OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Honda Engines Honda GV400 - Oil Pooling in Manifold/ Carby

i`ll start at the beginning.i was in hospital & my lovely wife wanted to help out by doing the lawn for me,she comes in that night & tells me after filling with petrol that it wont start & petrol leaked everywhere.after getting home i find out that she has put about 2lt of petrol into the oil.

i drained all of the oil/petrol out of the motor including pulling the plug & turning over until no more oil was coming out,cleaned out the carby & putting fresh fuel & oil.motor starts up straight away,take it for a few laps around the yard & after a few minutes there is a huge plume of white smoke coming from the exhaust,shut it down & push it back into the shed.

upon taking the air cleaner off i see that the bottom of the inlet manifold has a large quantity of oil sitting in it.carby & manifold off again for a good clean out.

when i put it back together i leave the hose off the manifold that comes from the motor,i`m guessing this is some kind of crank case ventilation.mower starts up first go,but there is a constant spitting of oil out of the hose from the motor,very obvious how it could fill the manifold/carby in a matter of minutes.

so what am i up for here new set of rings, a complete rebuild ? or could i be lucky & it`s an easy fix ? motor has been a little smokey for a while but always very strong.

sorry for the long post but wanted to give as much detail as possible

cheers
jason

Jason if you filled motor with correct amount oil for your motor and its blowing smoke wait for a windy day and start it and let it run
it should clear it self out and run clean again after a while .
if may take 20minuts running
this happen a lot peple overfill oil, tip mower up side down ect ect
let it run awhile should come good

As freebird after such an overfill it takes a while to burn off all the excess oil in the exhaust and the exhaust must be at operating temperatures for this to happen.

You also said it has been smoking somewhat before hand too which is probably worn rings and cylinder. This can be the cause of the excess oil coming from the breather as there can be excess blow by. The best way to determine if this is the case without visual tear down inspection is the leak down test. There are several possible causes for excess crankcase pressure rings and cylinder wear are one but worn valve guides can cause this especially the exhaust as exhaust gases bypass the valve guide. Now a leak down test will not show worn valve guide(s) as it primarily tests the cylinder condition, head gasket and valves seating.

thank you for the replies. i did what you suggested to burn off the oil out of the exhaust.

i could be wrong but to me it seems like after running for a while enough oil is being pushed into the manifold that it is going through the carby,mixing with the petrol & burning off in the cylinder which is causing the huge amount of smoke

i did 1/2 an hours mowing without the breather hose connected to the carby & it ran fine,just had the constant spitting of oil out the hose.i was wondering if there could be any harm in using a catch can for this ?

re the mower blowing smoke before hand,it`s only ever been a tiny amount but i had always thought is was probably worn rings


cheers
jason