Just did my annual lawn mower oil change. Dumped out the old 30w oil and it poured out like water. Smelled like gas too. It's a Honda GVC160 engine. Otherwise it works perfect. Is it normal for these engines to dilute the oil?
Mower oil got thin
- Thread starter Dave1027
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The same happened to me once......but the oil I have put in previous oil change was cheap one too (No-brand name sae30) 
15w40 HDEO next time?
15w40 HDEO next time?
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You can do that too.
I use T4 10W-30 in mine. Next OC 15W-40.
I have the same Honda GVC 160 engine in mine but my mower is only 3 years old and has the auto choke. I use 5W30 synthetic and change annually with a new air filter.
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Use a higher HTHS oil. I prefer the ol' school SJ/SL oils...
A good synthetic motorcycle 10w40 or HDEO 5w40 are a good start for most small engines, or the higher HTHS 5w30's like Rotella T6 multivehicle 5w30 or Delvac Extreme 10w30.
Redline 5w30 is another if you want the 30 grade for colder climates and Redlines moly/hths goodness.
I'd also toss in the HPS/HMX oils from RoyalPurple.
Amsoil makes a small engine oil. Haven't seen VOA on it yet but expect it to be typically good from Amsoil. I'd guess that HPL, Driven, MPT... are some options, along with a couple VW and BMW oils.
And, its normal to look thin and smell like fuel. Without UOA data, looks really means little.
I don't worry about my small engines... generators, mowers, tractors, pumps.... I just change the oil(and filter if equipped) yearly and stick with ethanol free stabilized fuel. They pretty much run forever. If used excessively, like after losing power for a month because of a hurricane, my generators were getting changed every 200 hrs. Date time or run hours for the intervals, whichever comes 1st!
A good synthetic motorcycle 10w40 or HDEO 5w40 are a good start for most small engines, or the higher HTHS 5w30's like Rotella T6 multivehicle 5w30 or Delvac Extreme 10w30.
Redline 5w30 is another if you want the 30 grade for colder climates and Redlines moly/hths goodness.
I'd also toss in the HPS/HMX oils from RoyalPurple.
Amsoil makes a small engine oil. Haven't seen VOA on it yet but expect it to be typically good from Amsoil. I'd guess that HPL, Driven, MPT... are some options, along with a couple VW and BMW oils.
And, its normal to look thin and smell like fuel. Without UOA data, looks really means little.
I don't worry about my small engines... generators, mowers, tractors, pumps.... I just change the oil(and filter if equipped) yearly and stick with ethanol free stabilized fuel. They pretty much run forever. If used excessively, like after losing power for a month because of a hurricane, my generators were getting changed every 200 hrs. Date time or run hours for the intervals, whichever comes 1st!
No. I'll start doing that. Thanks
I would suggest you that you resolve that problem with a carburetor float/needle first (if it even exist...)
EDIT: its easy fix with Hondas&Chondas......because they have drain bolt and "cup" on bottom end of carburetor.....just close that valve....drain residual gas out.....unscrew that cup (watch that you dont loose its spring and needle) and clean needle seat with a Q-tip....
Then you can instal that float and needle with a spring back.....and test it if it seats properly ( push float in upper position.....and open gas valve....and observe if gasoline doesnt drips out...
If it doesnt seal.....you can pry slightly needle seat on a float to the point that it will seal eventualy
EDIT: its easy fix with Hondas&Chondas......because they have drain bolt and "cup" on bottom end of carburetor.....just close that valve....drain residual gas out.....unscrew that cup (watch that you dont loose its spring and needle) and clean needle seat with a Q-tip....
Then you can instal that float and needle with a spring back.....and test it if it seats properly ( push float in upper position.....and open gas valve....and observe if gasoline doesnt drips out...
If it doesnt seal.....you can pry slightly needle seat on a float to the point that it will seal eventualy
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This is a common problem with Honda carburetors. Unfortunately, there isn't a "fix" for it. The problem is that the seat is part of the carburetor body and is not serviceable. Pitting and wear from use cause it to leak and replacing the viton tipped needle valve doesn't help. The ONLY way to fix this problem is to replace the carburetor. They are VERY cheap on eBay.
Shouldn't have to if the carb is in working order.
Before assuming the worst, check your oil level before you use it next. A leaking needle and seat can fill the crack case with gas and will raise your oil level. If it's all good, then don't worry about it. My old mower with a Briggs had a leaking needle and seat and it filled the crank case where the oil level was ABOVE the full mark on the dipstick and spilled gas out of the intake on the floor. Had to replace the carb to finally fix it.
As far as oil smelling like gas, it only takes a tiny amount of gas to notice the smell. All of my engines oil have a faint hint of gas. Just smelling it isn't a good indicator of the condition of the oil IMO.
As far as oil smelling like gas, it only takes a tiny amount of gas to notice the smell. All of my engines oil have a faint hint of gas. Just smelling it isn't a good indicator of the condition of the oil IMO.
I have the GVC160 on my troybilt lawn mower too. Last year, I had the same issue where fuel was weeping and flooding my air box and into the intake manifolds to the combustion chamber but on my atv. It was leaking through two places which was the spring loaded petcock and through the needle and seat of the carb. The e10 fuel does destroy aluminum as evidenced with the pitting and goop from the water attraction sitting for years.
I solved this with bar’s keeper friend or Ajax and toothpaste to make an abrasive goop. I coated a q-tip and worked my way into the seat with a drill many times until it seemed ”good” enough. Then I took the shutoff needle and used some bodywork sand paper that was about 2500 grit and polished the ribs on the needle. You can tell it did something because when you drop the needle in the seat, it would sometimes hang up. Now no matter what angle, the needle would freely travel through the bore where the taper would seal well against the seat.
That was the only way I got the carb to stop leaking as I did not want to replace the carb just yet.
Also, when I took the carb off my mower for other reasons, the intake gasket tore easily as it was quite old so you may need to prepare accordingly.
I solved this with bar’s keeper friend or Ajax and toothpaste to make an abrasive goop. I coated a q-tip and worked my way into the seat with a drill many times until it seemed ”good” enough. Then I took the shutoff needle and used some bodywork sand paper that was about 2500 grit and polished the ribs on the needle. You can tell it did something because when you drop the needle in the seat, it would sometimes hang up. Now no matter what angle, the needle would freely travel through the bore where the taper would seal well against the seat.
That was the only way I got the carb to stop leaking as I did not want to replace the carb just yet.
Also, when I took the carb off my mower for other reasons, the intake gasket tore easily as it was quite old so you may need to prepare accordingly.
RTV silicone will fix that.....
Bought a new gasket on Amazon for $4.55 so i would rather go that route.
That's about what a sheet of gasket mat'l cost. I have about 3/4 of a sheet left after 20 yrs. Main reason is that I can finish the job without a 'go back'
This^
Also turn the fuel valve off when not using the mower, it's quick insurance. It only takes one little particle of something to get stuck on the needle valve and fill your crankcase with fuel. Oil smelling strongly of fuel and being very thin isn't normal.
In theory, but all it takes is one little grain of sand or a particle of something to get lodged in the needle valve and keep it from sealing. I've even seen part of the rubber fuel line get eaten away by the fuel and lodge itself into the valve, and it filled the entire engine full of fuel on a Briggs V-Twin. It was hydro-locked solid, all from an aging fuel line, and the fuel not being turned off.
