bogged it down a couple of times when mulching deep leaves. But I am a power junkie!:D
Jeff

PaulJ
01-24-2004, 02:59 PM
Originally posted by rodfather
23 hp on a 48? You brush hog with that machine Paul? Anyway, we run 23 hp Kawis on our 61 inch Ferris WB's and either 17 or 18 hp on our 52 inch WB's.


Rod,

You know what machine I am talking about. If a 48" rider can have a 23 hp than why not a walkbeind with a sulky?

rodfather
01-24-2004, 03:26 PM
I agree with ya Paul.

Flex-Deck
01-24-2004, 03:42 PM
I agree with Paul also - I run 22 diesels, and I figure they will lug right along with 26 gas engines, and they do well with my 60-78" decks.

LawnMower
01-24-2004, 06:08 PM
the way I look at it, is if it bogs down all the time. Take the center blade off so theres less to spin. Wala problem solved.

DennisF
01-24-2004, 09:22 PM
Originally posted by LawnMower
the way I look at it, is if it bogs down all the time. Take the center blade off so theres less to spin. Wala problem solved.


Stripes?