I'm pretty sure the Lawn Queen used the 321 engine. My Lawn Queen is a 1952, and it's supposed to use a 16:1 ratio of 30 weight motor oil, not 2 stroke.
It's not that it's "supposed" to use 30 weight oil. It's that there was no 2 cycle oil back then. Good 2 cycle oil is much better to use in any 2 cycle engine than 30 weight.
Thanks for the history lesson about 2 stroke oil. I didn't recall that bit from my earlier research on my Lawn Queen, but that's what the manual with mines says, and that's good enough for me. Thing is older than I am, and still running, so I'll stick with the 30 weight.
Another fellow with lots of experience with the 321 engine of that era had this to say over on Smokstak:
"Fuel-oil ratio was 16:1 (1/2 pint SAE 30 - non-detergent oil to a gallon of regular gas) 2 cycle engine oil was not being made in the 1950's like it is today. I would rather see the SAE 30, than the modern 2 cycle oil, as the Lawn Queen engine is a low speed engine."
Guess you can find anything that supports your notions on the internet if you look long enough.
Kungdrew's greens mower might require different oil, so maybe getting an age on it and a manual, if he doesn't have one, would be helpful. If it was made before 1975, he might be able to find more on it here.
http://hmfind.com/JAC/JacobsenSerialNumberFinder.aspx
I read somewhere that using SAE30 will require you to decoke the motor at pretty constant intervals. Using the 2-stroke oil will reduce this.
It's very similar to oil buring steam locomotives and diesels. They had to decoke them pretty regularly. It 's messy and time consuming.
Yep, I've read that too.
Yes, depending on how often you use the machine you will have to de-coke the muffler/exhaust manifold, exhaust ports and the head because the 30 weight non-detergent oil does leave carbon build up.
Modern 2 cycle oil of today is far supperior in many many ways to the old school way of mixing non-detergent oil with the fuel.
The fact though is that these vintage Jac engines are plain bronze bearing, slow speed running motors and need the lubrication that the 30 weight oil provides. You can run the modern two stroke oil all you like in these machines, but be ware that by doing this that it will very potentially cause premature wear and that to me alone is simply not worth the risk to loose some smoke and carbon build up.
Here is brief run down that a friend of mine gave me a while back who has a lot of experience with these engines specifically:
" The modern 2 stroke lubricants do provide superior lubrication to modern engines. Engines with hardened bearing surfaces, rollers, balls and chrome molly rings, along with steel cylenders, and High speed - up to 22,000 RPM. The Jacobsen Lawn Queen, and the 321 series, as well as all those before are definately NOT modern They have soft bronze rods and bearings, cast iron rings and cylenders, plain bronze crank bearings, and for the most part, only turn 3,500 RPM Maximun - LOW SPEED! The 2 cycle lubricants do not stay on the bearing surfaces long enough to provide full protection. If you take apart an engine run with the modern lubricants, you will find a dry crankcase - there will be no oil on the bearing surfaces. for roller and ball baerings, this is not an issue, because the lube just has to be there a split second to do its work. On a plain bearing, this dryness is lethal! Plain bearings need oil on both sides to provide non friction issued. direct contact between metals brings on shearing forces that will tear the bearings up. While a roller-ball bearinged engine will tolerate a leaner oil mixture - 32 to 50 to one mixtures, a plain bearing engine will not tolerate it."
Everybody is entitled to their own opinion and that is one of the neat things that makes up a forum. This is simply a run down of my opinion and an explanation of why I run the 30 non-detergent oil in my vintage Jac engines specifically. Therefore, there will be no need for me to debate any further on the subject in this thread.
The 2 cycle lubricants do not stay on the bearing surfaces long enough to provide full protection. If you take apart an engine run with the modern lubricants, you will find a dry crankcase - there will be no oil on the bearing surfaces. for roller and ball baerings, this is not an issue, because the lube just has to be there a split second to do its work. On a plain bearing, this dryness is lethal! Plain bearings need oil on both sides to provide non friction issued. direct contact between metals brings on shearing forces that will tear the bearings up. While a roller-ball bearinged engine will tolerate a leaner oil mixture - 32 to 50 to one mixtures, a plain bearing engine will not tolerate it."[/I]
NO, don't run 50:1. Mix it up 16:1 and you'll be fine.yeah thanks, i was thinking i would just pour in some 2 stroke that I use on my weedeater, 50:1 2 cycle, just to get her up and running.