Stump grinder engine honda gx390

[ukminch]

Went out today to a grinding job with my little grinder. I'd lent to to someone I know who had had it stored outside (water relevant?)

 

Came to start it starter cord seized solid, quickly released it was a compression lock, somehow? Took spark plug out pulled it over cleaned plug, replaced, and repeated until it eventually started. Ran for about 10mins then cutout with a load of white smoke everywhere.

 

I assumed some water had got in hot piston, cold water cracked piston, pulled head off this eve and found it looks ok with shiny bore still. Attached a couple of piccies of the milky oil (Oil in sump is this colour to)

 

Have I just got water in there, oil change and all will be good, or do I need to pull it apart further and check the piston rings, or any other good ideas

 

Cheers in advance

R

[Breezeblock]

you have got nothing to lose drain off oil fill with fresh run it then drain it off again and see how it goes also if it cuts out disconnect the low oil shut off

[Rich2484]

yep swap the oil, run and change again.

 

seems like water in oil. not sure how unless it got really soaked and got into the breather.

 

also check the valves over aswell. if they have got rust on they can destroy the guides or seats.

 

hondas are relatively bomb proof, the bore looks clean.

[Stubby]

You probably got a soggy wet air filter ......

[ukminch]

Nope air filter is bone dry, bore is indeed how I'd expect it to be, valves seem fine, time for an oil change, what oil is it in the GX390? Only place I can see that water could have got in is through the exhaust, must have just been at an unlucky angle.

 

Im presuming if I'd knackered a piston ring the bore would be scored?

 

Cheers guys I'll let you know how I get on, probably be the weekend though now :-(

 

R

[GardenKit]

To have water on top the piston is one thing, but to have oil and water is another

 

For this to happen the engine must have been on its side, or partly submerged.

 

Whatever the cause, drain it out , refill with a 10w 30 or similar oil, see if it will start (bearing in mind the carb and fuel tank may also be contaminated)

 

If it starts, run it for about 5 minutes and change the oil again. Repeat this until the oil stays clear.

[ukminch]

Yer I'm quite surprised, we have had a lot of rain I guess, I trust the guy that's had it, but equally it's not like I know exactly where it's been or what it's done......

[redmoosefaction]

Went to Honda the other day and they said you need to put in 10-30 with some letters after it, they said this was very specific for GX390 engines, it came in at just under a tenor. You need 1.1L

[2stroke-ady]

It does look like water in the oil but it doesn't make sense.

 

Has petrol leaked past the float needle in the carb and filled the sump with petrol? That might explain it.

[predator]

Thats deffo water in oil jet washed off maybe ?? and as its only a small engine would only need a small amount of water to emulsify the oil ie frothy oil syndrome if its hydraulic,ed just check the piston sits at the top i,e bent a con rod hope not and all works out ok for you. also in the pictures does the breather return from crank case to air filter if so thats poss how its got onto/into the bore etc