lawnmower oil

Status
Not open for further replies.
What kind of 10W-30 do you run? I could understand a spec for 10W-30 for a few reasons. Number one, if you use conventional, the best 30w is a 10W-30... unless of course your could get a 15W-30 or 20W-30, would would be a lot harder to shear. Number two, it's always going to be somewhat warm or hot when you are mowing grass, so they know a 5W-xx is unnecessary. Possibly number three, they know the general public out here thinks a 5W-30 is water compared to a 10W-30. Keyword 'thinks'. Not saying YOU do that, or any of these, just making guesses.

I may be using 0W-30 (GC), but from what I just saw on a chart that someone put together on here, it appears GC at 40 degrees Celsius is thicker than a couple of 10W-30's, and thicker than most 5W-30's at that temperature.
 
It's my theory that a lot of 10W30 full synthetics actually have no VIIs, which mean they won't shear nearly as much. Considering the splash oiling and summer-only use - what's wrong with 10W? GC is particularly shear stable, typically OPE will eat 0Wanything for breakfast because of extensive use of VIIs.

Amsoil ASE is an example of a synthetic SAE30 with no VIIs, but also achieves 10W30 rating.
 
Originally Posted By: Craig in Canada
It's my theory that a lot of 10W30 full synthetics actually have no VIIs, which mean they won't shear nearly as much. Considering the splash oiling and summer-only use - what's wrong with 10W? GC is particularly shear stable, typically OPE will eat 0Wanything for breakfast because of extensive use of VIIs.

Amsoil ASE is an example of a synthetic SAE30 with no VIIs, but also achieves 10W30 rating.


In a splash oil lubrication system lighter viscosity oil tend to burn off quicker. One example is with the Delo400 10w-30 and the Delo400 30wt. Both are 30wt at operating temp but the 10w-30 tend to burn off quicker, noticeably in the early stage. I tried it once to see the difference .. it's a no go the SAE30 was the preferred oil.

The ASE is a SAE30 but can achieve a 10w-30 is colder temp conditions. By experience I do like the SAE30 in these small engines.
 
I mixed 2 quarts of Rotella T 10W30 with 2.5 quarts of Rotella T Synth 5W40. The 5W40 was free, but I didnt think I needed 15.5cst for a brand new B&S V-twin. So I made a nice ~13.9cst 10W40 blend with a good HTHS. :P
 
Originally Posted By: Mamala Bay
Originally Posted By: Craig in Canada
It's my theory that a lot of 10W30 full synthetics actually have no VIIs, which mean they won't shear nearly as much. Considering the splash oiling and summer-only use - what's wrong with 10W? GC is particularly shear stable, typically OPE will eat 0Wanything for breakfast because of extensive use of VIIs.

Amsoil ASE is an example of a synthetic SAE30 with no VIIs, but also achieves 10W30 rating.


In a splash oil lubrication system lighter viscosity oil tend to burn off quicker. One example is with the Delo400 10w-30 and the Delo400 30wt. Both are 30wt at operating temp but the 10w-30 tend to burn off quicker, noticeably in the early stage. I tried it once to see the difference .. it's a no go the SAE30 was the preferred oil.

The ASE is a SAE30 but can achieve a 10w-30 is colder temp conditions. By experience I do like the SAE30 in these small engines.


Several posts here and elsewhere have indicated that the reason isn't because it's "lighter" (have you read the spec sheet? Is the 10W30 variety actually lighter?), it's because of shearing. As the VIIs shear near the rings, for example, you're left with a 10 weight oil which moves right past the looser tolerances in these engines and gets "consumed". As it shears it is simply consumed instead of thinning the oil left in the case. If the 10W30 you chose was more shear stable, it may not show as much consumption.

Are the Delo400's you quoted dino, syn-blend or full-syn? All of the oils I discussed were group III or IV. (FWIW, my M1 10W30 OPE experience was when I believe it was still group IV, not whatever it is today). I'd expect M1, Amsoil and GC to be more shear stable than a dino variety, even if a diesel-grade.

All of the folks running GC in OPE should be a testament to that to some extent. At this time I only run it in my 27 years old snowthrower with an 8hp L-head - no consumption. I chose PAO straight weight in my summer OPE - no consumption.

The main point of my statement was that many *group IV/PAO* 10W30s *may* actually be VII-free, just like Amsoil ASE, but not be advertised as straight-weight 30s. There may be an opportunity to save money and get similar performance. Labeling M1 10W30 as M1 10W30/SAE30 would probably confuse the general public so they probably would never bother even though it may be technically true. I do not intend for that statement to be appled to non-PAO 10W30s.
 
Just spent over $5k on a new ZTR mower w/a 21 horse Kawasaki twin cylinder, dealer said to use castrol 30w, of course I am going SYN so what do you guys suggest?

PS-I picked up an extra oil filter and it appears to be an Oregon Brand and says "good filtration to 26 microns"...fwiw.
 
Last edited:
Originally Posted By: BayouTodd
Just spent over $5k on a new ZTR mower w/a 21 horse Kawasaki twin cylinder, dealer said to use castrol 30w, of course I am going SYN so what do you guys suggest?

PS-I picked up an extra oil filter and it appears to be an Oregon Brand and says "good filtration to 26 microns"...fwiw.


Go with what oil weight the owners manual recommends and not the dealer.
 
Originally Posted By: Craig in Canada
It's my theory that a lot of 10W30 full synthetics actually have no VIIs, which mean they won't shear nearly as much. Considering the splash oiling and summer-only use - what's wrong with 10W? GC is particularly shear stable, typically OPE will eat 0Wanything for breakfast because of extensive use of VIIs.

Amsoil ASE is an example of a synthetic SAE30 with no VIIs, but also achieves 10W30 rating.


I have a stash of Mobil 1 0W-40, I wonder if it would be fine to use it in my lawn mower which has a Honda GCV 160 engine in it. According to Mobil 1's website, they say that their 0W-40 can be used in automotive air cooled engines--would OPE place more demands on an oil than an air cooled car engine, or about the same? Here's their statement:

https://www.mobiloil.com/USA-English/Mot...led_Engine.aspx

Quote:
Question:
Oil Change Interval for Air-Cooled Engine
I recently discovered the new ILSAC GF-4 specs and realized that the Castrol GTX motor oil I have been using does not have the protective phosphorus and zinc like it used to and that my car needs. I meticulously care for my 1989 Porsche 911 Carrera.

It is a daily driver with 148K miles (I put about 12K miles per year on it). Because of this discovery I am about to switch to the Porsche recommended Mobil 1 0W-40 synthetic. Being an air cooled engine it takes almost 13 quarts of oil and each oil change is considerably more expensive with Mobil 1. (Wal-Mart has the lowest price for 0W-40 but they have an 8 quart limit for some reason.)

Questions: Should I use the 0W-40 or the High Mileage oils that are not of the same weight? (I live in Phoenix where it gets VERY hot during the summer) And what should the oil change interval be? I am thinking of changing it from 4 times a year to twice a year.
-- Kenneth Huff, Phoenix, AZ


Quote:
Answer:
Your engine will be protected with either Mobil 1 0W-40 or Mobil 1 15W-50, which should work for you at the intervals you mention.
 
Next oil change on my Honda GCV 160 will be with M1 0W-40...

Since it's a pre-owned engine, with no history other than neglect, I changed it with a mixture of 10W-40, 30W & 40W that was left in the bottles from adding to my old B&S that finally blew after 30 years... Hasn't used a bit of oil in a half dozen cuttings, I'll treat it to a better lubricant soon...
 
Status
Not open for further replies.
Back
Top Bottom