Lawn Boy Duraforce Gas/Oil Mixture Recommendation

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Hey all -

I just picked up a good used LB with the 6.5hp Duraforce and will be using it for the first time this weekend. It's sat unused for a year, so when I started it before buying it, it had a small amount of white smoke coming out of the muffler. The previous owner stated that he used the cheapest 2-stroke oil he could find and followed LB's 32:1 mix ratio. He filled it up with what he had leftover because he didn't need it anymore, so when I got it home I dumped the tank and cleaned it and serviced the air filter. The plug still looks good and is an NGK of the correct part number.

I currently have cheap, basic 2-stroke oil that I've been using in my weed whip and edger at 40:1 ratios as called for by the manufacturers. Would I be safe in using the same 40:1 mix in the new to me LB? I'd like it to be as smoke free as possible without being under lubricated. I have a 1/2 quart container of this oil, then I'll need to purchase again and would be open to going with something better if it's needed.

Thanks for the forthcoming suggestions.
 
I've had good luck with the G-oil 2 cycle oil.

According to the manufacturer it is
Jaso FD, and api TC

The important thing is to use a name brand API TC rated oil at a minimum.

DO NOT USE anything rated TCW3
 
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Originally Posted By: Rand
DO NOT USE anything rated TCW3


Wait, the engine service manual that I found online had listed that if not using the LB branded oil that a NMMA licensed TC-W3 oil can be used. Has this been changed in the last 12 years (mine is a 2003 model)?

I haven't been able to find an oil that's just TC rated in any of the local stores.
 
I have a Lawn Boy 10552 with the same motor and have been using Echo oil 50:1 for the past several years without issue. Started doing this after talking to my dealer. To answer your question, you should be fine at 40:1. After you use up what you have, I would suggest either Echo or Stihl (at least that is what I'm doing because I have both on hand.)
 
I so wanted to find a good priced 10550 or 10552 because my last LB had the person pace and I loved it. This one is a 10324 and I got it with the bagger and mulch plug for $75 and couldn't say no. The deck is rust free and in good shape, but the aluminum deck would have been nice.
 
Originally Posted By: Alfred_B
I use 32:1 ratio with Quacker State 2 cycle oil in my LawnBoy.


Any noticeable smoke after it warms up a bit?
 
Having owned at least one of these at all times since they were launched, I have learned they don't care what you use. I have run everything from no-name TCW-3 to castor oil to Stihl Ultra at ratios from 16:1 to 50:1. I did teardowns occasionally, as I would buy a used one that had seals going bad, etc. The white/blue smoke at startup is normal for these. Mine didn't smoke much even at 16:1. Make sure the throttle cable is adjusted right. Because they go "WOT+" for the choke, you have to make sure that the transition from wide open/no choke to choke to be in the right spot. If it's not it will turn into a mosquito fogger.

Bottom line: As long as there is something resembling two stroke oil in the gas, you'll be fine. More of these are killed by straight gas or rotten gas than wear out.

Depending on how it runs, you might want to drill out the jets.
 
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Thank you for the relevant information. I think I'll use up the oil I have at 40:1 and see how that goes and make a decision when I need to buy more.

Just by ear, I think the throttle cable is real close as it runs and cuts without even a hint of bogging down. No surge as of yet, so I'll hold off on messing with the jetting.
 
I used to have a Lawn Boy Silver Series with the 6.5HP 2 cycle engine.

I used to use whatever 2 stroke oil I could find. Walmart sold the Supertech TC-W3 in quart bottles for about $2.50 a bottle. I used that with no problem.

I had to get rid of my old LB mower as the carburetor needed some parts but LB stopped making parts for 2 cycle engines after the EPA banned 2 cycle lawnmowers.

I ended up getting my Honda mower.
 
I bought a new Silver series Lawn Boy push mower the last model year they sold the two strokes.
I've been using Supertech outboard oil at 32:1 for years in it.

I've been using Champion EZ start plugs with good success @ lasting for 3 years.

My carb was replaced under warranty when the mower was about a year old.

The ignition coil died a few years ago and was replaced with a new one.
The shop that sold me the coil said to gap it using a business card.

I replaced the primer bulb once. I installed it crooked and I need to hit it 8 times instead of the normal 3. Oddly since installing it wrong, it always fires up on the first pull.
 
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Originally Posted By: threeputtpar
I think I'll use up the oil I have at 40:1


Please don't do this. The LawnBoy engine does not have connecting rod bearings. It has bushings. The reason for the 32 to 1 mixture has nothing to do with cylinder lube. It has to do with keeping that connecting rod big end bushing alive.

Also, the carb is jetted a touch lean. If it surges, the first solution is to install a slightly larger idle jet.

In my case, I used number drills and enlarged the idle and main jet by one drill size. It's a touch too rich. The Briggs idle jet is a better choice.

In addition, please go to the hardware store and install a fuel shut off valve. I shut my valve just before shutdown, preventing unnecessary flooding. Those carbs have cork floats and they sink. The muffler then fills with all your expensive 2 stroke fuel. Creating a large "fog" upon startup.
 
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Originally Posted By: Cujet
Originally Posted By: threeputtpar
I think I'll use up the oil I have at 40:1


Please don't do this. The LawnBoy engine does not have connecting rod bearings. It has bushings. The reason for the 32 to 1 mixture has nothing to do with cylinder lube. It has to do with keeping that connecting rod big end bushing alive.

Also, the carb is jetted a touch lean. If it surges, the first solution is to install a slightly larger idle jet.

In my case, I used number drills and enlarged the idle and main jet by one drill size. It's a touch too rich. The Briggs idle jet is a better choice.

In addition, please go to the hardware store and install a fuel shut off valve. I shut my valve just before shutdown, preventing unnecessary flooding. Those carbs have cork floats and they sink. The muffler then fills with all your expensive 2 stroke fuel. Creating a large "fog" upon startup.


Are big end bushings used in this particular engine? I've opened up a lot of 80's and earlier LB mowers and they all had needle bearings on the big end.
 
Originally Posted By: Alfred_B
I use 32:1 ratio with Quacker State 2 cycle oil in my LawnBoy.


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Cujet, thank you for the warning about the rod bushings. I think I'll start with the 32:1 mix and see how it goes.

The first thing I did was install a 90° fuel shut off valve. I think it may be most of the smoke issue as the needle seat likely needs to be replaced and I don't want to tackle that at this time. I plan of just running it out of fuel at the end of each cutting.
 
Originally Posted By: threeputtpar
Originally Posted By: Alfred_B
I use 32:1 ratio with Quacker State 2 cycle oil in my LawnBoy.


Any noticeable smoke after it warms up a bit?


Not after it warms up. At startup there is a plume of blue smoke but it goes away shortly.
 
Originally Posted By: boraticus
Are big end bushings used in this particular engine? I've opened up a lot of 80's and earlier LB mowers and they all had needle bearings on the big end.


The Duraforce engines used bushings, yes.
 
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