Oil Viscosity Question

[roneil]

Will running a small engine (12hp Cast Briggs), with multi-vis oil do damage vs straight 10W30? I have a boatload of Castrol 20W-50W and am wondering if it would be OK or cause problems. Thanks, Bob

[dogboy]

I have the same situation, lotsa 20-50, but going by the advise in this forum and Briggs & Stratton, i bought the tractor its own straight 30 weight, the motor is almost 40 yrs old, don't want any problems using the wrong oil this late in the game

[andy gartner]

The Briggs site surprisingly, also recs. a 5w-30w synthetic eg mobil1 -running it in all engines, even my 30 year old 8hp Briggs, they purr like kittens now. Seem to idle better, less engine noise.

[stumpy]

Oil is much more important in air-cooled engines than in the water-cooled variety, partly because of localized heat patterns, oil's cooling qualities, and partly because of the tolerances required to allow for metal expansion, etc., due to that heat, simply put. One of the reasons straight-weight oil used to be reccommended exclusively was the fact that multi-vis oils tend to break down rapidly under the highly adverse conditions air-cooled engines impose. That, combined with the fact that most people (especially the average lawnmower owner) don't bother to change oil regularly in their equipment, if ever, (no one on this list, of course <G>) results in extremely short service life for air-cooled equipment. If changed regularly the multi-vis is likely just fine. My stuff is all solid iron...I'm sticking with good, ol' straight 30 weight...maybe straight 20 if I was somewhere in the zero-sub-zero temperature ranges. Back when I was flying old airplanes with round (radial) engines, I ran AeroShell 120 (straight 60 wt.) in the summer and AeroShell 100 (50 wt.) in the winter. Used oil out of the same barrel for my old iron-annie Harley at the time. None of that multi-vis stuff for those old radials. Had to buy it by the barrel too...those babies like their oil. In the words of my at the time quite ancient aviation mentor..."Son, I only worry about them birds leakin' oil when they QUIT leakin' it."

[roneil]

My 12HP Briggs is at least 35 years young ( in a 67-68 Sovereign). I also have a Briggs 14.5 OHV in a tractor brand that I cannot name in order to avoid ridicule (It's Red ). Thanks for the input. Bob

[patrician12]

Are there any 35-40 year old Kohlers still running ?Desides that I use straight 30 Mobil Delvac.Mobil calls it the million mile oil.It is for earth movers and stationary equipment that runs for days without stopping.You're not suppose to use it in passenger cars because the zinc content is so high it call wipe out a catalytic converter in a single bound.I use it in my high mileage cars and I will tell you oil consumption is eliminated and over time has desolved alot of oil carboniztion in the upper end.This winter it was really cold and my tractor with the snowplow on it wouldn't start.It just wouldn't crank fast enough.I drained the crankcase which took over a half hour,it was cold!!!Put 10w30 Mobil synthectic in and it started like summer.I do believe that above 40 degrees Briggs doesn't want synthetic in the engine.

[andy gartner]

Friend has a large equipment co. (dozers, backhoes etc.) Buys synthetic oil by the 55 gallon drum. Claims the diesels and gas engines (on even his older stuff) work much better, burn less oil, run much smoother, especially in winter, for starting. Because I am lacking when comes to changing my oil regularly, he suggested I go to synthetic, and give my engines a chance. In the winter, he also uses Slick 50 which I have never tried (as I think it may be just an STP clone, but with a zinc additive-which could be good, according to Stumpy, "the ancient aviator." Ya, I flew too, Stumpy-learned on J-3 Cubs, Cessna 150's, well over 30 years ago, while in my mid-20's). If my engines blow, using synthetic, I'll be sorry! But what the heck, you know, before we get old and rigid in our thinking, us young guys like to stay open to the possibilities and try things. Kind of "failing to success," sort of thing. So, when we get old, we can tell tales,' and impart a veritable plethora of information to the young'ens. We only hope, in the words of H. Melville, from his book 'Moby Dick,' we don't use that line too often, "There she blows!" A

[andy gartner]

Andy and Bob, There have been many discussions about oil on this site. One fellow even spoke of, how great aircraft engines looked after running on synthetic oil. A mechanic friend of mine, in Maine, who's used synthetic for 10 years, told me the TV ads that ran engines WITH OUT oil, after using synthetic oil, are real. Synthetic properties are exceptional. We all, do the research, talk to friends, get advice from this site, make decisions. 'Seems', there are few questions about synthetic oil's benefits, winter or summer, other than PROHIBITIVE costs, especially for those with many engines. (A lots cheaper by the 55 gallon drum). I run it in my 40's K-5 trucks, Farmall H,M's, JDeere A twin Cyl., Ford Naa, and antique motorcycles. For some, they've decided, 30 wt. detergent is the way to go. Good decision. If I had a boatload of 20-50w Castrol, I'd use it up in the SUMMER ONLY. If you're worried, change it more often. If my remarks seem frivolous, do your research, and go with what 'seems' most comfortable and rational for you.

[andy gartner]

Bob Check out the Briggs site, under "Types of Oil." There is only ONE type oil, recommended "at all temperature" From -20 degrees to 100 degrees F.

[MPH]

I've run Mobil 1 10w30 in my B-112 for 3 years now, still needs the ring job it needed when I found it, but the rod hasn't come out the side using it in the winter time yet..MPH

[stumpy]

Andy, Agreed on all points...the synthetics are great. Some folks (again, the average bear, not list members) seem to think it lasts forever...a dangerous assumption <G>. Everything Keith mentioned about the straight 30 wt. Mobil Delvac is correct...the stuff is great for older engines, in warm weather anyway <G>. Oh yeah....I'm not the "ancient aviator"....my boss was...ex WWII flyer he was...great guy, taught me a lot, but slightly deaf from all that noise over the years. Me, I'm just a young pup.

[Steell]

By the way, Briggs did an evaluation of Slick 50, their conclusion? Only put it in the motor of some one you dislike. The report is floating around the web, have to see if I can find it again and link it. Steve This one will have to do for now: [url]http://www.dragnbreath.com/dragnbreath/tn2aboutoiladditives.html[/url]

quote:

---

*Regarding the University of Utah Engineering Experiment Station testing Petrolon additive with PTFE. "There was a pressure drop across the oil filter resulting from possible clogging of small passageways." Oil analysis showed that iron contamination doubled after using the treatment, indicating that engine wear increased.

---

[andy gartner]

Hey Steve, Welcome aboard. Great link! Found Briggs study in a Yahoo search. Seems there 'may be' another additive that works called "Genesis," which is not a teflon based product like a slick 50. Anyone ever hear of it? Fred Rau "Road Rider" magazine also did great research on oils, synthetics, additives etc. He research says, forget additives, and on synthetics, Synthetic oils are excellent, and do work, but, are 'overkill,' unless you want that extra, "unnecessary" peace of mind. Now there's an anomaly. He favors, mfg. spec'ed oil, changed regular. Thanks again A

[Steell]

Been here awhile, just not real talkative:D Just hated to see someone ruin a good motor:( Steve

[andy gartner]

Steve Thanks! Been lucky so far, in the motor dept., but there's always room to screw up. And don't worry about not being talkative. I'm probably, full of enough hot air, to cover for you. A