Simplicity Smoke Screen

8N'r--WI · May 12, 2014

I picked up a Simplicity rider a month back...starts on first/second rotation, no smoke, replaced a bearing on the cutting deck...put new plug, gas and oil filters, etc.

Yesterday, I went to actually cut some grass with it and when the engine got under load, a THICK cloud of blue smoke came out the exhaust pipe until I stopped the tractor. Checked oil, it was full. Ran it back up to the house and let it run with the mower engaged and without. No smoke.

Took it out again and the same thing happened. Rings shot? Valves shot? Only smokes, and smokes real bad, when the engine gets under load. It looks like I am fogging mosquitos. 15 HP Briggs with hydro trans

Thanks, Tim

joe csuti · May 12, 2014

If eng has a tube/hose from breather valve to air filter assembly,remove air filter & check for oil in filter houseing & filter element if dry type or excess oil in foam filter,oil in filter houseing & excess oil in dry/foam filter can be caused by several things-over full oil level,sticking,leaking or stuck breather valve or excessive blow by into crankcase due to worn cyl/rings & worn valve guides.

8N'r--WI · May 12, 2014

Thanks Joe---"possible excessive blow by into crankcase due to worn cyl/rings & worn valve guides."

I am hoping for an inexpensive fix......but if rings and valve guides are worn out, wouldn"t there be smoking even when the engine is at idle?

Thanks, Tim

joe csuti · May 12, 2014

Depends on the amount of wear on cyl/rings or valve guides,with eng at idle & no load on eng you may be getting little/no blow by,when you put a load on eng temp of eng increases & internal clearance on any worn parts will also increase,another possible cause of problem may be mech drag on eng caused by worn parts in drive train,transaxle or mower deck overloading eng.

The first thing I would do is explore the possibility that you have a sticky,dirty or bad crankcase breather valve & fix may be as simple as cleaning or replaceing breather,if you still have problem after cleaning/replaceing breather then consider doing a leakdown test on eng,this will help you determine if you have blowby past rings or leaking valves,however it will not tell you if valve guides worn,you have to pull head(s)remove valves & measure id of guides to determine if guides worn.

504 · May 12, 2014

I have a White with a B/S on it doing the same thing. I worked on this mower and it ran fine so I bought it from the owner(he had bought five mower from a dealer)Took it home and you can not see the front tires of the mower for the smoke. After mowing the yard it quit smoking, I checked the oil and it was dry!

jeffcat · May 12, 2014

I will second what you have Joe. First thing i though was too much oil in the crank case. Next is, if the breather valve is stuck and the crankcase will go positive pressure. Crudy air filters will cause the engine to suck really hard and you again get smoke.
Now another thought. If he has a carb float problem and it pulls a slug of gas you will also get a blue cloud. The engine will most likely almost die. If it just keeps runnig making smoke then oil trouble sounds like what he has. Could it be a blocked oil drain galley under the valve cover??? The valve area Will just fill way up and again you can get oil smoke. Saw this one time long ago on a very early OHV vertical engine. Idiot NEVER changed oil just top off. TONS of crud all over the place. Check under the valve cover. Only takes a few minutes to see if the oil can drain out. While you are in there you can check the vales. 4 on the intake and 6 on exaust. I run 5-30wt sythetic blend in all of my small engines. I did the valves on my Troy pony tractor after 5 seasons and the engine was SPOTLESS under the valve cover. Blew me away.

IH2444 · May 13, 2014

Jeffcat,
I use synthetic in all my small engines.
Teh Kohler 301 on my old Gravely started shutting down after it got warm. 1/2 hour later it would run for maybe 15 minutes.
Investigation showed the intake valve to be sticking open. Changed to synthetic oil in it and the problem went away.
I still have the new valves and guides in a box 5 years later.
Might get around to sticking them in someday.

Tom Arnold · May 13, 2014

While I agree that changing to synthetic oil might help with the
sticking valve issue, it will do nothing to solve worn out rings
and valve guides.

I agree 100 percent with Joe Csuti. Investigate the crankcase
breather system first but ALSO.... perform the Leak Down Test.

What I find interesting is that you do not notice even a slight
tinge of blue in the exhaust smoke when the engine is not
performing any work but when pushed hard, you are suddenly
engulfed in a fog. LOL

I am looking forward to reading about the results of the leak
down test because no matter what, I think that you have an
engine in need of a complete rebuild.

jeffcat · May 13, 2014

You bet!! How in the world did we get along with out that stuff? As I said; I have seen SO many engines with crud out the ^&*(* but the synthtic engines are clean as a whistle! Just mowed across the road at the cemetery with my big used Husqavarna that I rebuilt. Brggs twin 21hp and a 46" deck. Use the 5-30wt in it. What a SWEEEEET rig. Hope this guy gets back to us with what he found.

Tom Arnold · May 13, 2014

The only reason that synthetic oil exists is because the Allied's cut off Germany's supply line to crude oil and their chemists came up with a synthetic substitute to keep all the engines in the German Army running.

Synthetic has certain values but the fact is.... all oils get dirty and the only way to get the dirt out is by using filtration and timely oil and filter changes. That is what keeps engines clean inside, not the use of synthetic over dino oil.

And it is not the oil that cleans the inside of engines, it is the detergent that is added to the oil. It keeps the dirt in suspension so that the filter can remove it. Detergent is a component of synthetic and dino based oils unless stated otherwise on the container.

joe csuti · May 13, 2014

I also RECOMMEND you get a service/repair manual for your make/mod eng,most/all breather valves have drain hole(s)in body without knowing history of eng & make/mod of eng previous owner may have had breather out/apart and on many of the older briggs & tecumseh L head(flathead) eng the breather will fit either way,right side up/upside down & the drain hole(s)in breather body are faceing the wrong way,if faceing the wrong way breather will fill with oil then blow oil into carb rather than draining back into crankcase,in addition if eng an L head briggs depending carb used on eng breather tube/hose connected to a nipple on side of carb body,in which case you won't find oil in air filter houseing/filter element.Disconnect breather tube/hose from carb,see if smoke stops & watch for oil comeing out of pipe/hose,then take it from there.

T.R.K. · May 13, 2014

I am thinking that engine would be the single cylinder Briggs with overhead valves. It probably has a blown head gasket. They usually blow near the pushrods.

Briggs has recently raised the torque spec. on those head bolts, but I can"t remember what it is.

8N'r--WI · May 14, 2014

Joe---I was able to find/print the manual and parts manual for the engine off the net....I will hope for the best, and try disconnecting the breather tube from the carb first and hope that stops the smoke.

Then, I will check out the breather valve to see if it is installed correctly....

FYI---before I even got this mower home, I had a simplicity dealer look it over....I had changed the plug, gas filter, oil filter, oil before having him put the bearing in the mower unit....he said "everything seems to be working great"....but that was before I put it under load.

Thanks,

Tim

8N'r--WI · May 14, 2014

Thanks to All for your info and input...when I get home this weekend, I will try a few of the "easy/inexpensive" fixes and hope for the best....no bad rings or valves.

I will get back and let you all know what happens.

I do most of my mowing with a 5" brush hog, and picked this simplicity up primarily for hauling a lawn cart filled with beekeeping equipment for my small bee operation...and to have something my wife can do the "hard to get to with a tractor" spots that need mowing..

Thanks, Tim

TRACTORNUTJD · Jun 27, 2014

Blown head gasket, stay away from synthetic oil , straight 30wt change every 50 hours. Head gaskets are common problems on these engines

Bret4207 · Jun 28, 2014

(quoted from post at 12:41:29 05/14/14) Joe---I was able to find/print the manual and parts manual for the engine off the net....I will hope for the best, and try disconnecting the breather tube from the carb first and hope that stops the smoke.

Then, I will check out the breather valve to see if it is installed correctly....

FYI---before I even got this mower home,[b:f163ac2d7e] I had a simplicity dealer look it over....I had changed the plug, gas filter, oil filter, oil before having him put the bearing in the mower unit....he said "everything seems to be working great"....but that was before I put it under load.[/b:f163ac2d7e]

Thanks,

Tim

Yeah, that's a classic line. If the dealer, or any wrench, doesn't try something under load and warmed up then how does he know it's "okay"? Charge a customer for work and you didn't really test it and it's not fixed right...you aren't going to be in business for long around here.

Simplicity Smoke Screen

8N'r--WI

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joe csuti

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8N'r--WI

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joe csuti

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504

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jeffcat

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IH2444

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Tom Arnold

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jeffcat

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Tom Arnold

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