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fitzg2md
08-15-2007, 09:11 AM
I do it also, but does 50 hours or so seem like a very short interval for changing oil? I know the engines co. recommend this, and so I believe them/do it. The reason you do oil changes is to get rid of the oil "used up" oil right? If so, wouldnt it seem like this oil is capable of more than 50 hours of use?

Does anyone know the operating temp. of say a 27 pony kohler air cooled? My only idea is than these engine run far hotter than car engines, and the oil breaks down faster. On the right track?

PS- I agree that 5 bucks in oil every once in a while beats the heck out of 2k for a new engine!

MarcSmith
08-15-2007, 09:28 AM
I did 100 hours but used mobil one... FWIW

ALarsh
08-15-2007, 09:56 AM
I do it every 100 hours with mobil one.

hess
08-15-2007, 01:50 PM
Every 50 hours

causalitist
08-15-2007, 02:18 PM
100 hours ... amsoil synth.

if amsoil recommends 25,000 miles in cars.. there is no way it wheres out in 50 hours lol.

its about the dirt/dust our engines are subject to. and for that reason, i think concentrating on the absolute best air and oil filtration is the key to using these oils potential

lawnspecialties
08-15-2007, 03:49 PM
100 hours + Mobil 1

Always done this and never an oil related problem in 8 years of LCO.

delphied
08-15-2007, 04:07 PM
I think my Kohler manual says every 100.

All_Toro_4ME
08-15-2007, 04:42 PM
Mobil 1. Every 100 hrs. Never had a problem.

sjessen
08-15-2007, 05:06 PM
I use Wal-Mart oil and change it every 25 hours or once per week. But, I only change the filter every 200 hours. I've got 2500+ hours on a Kaw 23 with no oil related problems.

hess
08-15-2007, 06:15 PM
I use Wal-Mart oil and change it every 25 hours or once per week. But, I only change the filter every 200 hours. I've got 2500+ hours on a Kaw 23 with no oil related problems.

why would you put fresh clean oil in with a dirty oil filter?

topsites
08-15-2007, 06:16 PM
I change it when it gets to looking a certain color, don't care much about the interval itself thou that is a nice guideline and usually on target, but there are times it needs changing before, other times it can go a ways longer. It helps to learn this, it can prolong both the life of the engine AND the oil change interval, but it takes time, the recommended interval is usually a fail safe method.

The Wb's, once or twice a year, all depends, they can and will sit during off-season without an oil change.
One reason I dislike calls for work requiring an off-season machine, one reason I charge extra for it also.
You dang straight it costs a LOT of dollah to get me to do leaves in April, especially if I have to pull the big blower on wheels!

Synth always, there's no question about it, I could probably run it pitch black down to a quart and the engine shouldn't seize.

Here's the color when it needs changing now IMO:
(this was, amazingly enough, after only 2,000 miles, I gave it an engine flush, this color I don't normally get until 3,500-4,000)
IF it's any darker it's too far gone, but so long it doesn't leak a once / week check does it for me.
Once it gets like this, change it n.o.w., the reason I keep oil and filters in stock.

Skyking
08-15-2007, 08:42 PM
100 hours ... amsoil synth.

Ground Scapes
11-18-2007, 10:12 PM
I use Wal-Mart oil and change it every 25 hours or once per week. But, I only change the filter every 200 hours. I've got 2500+ hours on a Kaw 23 with no oil related problems.

are you retarted! First why would you waste your time and money changing the oil every 25 hours? Also why would you put clean oil in a dirty oil filter? doesn't add up

only change the oil every 100 hours along with the oil filter

daveintoledo
11-18-2007, 10:45 PM
oil is cheaper then metal....

adrianrog
11-18-2007, 11:31 PM
Guys,

I work for a Cat dealer and we have an oil lab. Find a lab to test your oil, you'll find that it's no where used up when you're throwing it away, especially if you're using synthetic. We have customers with over-the-road trucks running oil 100,000 miles. They're changing filters every 10,000 miles and topping of the oil.

My Kawasaki manual recommends every 100 hours and I figure the engineers that designed it know what they're doing.

As an interesting side note, we had a call come into field service the other day for a wheel loader that was running rough and had no power. When the field guy got there, it was obvious it hadn't been maintained properly. When he asked for info on the machines maintenance, he was told that they'd never done anything but put gas in it. He thought we were supposed to maintain it. Anyway, almost 5300 hours on the original oil, filter, fuel filter, air filter, etc. The engine is toast at this point, but for what they saved on maintenance, I guess they can buy a new one.

-Adrian

N.TX
11-19-2007, 12:32 AM
Should be changing the filter every week not the oil

Richard Martin
11-19-2007, 04:40 AM
I do what the manual says. Pennzoil 10w30 every 100 hours and a new Purolator oil filter every 200 hours in my Kohler engine.

shepoutside
11-19-2007, 06:21 AM
Yes, a lot of manuals say 2:1 oil:filter changes, but filters are so cheap, so why not change them too. Would you skip a oil filter change in your car? You would use a 30 weight oil too, never seen it say 10W30.

MarcSmith
11-19-2007, 06:30 AM
I agree I'd change Filters before the oil.....all it takes is a few pieces of the paper element to break away and clog an oil hole.

FWIW. I went 100 hours filter and oil, in my cars I go 10K between changes...

delphied
11-19-2007, 07:12 AM
One thing is sure. You wont hurt your engine by changing the oil too much but if you change it too little, you can hurt it. Same with the filters.

txgrassguy
11-19-2007, 09:58 AM
Oil lubricates through the suspension, actually a colliodal solution, of different additives that when subject to heat suffer from a process known as thermal breakdown.
The amount of time this takes to occur is based upon the thermal diffusivity of the different types of oils, their additives, and the environment the machine operates in.
Bear in mind the crankcase capacity of a typical small engine is significantly less than an engine for an automobile. This capacity is what what helps keep the breakdown from occurring more rapidly in larger crankcase capacity motors as more oil equates to a more efficient cooling cycle.
So, in effect, the oil "wears out" faster in smaller capacity crankcases meaning it has to be changed more frequently. Also remember when the oil loses it colliodal ability, the additives are no longer performing their intended function. However, the filtration of the oil is usually not affected as rapidly unless your operating environment is unusually harsh.
This is why filters are changed on a 2:1 basis to the oil.
I have spoken at length with field engineers about oil change intervals and what these guys told me is their recommendations stem from research with their material engineers evaluating the motors' life expectancy through oil sampling and analysis - hence the ratio.
As far as the operating temperature, the primary wear occurs not in the crank but in the cylinder heads which is why the cooling fins have to be kept clean of accumulated gunk.
As this material accumulates it actually decreases the surface area for the heat to disperse from which in turn raises the temperature which in turn lowers the life expectancy of the oil.
How I deal with this when maintaining the 20+ machines in my crews fleets is to set a specific day for maintenance.
The cooling fins on everything is brushed clean, debris blown off of the frames, the motor itself is cleaned then the change out occurs.
A benefit towards cleaner motors is obviously the increased service life but with the reduced operating temps the motor will use less fuel so the cost per hours is less as well.
In my case this translates to the ratio as recommended although those in cooler climates can extend this interval to over 100 hours easily.
I have started buying oil in 55 gallon barrels and throughout one year will use three barrels. The cost savings over case quantities is significant, essentially halving my oil related costs.

BFLL
11-19-2007, 10:04 AM
oil is cheaper then metal....

For the moment anyway..

MarcSmith
11-19-2007, 10:06 AM
For the moment anyway..which begs the questions...if oil is going up in price. shouldn't synthetic "oil" be cheaper...I wish...

Richard Martin
11-19-2007, 07:15 PM
You would use a 30 weight oil too, never seen it say 10W30.

Kohlers have been using 10w30 since I've been buying them. It's right in the manual. I think the last motor Kohler built that used straight 30 was the old K engine.

JamesGarfield
11-19-2007, 10:00 PM
All of these comments about oil change invervals appear to be for the engines with positive pressure pumps and oil filters.

What about the lower end motors with slinger lube systems and no filters?

Yes, I know, not really commercial grade... but the book calls for 25 hours
on these, and I think that's way too long for that enviornment.

tomo
11-20-2007, 01:25 AM
I do it also, but does 50 hours or so seem like a very short interval for changing oil? I know the engines co. recommend this, and so I believe them/do it. The reason you do oil changes is to get rid of the oil "used up" oil right? If so, wouldnt it seem like this oil is capable of more than 50 hours of use?

Does anyone know the operating temp. of say a 27 pony kohler air cooled? My only idea is than these engine run far hotter than car engines, and the oil breaks down faster. On the right track?

PS- I agree that 5 bucks in oil every once in a while beats the heck out of 2k for a new engine!

Hello,
##air cooled run very hot and very uneven temps through out the engine###

typical med to heavy load walker[52 deck and up/ 25hp same engine as yours just 2 less hp] mower sump oil 125--140celcius 255--285f
No oil company i have contacted recommends constant running over 212f / 100c for extended periods
All oils degrade just some faster than others
The full synthetics particularly mobil 1 will be best etc for the heat but not for **dirt capacity** . Remember most of the mower engines only hold 2 quarts . The conclusion would then be to change oil more frequently as eg kohler suggests in dusty conditions . From that deduction using full syn oil is a waste for 50 hr intervals $$$.Part syn would be fine .If u operate in clean conditions mobil 1 at 100 hr intervals would be ok

Always change filter on mowers due to the oil/dirt retained in filter being of such a large quantity compared to pathetic sump capacity .

Another point on air cooled temp ,remember that the same type of engine may run in the snow country so the original design is always going to be compromised

tomo

Richard Martin
11-20-2007, 04:15 AM
Always change filter on mowers due to the oil/dirt retained in filter being of such a large quantity compared to pathetic sump capacity.

The next time you take a oil filter off I want you to open it up and see what's inside of it.