Horse Power?

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So my kohler engine has a crack in the block I guess, so I'm going to replace the engine.
My engine is a 20hp but they said I could go up to a 23hp or maybe a 25.
I'm wondering if that little of HP would make a difference in water heat and cleaning ability?
Thanks
 

dgardner

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If you keep the same pulleys, meaning blower speed doesn't change, you won't really see any difference at all, except the new motor won't be running as close to it's max horsepower as the old one was, and may last longer because of it.
 
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Zee

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Gardner, just wait 'till Captain sees this .... He'll tell everyone the thousandth times about "more horsepower is better "..
 
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clean image

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well..depending how old you cracked engine is, there is new standards how they rate horse power, and it seams most have dropped ave 3-7% their rating

my 31 aegis is now rated 30
my 27 kawi is now rated 25.5

so if you get a new engine with same horses...you will be ahead (a little)
 

GeneMiller

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If you keep the same pulleys, meaning blower speed doesn't change, you won't really see any difference at all, except the new motor won't be running as close to it's max horsepower as the old one was, and may last longer because of it.
One thing to consider, engines are most efficient at a certain rpm. I recently found out that running on low on my engine burns more gas. It was only one tank so I still need more data. On medium speed I get 1.51 gph but on low I used 1.69. A bigger engine has a different power curve and may just end up being wasteful with no gain.
 

Mike Draper

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When you start messing with pulleys, you better know how to calculate the RPM ratio and and bunch of other details or you are more than likely going to open a can of worms. Id leave the pulleys alone, like Dan said, a little bit bigger of an engine wont be working as hard to turn things and will probably last longer.
 
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What size blower do you have???
Amen on the kero heater it will double your cleaning in some dirty applications.
25-30 hp for a # 4. Blower
30-35 hp. For a 4.5. Blower
35-40 hp. For. A 4.7 blower
Run those aircooled engines full throttle that's how they are designed to run.......
Cap
 

Mike Draper

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to each his own, but I wouldnt run any engine at full power if you want it to last a long time. I ran my judson 35hp at 2950 and it purred like a kitten with a 47 blower. RPM's dropped about 100 under heavy load. Just no need to run it at max if the engine hp to blower/ hp ratio's are in line.
 

dgardner

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to each his own, but I wouldnt run any engine at full power if you want it to last a long time. I ran my judson 35hp at 2950 and it purred like a kitten with a 47 blower. RPM's dropped about 100 under heavy load. Just no need to run it at max if the engine hp to blower/ hp ratio's are in line.

Agreed, but there are always factors to consider. Any engine run at absolute max power will have a relatively short life-span. Run it near the torque peak (usually several hundred rpm below the max-hp rpm) for good performance with reasonable life. Water-cooled engines have a better range of rpm and for the most part lower rpm will give you better life. Diesel engines have a very narrow rpm range, and require a minimum load to avoid wet-stacking.
 

dgardner

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Betting my pos 20hp works just fine.
I bet it does too.

Your blower needs about 13hp and the pump (maxed out pressure and flow) needs about 3.

Interestingly while your Kohler engine is rated for 3600 rpm they run it at 3000 - just like Mr. Draper suggests. I bet 3000 is pretty close to the torque peak.... ;)
 
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rjwood

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I bet it does too.

Your blower needs about 13hp and the pump (maxed out pressure and flow) needs about 3.

Interestingly while your Kohler engine is rated for 3600 rpm they run it at 3000 - just like Mr. Draper suggests. I bet 3000 is pretty close to the torque peak.... ;)
Do I understand this to mean HP above 16 isn't all that important? I use a 19hp Kohler - can I upgrade my blower? If so, what's the largest I can go?
 

dgardner

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No, you can't just add up the hp and select that size motor. For one thing the standard test for engine hp allows the mfgr to remove the muffler and air cleaner, so hp available to the end user will be less than advertised. And you can't run an engine at 100% and expect it to live long.

In Mikes case 16 hp load (approx.) On a 20 hp engine seems about right.
 

dealtimeman

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I was just joking.

For a slide in with a number 4 and a 3cp pump I think 22-25 engine seem to last the longest.

Today I believe most manufactures are designing 5-7 year machines in that category. In other words the machine is designed to last 7 years AND be retired.

No one has said anything to me just an opinion of what I am seeing in construction materials me build methods. In 5-7 years that machine should pay itself. Many times over.
 
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dealtimeman

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I don't like it when a machine doesn't have enough power to maintain factory set vacuum(hg) at full rpm AND THE VAC PORT IS BLOCKED OFF. REALLY BOTHERS ME.

I DONT CARE IF IT IS SET TO 13, BUT IT BETTER BE ABLE TO HOLD 13 IN A TOTALLY BLOKED OFF SITUATION WITHOUT BEING STRETECHED TO ITS MAX AND SHORTENING THE BLOCKS LIFE.
 
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