# Too much blow by on RYOBI 6500 w Generator



## Sparky350ci (Mar 6, 2021)

First let me start off by saying I know very little about engines.

I bought this generator second hand a few months ago and have ran it about 15 mins unloaded ever week to keep it from gumming up. I never noticed any previous issues. 

During the Texas winter storm my generator was leaking oil via the air filter box. Load was roughly 4000W. After some investigating I found it was due to oil blow by. I belive it was a severe amount. Maybe a half a quart over 3 days time. Other than that it ran fine and never gave me any power issues.
Today I removed the original hose that connects the OHV cover to the air filter box. I bought a longer hose and connected it from th OHV cover to an empty water bottle ( with some holes drilled at the top for gas to escape.) It collected maybe a cup of oil in 3 hrs time.

I removed the OHV cover to inspect the and there was a lot of oil under the cover, about a cup or more( from videos I have seen of cover removal my situation did not look normal)
I did fill with oil before storm as manufacture instructs. The floor may not have been 100 percent level but I doubt it was so unlevel as to affect over filling.

Any ideas? Should I remove all the oil under the cover around the valves?


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## iowagold (Jan 22, 2020)

there should be a crank case vent valve, it could be stuck or broken.
most of them are a plastic reed or rubber flapper style.

make sure you are not over filled with oil in the crank case!

an oil change and fill with the correct amount works.
make sure you do not have a over fuel carb issue that is thinning out the oil.

is the drain to crank case working right for the valve cover area?
check for gasket material or rtv corking up the valve cover head area to crankcase drain


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## Sparky350ci (Mar 6, 2021)

Thanks for the reply iowagold.

The crank case vent valve seems to be operating as it should. ( when I blow on the tube it does not let air in. If I suck it does let air pass)

I'm definitely not overfilled with oil. The dip stick is actually showing low oil.

I'm not sure how I could check if I had an over fuel carb issue.

I'll check for a drain to chank case maybe this is the problem... I was not aware of a drain here. The is alot of oil in the valve cover area. When I take off the cover I need a pan to catch it from falling on the floor. I removed the oil from this area yesterday and ran the gen for 1 hour and did not get any excess blow by oil.


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## iowagold (Jan 22, 2020)

Sparky350ci said:


> Thanks for the reply iowagold.
> 
> The crank case vent valve seems to be operating as it should. ( when I blow on the tube it does not let air in. If I suck it does let air pass)
> 
> ...


what does the spark plug tip look like?
is it black?

yea make sure the head drain back passage is open.
sounds like it is plugged if you had a lot of oil when you removed the valve cover.
*is this your gen? or is it an older version?*
send over the exact model number and i can look up the parts blow up for you.
the modern 420 engine is a honda gx390 clone.
easy to work on!


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## Sparky350ci (Mar 6, 2021)

That's the gen, my model number is RY906500S (099930624).

If I can find the time today, I'll take a look at the spark plug and try and find the head drain back passage.


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## iowagold (Jan 22, 2020)

wow!
yea something is plugged!
it may have too much sealer somewhere...
or it might be not drilled??
did it just start this
or has it been and issue from brand new?
thinking a bad casting maybe!


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