Method of calculating "engine hours"???

KrashnKraka

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Searching "engine hours" is proving fruitless in satisfying my
curiousity, so I ask.
Is there a "rule of thumb" used by manufacturers to determine actual
hours under "full load"?

Now hour meters are being fitted (standard) it has to follow
300 hours is 300 hours, by the book (warranty).
I read where one supplier offers 300 or 3yrs, whichever comes first,
I presume. Another offers a flat 7yr warranty...conditional no doubt.
300hrs on a 1acre lot in a > 12"/yr rainfall catchment has to work down
to near on 6yrs as warranty.
Yet I am reading where some time, or in some cases , a lot of time,
is being spent travelling. No real load, no "work".
The clock is still ticking, so just how does a true reflection of work related
time get calculated. Or is it the case always that 300hrs is 300hrs?


TKS for reading :)

KK
 

Shughes717

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Jun 12, 2014
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Searching "engine hours" is proving fruitless in satisfying my
curiousity, so I ask.
Is there a "rule of thumb" used by manufacturers to determine actual
hours under "full load"?

Now hour meters are being fitted (standard) it has to follow
300 hours is 300 hours, by the book (warranty).
I read where one supplier offers 300 or 3yrs, whichever comes first,
I presume. Another offers a flat 7yr warranty...conditional no doubt.
300hrs on a 1acre lot in a > 12"/yr rainfall catchment has to work down
to near on 6yrs as warranty.
Yet I am reading where some time, or in some cases , a lot of time,
is being spent travelling. No real load, no "work".
The clock is still ticking, so just how does a true reflection of work related
time get calculated. Or is it the case always that 300hrs is 300hrs?


TKS for reading :)

KK

The hour meter on my mower only counts time when the blades are engaged. It only counts time when the engine is under a load. Some brands set hour meters up to start counting time when the key is turned on. For instance a friend of mine purchased a hustler x one and accidentally left the key on when he stored it after mowing. His mower now shows almost 400 hours, when it actually has a little over 100 hours on the machine.

There is farm equipment that has two hour meters on them. Cotton pickers, for instance, have an hour meter for engine hours and a second hour meter for fan hours. That gives dealers and farmers an idea of how many hours are on an engine and how many hours are on the machine when the engine is under a load with the fan and headers turning. There may be a time in the future when commercial mowers have two hour meters on them.
 

cashman

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Don't know if this is the answer to your question that you are seeking, but this is how engine "hours" was viewed by a well known engine manufacturer back in the day. Hours were broken down into "duty cycles" as specified by one of the dominate engineering societies. And it shows how much more durable lawn and garden type engines have become over the past few years. Back in the day when just about all aircooled engines had splash type lubrication systems, an oil change was generally recommended about every 25 hours. With the introduction of pressure lube systems with oil filters, the oil change recommendation was extended and eventually went to every 100 hours by this manufacturers OHV engines. That was provided the operator used the recommended type oil and kept the oil level at proper amounts. It was also a convienence factor based on the theory that a homeowner would use his engine on average 100 hours a year. Hence only one oil change a year in theory. Durability wise, some of the older cast iron engines were built to a B-10 standard which in durability testing, all the internal components excluding normal replacement items like filters, ignition, and lube items, had to withstand a service life of 1000 hours in testing at engineering society standards. Many of the commercial lawn and garden engines now are built to a B-15, B-20 standard and beyond meaning that they have internal components that have been tested to withstand 1500, 2000, hours or more. Of course all that depends on several factors like the amount of routine maintenance that has been performed, conditions of use, and manufacturing conditions etc. Both the engine manufactures and equipment manufacturers have had to make a shift in the market to accommodate the new engines. It would be overkill and wasted expence to put a 1500 hour engine on a mower frame that is only designed to last 1000 hours in homeowner use. And they now can make 20 or more horsepower out of the same displacement that in years past, they struggled to make 12 horsepower out of. And they do it with less emissions and environmental waste than in the past.
 

Bob E

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If we are talking strictly about a mowing machine;

(Estimated mowing time in minutes X number of weeks mowed in a year X number of mows in a week X mowers age in years) / 60 = rough estimate of engine hours

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Mad Mackie

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Best way on power equipment is two hourmeters. One connected to key on for machine total time, the other connected to PTO on for machine operating time.
 

7394

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Believe my Toro manual says hours on the meter are only counted when operator is seated ( obviously wired into the seat switch ) but with engine running..

Which isn't accurate of 'working hours'. By that system I have only 14.2 hours on this year to date.

I agree 2 hour meters would be better.
 

KrashnKraka

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Joined
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Don't know if this is the answer to your question that you are seeking, but this is how engine "hours" was viewed by a well known engine manufacturer back in the day. Hours were broken down into "duty cycles" as specified by one of the dominate engineering societies.

Goes a long way to getting me thinking duty cycle is way more scientific than hit and miss
assumptions around variations in usage. Perhaps we might one day see speed transducers
on flywheels counting cumulative hours within the power band ...above idle and fast idle?

KK
 

KrashnKraka

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JBrzoz00

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No problem, I've seen guys use those on boat motors. I'll be getting one when I get a new mower soon. Glad to be of help.
 
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