Just bought a new Scag cub w/ 25 Kohler

Discussion in 'Lawn Mowing' started by skeet, Mar 30, 2008.

  1. skeet

    skeet LawnSite Member
    Messages: 166

    This thing is like a tank compared to my very faithful Woods 6180.
    I read that after break-in you change oil every 100 hours. Do you guys really wait 100 hrs? I guess i'm old school, I'll change at 50 hrs.. most, the oil is the life of the engine.
    What replacement oil filter do you use.. such as Fram 3614 ect? Need cross ref. for Kohler.
    I mowed once and am very impressed, it's built solid.
  2. grass_cuttin_fool

    grass_cuttin_fool LawnSite Gold Member
    Messages: 3,526

    I change at 50 hours and use a purolator L10240

  3. tb8100

    tb8100 LawnSite Bronze Member
    from TX
    Messages: 1,625

    nice choice! Alot of guys like to change at 50 hours. Definitely wait til then to change it. Then run synthetic! Being an air-cooled engine, it's going to be under lots of heat and stress. May as well run an oil less likely to break down under that kind of stress.
  4. nosparkplugs

    nosparkplugs LawnSite Gold Member
    Messages: 3,444

    don't wait until 50 hrs!!!! I change all equipment over to fully synthetic when I get the equipment back to the shop. You want to stop engine wear ASAP, the "break" in period is all butt "old School thinking". Most engine manufactures are using fully synthetics at the first start-up.
  5. tacoma200

    tacoma200 LawnSite Fanatic
    Messages: 5,426

    Most manufacturers recommend not using synthetic during break in. I've read the manuals and talked to the company's. On the other hand auto's such as the corvette come out with mobile one so go figure. I've been on this site a long time and almost everyone I've talked to agrees on waiting a while before going synthetic. I mean the engine manufacturers themselves have stated moving parts need to break in/seat properly before going the full synthetic route. I'm all for Synthetic, especially with air cooled equipment. If it's old school then some one needs to tell the engine manufacturers.

    In response to the original question, I change oil and filters after the first 5 hrs of operation as recommended by the manufacturers then I change oil/filters every 50 hrs even though most recommend 100 hrs. The first oil change at 5 hrs or so is probably the most important.

    Congratulations Skeet, hope you like you new ZTR.
  6. nosparkplugs

    nosparkplugs LawnSite Gold Member
    Messages: 3,444

    Most engine manufactures that are not recommending synthetics from the factory are going by the minimal API lubricant standards, these are bare minimal recommendations to pass, and no engine manufacture can require you to use a specific oil unless it is supplied free of charge.

    Under the Magnuson-Moss Warranty Act, 15 U.S.C. SS 2301-1312 (1982), and general principles of the Federal Trade Commission Act, a manufacturer may not require the use of any brand of product (or any other article) unless the manufacturer provides the item free of charge under the terms of the warranty.
  7. tacoma200

    tacoma200 LawnSite Fanatic
    Messages: 5,426

    I think your missing my point. They told me and I have read that it is best to run conventional oil and let the engine break in before switching to synthetic. Not because of any law, because they believe it needs to be broke in first. Your saying the company's are wrong! Your saying that is old school thinking and the company's are telling me it isn't. I have no proof either way, but I will take the company's advice. I'll put 100-200 hrs on them then switch to synthetic. I'm sure you are trained by Amsoil since you are a distributor and are knowledgeable. Please show me the paper work from Kawasaki, Kohler, Briggs etc that say they came out with synthetic oil from the factory and recommend using it from the start. I'm not saying your not right, I've never seen such statements in any owners manual or heard this from the major engine manufacturers.

    I don't care admitting I'm wrong I just want to see it in writing or from the three major engine manufacturers.
  8. nosparkplugs

    nosparkplugs LawnSite Gold Member
    Messages: 3,444

    In the vast majority of internal combustion engines which use reciprocating pistons, the pistons are surrounded by piston rings to create a relatively efficient gas seal between the piston and the cylinder wall. Thus, when a charge within the engine cylinder is ignited, creating high combustion chamber pressures, the expanding gasses which are formed during the burning process are confined to the combustion chamber. The confined gases exert a downward force on the piston and are not permitted to escape between the piston and the cylinder wall. Although the piston ring is typically captured within a groove which is cut along an outside circumferential surface of the piston, the ring is sized relative to the groove so that is free to move within the groove. It is important that the piston ring be movable (axially, radially, and circumferentially) with respect to the groove because its relative movement enables proper sealing to the cylinder bore as the piston moves axially and radially, and as the ring traverses distortion in the cylinder wall.

    There is a critical time period for new engines known as the break-in period during which the moving surfaces of joined components adjust to matingly conform to one another. During this break-in period the piston/piston ring interface is particularly susceptible to a condition known as microwelding, wherein there is a propensity for the piston aluminum to transfer to the sides (typically the lower flank of the piston ring.

    If during break-in, the piston ring can be kept free to move relative to the walls of the piston groove, and localized contact pressure reduced by merit of a relatively elastic material, the piston groove/piston ring will mate uniformly and microwelding will not occur.

    Micro welding, of the piston ring material, is what fully synthetics prevent during the first 50hrs of engine use. Why Kohler does not recommend fully synthetic lubricants at engine build is a company choice.
  9. jkingrph

    jkingrph LawnSite Senior Member
    Messages: 812

    My last two both of which I have were switched to synthetic at 5-10 hours, a 2000 JD LX277 lawn tractor and a 2006 Scag Wildcat LC Kawasaki 26hp. No problems, no oil consumption. The same goes for a 20 hp 12KW Honda generator.

    I'll continue to change my equipment to synthetic, as I also did on my F250 6 L Diesel.
  10. mowman84

    mowman84 LawnSite Member
    Messages: 91

    I change my oil every 50hrs on my kawaski's

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