Lawn Tractor Oil help

[twistedfinn]

Hello everyone. I have a 25 hp White Outdoors (Tecumseh) dual carb, ohv engine on my lawn tractor. The owners manual says to use SAE30 and to change every 25 hrs. Also specifically states NOT to use 10w40.

I'd like to switch to a synthetic, but, have had no luck finding any in a straight 30. I'm not familiar enough yet with syns to conclude what to use on my own. Also, at what interval should I change it out? Would 75 hrs be reasonable? This is where you guys come in!

This engine runs year round (hook snow thrower up in the winter) is air cooled and currently has about 135 hrs on the clock. This is its second season. Last year put about 100 hrs on it.

Your help is most appreciated!

Mark

 

[MONKEYMAN]

I use Mobil 1 10w-30 in my parents rider with good results. I change it once a season or close to 50 hrs. By then it is really black. Maybe the "experts" here can give more specific recommendations.

 

[Ugly3]

I saw somewhere that Briggs & Stratton has approved full synthetic 5w30 for their small engines the year around.

I have run Mobil 1 5w30 in my 18HP lawn tractor for maybe 6 years now. Don't get too many hours on it (maybe 60 hours) so I change once a year in the spring. There is no oil filter on my unit so I try to err on the safe side.

 

[KW]

Most 10W30 synthetic oils are a 30 weight oil. They use very little if any VI's because the oil naturally acts like a 10W30 in cooler temps.

 

[1maniac]

Amsoil makes a Synthetic straight 30 weight and the have a 0w-40 Synthetic 4-stroke oil. I personally like the 0w-40 because my mower starts easier and doesn't consume oil compared to the 30weight.

 

[Bill Kapaun]

Dual carb????

If you peruse the motor oil section of this forum, you'll see why 10W-40 isn't recommended. Basically, it has too many Viscosity Index Improvers compared to say 10W-30.

Personally, I'd change the oil & filter every 50 hrs. or so. This would allow you to use one weight of oil for summer and a thinner weight for winter.

 

[Bror Jace]

I think the recommendation against 10W-40 oil is a bit dated. Early formulations had VII problems but I wouldn't hesitate to use it now ... although it's not my first pick in weights for this or most other applications.

I use 15W-40 in all my lawn & garden equip. It is a good weight for heavy-duty use (although not too heavy to cause over-heating and loss-of-power) and will still be a solid 30 weight even if they shear a little. Best of all they have strong anti-wear and detergent/dispersant additive packages to protect air-cooled motors and keep them clean. If morning start-up is not much of a factor, it's a near-perfect weight.

I liked Pennzoil Long Life 15W-40 best among the big brands before they took the moly out of the formula (although old batches on the shelves will still be good). All brands in this weight are good, but I suppose Chevron Delo400 would be my 2nd mass-market choice after older Pennzoil L.L.

I use Schaeffer synthetic blend in 15W-40 right now, changing it once each year in the fall after about 60-70 hours of miscellaneous use.

Ugly3, I'd do your once-annual oil change in the fall instead of the spring so your motor's internals are stored while immersed in fresh oil instead of contaminated used oil. Although, if you are giving your tractor annual oil changes, you are already doing better than most owners out there.

Try searching this forum using the word "tractor" for more discussion from the recent past ... and even a couple used oil analyses (UOAs).

--- Bror Jace

 

[Bill Kapaun]

quote:

---

Originally posted by Bror Jace:
I think the recommendation against 10W-40 oil is a bit dated. Early formulations had VII problems but I wouldn't hesitate to use it now ... although it's not my first pick in weights for this or most other applications......

--- Bror Jace

---

It might be a bit dated, but still true to a lesser extent.

Personally, I feel if I need a 40 weight, then the temperatures are warm enough that I don't need a 10W, and vice versa.
I've been using 15W-40, but next change I'm going back to 10W-30. By the time the temperature is in the 90's, my lawn is so brown I don't mow anyway.
In the early Spring, where the temps may be in the 40's, the 15W does make starting a bit tougher than a 10W. That's when my Honda needs 2 pulls instead of 1 to start.

 

[MolaKule]

As most people know, I use Schaeffer's #700, a 15W40 for the really hot summers here in Do-Dah land.

However, if you can't get Scheaffer's, try this simple mix for a heavier 10W30.

1 - 5 Qrt. Bottle of Mobil 1 10W30
24 oz. of Mobil 1 Truck and SUV 5W40.

I believe it is B&G that basically says it is ok to use a 10W30, but you should use a synthetic 10W30.