Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: 2 stroke oil question
Posted by Turpin on 07/22/13 - 8:24 PM
#1
I have switch 2 stroke oils going from penzoil to Evinrude.
I use 50:1 mix for my 1992 Evinrude 50hp.
I have noticed the motor smokes less at start up but the remarkable thing is, my previous WTO was about 5400k +- 100 now it is constantly 5800k.
So the question, is it the fact this oil is cleaner and more efficient burning causing the engine to run faster?
I'm assume this is a DUH, question so I would like to know has anyone else ever notice such a drastic difference?
It was almost equivalent to changing props.
Posted by Tom Hemphill on 07/23/13 - 4:03 AM
#2
Did you change from traditional oil to synthetic?
Posted by dauntless-n-miami on 07/23/13 - 8:33 AM
#3
Hello Turpin, that's a respectable rpm jump just by swapping 2 stroke oil brands.
Just for the sake of your outboard check the condition of your spark plugs for a possible "lean situation". If they have been in for a while it may be hard to tell due to the oil/carbon build-up. Maybe test with a fresh set of plugs on your next outing while using this new brand of 2 stroke oil.
Some 2 stroke oil blends (especially synthetics) can do strange things to an older motor so be cautious.
2 stroke's have a tendency to "rev-up" if they develop a lean condition and will run hotter as well.
Just recalling past experiences with 2 stroke hobbies.
Posted by Turpin on 07/23/13 - 9:09 AM
#4
Yes, it is a synthetic, I'm typically also against running synthetic in older engines also but hadn't given it much thought with 2 stoke oil on a boat. I'm cautiously optimistic. I will check plugs.
Posted by whalerman on 07/23/13 - 9:40 AM
#5
Which Evinrude oil did you switch to.
Posted by Turpin on 07/23/13 - 1:52 PM
#6
Evinrude Super Premium synthetic (i can't help but laugh at the name)Actually it wasn't my 1st choice, but I was in a bind and my dad had a unopened gallon to lend. I was going to go with the (I think) XD- line.
Posted by dauntless-n-miami on 07/23/13 - 2:22 PM
#7
Synthetics oils (2 stroke or motor oil) are excellent products. The issue with them and older motors that have been accustomed to "dino" type oils is, their incredible ability to clean or loosen carbon deposites that have accumulated throughout the intake and exhaust areas of some motors.
This also includes older 4 stroke vehicles and motor oil. The synthetic blend you are using might be wiping off or dissolving the old oil film that the piston rings and cylinder walls have grown fond of thanks to the older technology 2 stroke oils you and a previous owner may have used.
For this reason I thought of a "Lean Condition" for the jump in rev's.
Angel M.
Posted by Derwd24 on 07/23/13 - 2:43 PM
#8
What component of the synthetic oil is responsible for the cleaning aspect?
Posted by Turpin on 07/23/13 - 3:48 PM
#10
Part # 767003
Posted by whalerman on 07/23/13 - 4:54 PM
#11
For an engine of that vintage I would use the XD50 oil. Less expensive than the XD100 which your engine would not benefit from as the hours of operation and wear that has already taken place on the crank and rod bearings. IMO.
Posted by Joe Kriz on 07/23/13 - 5:08 PM
#12
Turpin,
That doesn't tell me much nor tell me where to go.
I gave you the Evinrude link and nothing is there except XD Oil.
I agree with Thom.
XD-50 is all you need if you want a little better then the XD-30
Posted by Turpin on 07/23/13 - 7:57 PM
#14
I appreciate all Inputs and apologize for the lack of a proper link but I'm doing this inquiry from a phone (a proper pc is not available at the moment) and everything wants to give mobile-phone hyper links.
I was mostly just curious was this rpm increase customary with the use of better more efficient oils.
Posted by CES on 07/24/13 - 6:11 AM
#15
Motors always seem to run their best.....just before they blow up.
Just sayin'......
Posted by dauntless-n-miami on 07/24/13 - 7:13 AM
#16
In replying to Derwd24,
I am more familiar with automotive pure synthetics but I would figure 2 stroke synthetics if 100% would share similar qualities. Unlike conventional "Dino" oils, engineered synthetics benefit from higher resistance to thermal breakdown, inproved lubricity and superior detergent additives for the dispersal of contaminents. Thus the reason engines on synthetics have extended oil change service intervals.
Synthetics also have a bit different viscosity rating than conventional oils do which will also cause issues in older motors.
Motors that have been designed to run on "Dino" oils will accumulate over time carbon deposites, some slug and thicker oil films on cylinder sleeves, piston rings, crank bearing and the likes. The bulk of the recipocating parts.
Synthetics will have a tendency (because of their design) to breakdown these accumulations within a motor and in some instances a motor with high op. mileage or hours that ran well on coventional oil now begins to smoke a bit and "burn" oil as some say. In other instances they exhibit lower compression test results because the thicker oil film that helped the piston rings seal to the cylinder wall is no longer there.
It's not that the motor has gone bad but, the synthetics have begun to (let's say) de-contaminate the internals.
I would suspect that 2 stroke pure synthetic oils would share very similar properties as their automotive brother does. Turpin mentioned using a pure synthetic by chance if I recall.
Just my thoughts on the topic...
Angel M.
Edited by dauntless-n-miami on 07/24/13 - 7:23 AM
Posted by seahorse on 07/24/13 - 7:24 AM
#17
That Johnson-Evinrude oil sold at WalMart and other outlets is a different oil than the XD series that an authorized dealer sells. This is a less expensive oil that is marketed for mass merchandisers, and is not the same nor does it even smell the same as the dealer stocked lubricants.
Posted by whalerman on 07/24/13 - 7:42 AM
#18
To really see if there is a difference in rpm you will have to run the boat again to see if it were an anomaly in the readings. Sorta like doing speed trails to cancel out wind and current. But it is possible to have an rpm increase. Seahorse is very correct about the walmart oil and you should stay away from it, IMO.
Posted by Can_38 on 07/24/13 - 8:21 AM
#19
Turpin wrote:
I appreciate all Inputs and apologize for the lack of a proper link but I'm doing this inquiry from a phone (a proper pc is not available at the moment) and everything wants to give mobile-phone hyper links.
I was mostly just curious was this rpm increase customary with the use of better more efficient oils.
My experience here is if you don't provide all information and type it exactly to a specific format you will get more questions in return than helpful answers.... just my $0.02.
Posted by Turpin on 07/25/13 - 9:17 AM
#20
Well I did testing this morning as I still had old mix in my 3.5gal "o'crap" reserve tank tank. It appears my loads must have been different, the original 400rpm was as most suspected in accurate. The actual difference is negligible but doing my testing I did manage to consistently hit a hair raising 43mph and once 44mph.
So I apologize and thank everyone for their input.