Fuel in oil now

[randy becraft]

Hi everyone, Think I finally got my carb right today and as luck would have it, something else happens. Was trying to adjust air mix for a good idle after re-building this mercarb(had lots of folk's guiding me along lol) when oil/fuel mix just started blowing up and out of pvc hole.Engine was running good when this started..Shut it off and wiped engine off as best I could. Then re-started it thinking it was flooded by now, but it started good and idled good.But oil/fuel was spitting out of dip stick tube now.Shut it off again, and found oil level to be way high.Figuring it's the fuel pump gone bad now, but the gasket area and lever wasn't soaked with fuel as I thought it would be.May had dried by the time I got it completely off to check..And no fuel was in the clear tube going to carb.It felt stopped up at pump end when I tried blowing or sucking through tube.Anything else cause this besides bad pump? Thanks all 93 3.0LX 2 barrel mercarb...

 

[tinkerguy70]

Re: Fuel in oil now

I'd say you're on the right track with the fuel pump.
Unless the carb is dumping a bunch of fuel into the engine, that's about the only place it can come from. You stated that the engine was running smoothly and well, so that pretty much eliminates the carburetor. If it was dumping that kind of fuel to get past the rings and fill the crankcase, it wouldn't run well, if at all.

 

[Don S]

Re: Fuel in oil now

The fuel pump is the ONLY place that can dump that much fuel into the crankcase while the engine is running. If it was coming from the carb the engine would flood and die and the gas would be in the intake manifold and the cylinders, not the crankcase.

Replace your fuel pump before you start the engine again. You don't want to find out what happens when the gas in the oil pan ignites and explodes.

 

[ENSIGN]

Re: Fuel in oil now

Also change the oil and filter.

 

[randy becraft]

Re: Fuel in oil now

Will do on oil change and new pump.Is it likely though that while idleing for just a few minutes at most, the pressure could build up inside engine enough to blow fuel and oil out at the rate this was blowing? Want to think the pumps the cause, but am woundering if anything else could go bad and cause this much pressure. Took the pump apart as far as I could figure out and looked at the large diaphragm.Didn't look cracked or rotted. I know theres more to remove to see the other diaphragm, but couldn't figure out how to get pin out of pump arm to remove. Theres no plug;s to remove to push pin out. Also I haven't found this flange number on any web sites(070117); and wounder if it was even the correct pump for this 93 model 3.0LX with engine serial#0f067528.Checked compression (cold) and all cylinder's pumped up to 150psi.At the time of compression test, engine was flooding (carb problem's) and wouldn't start without cleaning all plugs and spinning engine over a lot to expel excess fuel from cylinder's. So i'm not even sure that test was correct.This pump has both inlet and outlet fitting's on the same side. Haven't seen any on line like this.Thats why i'm woundering if it's the right one...Thanks for all you'r help guy'

 

[MolsonCanadian]

Re: Fuel in oil now

Could it be fuel in the oil from BEFORE the carb rebuild when it was flooding?

 

[Bondo]

Re: Fuel in oil now

Is it likely though that while idleing for just a few minutes at most, the pressure could build up inside engine enough to blow fuel and oil out at the rate this was blowing?

Ayuh,... If the oil level is High enough, the crankshaft Beats it into a froth, 'n does all sortsa crazy things....

 

[randy becraft]

Re: Fuel in oil now

Got a point Bond-o, Level was two inches over full once I noticed this happening.Had checked it a day or so earlier and it was alittle low,so didn't think to check it again. Had a bad valve cover leak that I found once I got it running so I fixed that..Had lost maybe 1/2 qt.Float was bad and three day's of messing with that before replacing the float could have dumped it in...Kept having to pull plug's and blow fuel out to get it to start.Carb was dripping fuel into intake ,so I re-built it without a new float...Waste of time without new float...Lesson learned...lol Thanks