Ran out thin as water !

[OtisBlkR1]

Last fall i put Valvoline Synthetic 5-30 in my 24hp B&S as the temp's were dropping and i was using the tractor for things other than cutting, i probably put 20 hours on that oil last fall early winter.

Ive had the tractor out cutting grass three times this spring so far and pulled the dipstick today before cutting and it was a little dark *I attribute this to doing some cleaning* Ive owned this tractor three years and only used SAE30 in it at all times. the straight 30 wt goes in pretty clear, comes out about the same. So i was pretty floored when black oil came flowing out of the tractor thins as water (Mind you the tractor was warm) but ive never seen any oil come out of anything than thin/soupy..

Im sure no harm was done running the 5-30 for 20-25 hours, and i am sure some cleaning was done.

thought id share.

 

[Nick R]

Those OPE twins are notorious for shearing oils.

 

[tommygunn]

Yeah, in alot of OPE I know even 10w-30 can have shear issues. I put 5w-30 dino in a lawnmower once that called for SAE30 figuring it would be fine.

Sheared it right down and burned alot of oil off before I wised up to things. I bet a 10w-30 synthetic would still be "stiffer" against shearing.

Straight 30 obviously is intensely robust.

 

[Nick R]

This is the reason I like HDEO for OPE.

 

[DP08GT]

Changed oil for the first time in my new honda gvc 160 engine.Had three hours on it,Oil was sae 30,it was black and like water as well.These air cooled engines just get very hot.

 

[OtisBlkR1]

Originally Posted By: Nick R
Those OPE twins are notorious for shearing oils.


Rotella Straight 30 HDEO went back in it today.. all is well in the world

 

[DockHoliday]

Thanks for sharing.

I have 4 single lung, air cooled engines that I have been feeding left over M1 0W40 from my cars. I have been wondering if I should go to the trouble of purchasing Amsoil's 4 stroke SAE 30 synthetic. I think I now know the answer now.

 

[Shannow]

There's nothing mystical about either the engine or amsoil that would make you need to spend on the latter.

If you want a straight 30, any number of them in dino, and even in synths, some "straight" 30s that also work 10W-30.

As to the OP, the difference in viscosity between "warm" and cold oil is massive, even without shear.

 

[Pablo]

Originally Posted By: DockHoliday
I have been wondering if I should go to the trouble of purchasing Amsoil's 4 stroke SAE 30 synthetic. I think I now know the answer now.

For sure the Amsoil will be more shear resistant than conventional oil. That said, of course hot 30 weight should drain out very quickly - but this isn't how viscosity is measured. Human apparent viscosity is just ball parkish.

 

[Cujet]

Mobil 1 5W-40 is a great choice for year round use in such engines. In fact, with this oil, I even extend the oil change interval to the maximum allowed by the manual. In my case, that's 50 hours.

 

[JTK]

Originally Posted By: Cujet
Mobil 1 5W-40 is a great choice for year round use in such engines.


Agreed, but IMO, that goes for any 5w40, not just M1.

I go the less expensive route myself and substitute 15w40 in place of SAE30.

Joel

 

[OtisBlkR1]

Originally Posted By: Shannow
As to the OP, the difference in viscosity between "warm" and cold oil is massive, even without shear.


Yes sir, obviously its going to be thinner warm, the point of my post though was just how thin it was coming out! Ive never witnessed oil come out of anything (even HOT) that thin. Im not making any claims here, just casual conversation and talking about my observations.

I did however find it intresting that ive used Conventional HDEO 30 for the better part of three years and even after 50 hours that stuff still looks almost brand new coming out of my B&S. I put SYN 5-30 in it and after 25 hours its Dark, Dark unuff you cant see through it. (yes color means little)

Just sharing guys, just sharing..

 

[JR]

In small OPE's i will run 15w-40 over 30wt, those being my first two chooses if they are setting around.

 

[SOHCman]

Rotella T5 10w-30 is also a fine HDEO for OPE.

 

[CaptainNed]

Also makes for a great substitute in the hydro tranny. T5 for the tranny & T6 for the engine.

 

[morris]

put water in youll get water out.

 

[kmrcstintn]

would a good quality 10w-40 motorcycle oil be appropriate? my yamaha v-star calls for 10w-40 in the manual...it is an air-cooled engine...just curious

 

[mount]

Originally Posted By: kmrcstintn
would a good quality 10w-40 motorcycle oil be appropriate? my yamaha v-star calls for 10w-40 in the manual...it is an air-cooled engine...just curious


You got it backwards. I'd be running a HDEO in your mower as well as a 15W-40 in your bike.

To answer your question, I guess it really depends on what kind of "motorcycle oil" you have. Most "motorcycle oil" is nothing special, other than its label.