Ok so my RV/MH had a no start condition. I would turn the key and the starter wouldn't turn. After replacing bad cables, starter, solenoid and recharging the batteries I would only get a click. Prior to this the RV was smoking white like crazy. I thought I had a blown head gasket but couldn't further diagnose becasue of the no start.

A few days later I noticed a major leak from the dip stick. Never leaked before. Odd thing was, it was thin black liquid. Smelled like fuel. I took a piece of cardboard and dipped it in the leaked fluid and lit up. I drained the pan and it came out like water, super thin and black, smelled like fuel. About 2 gallons worth on a cold engine.

Somehow fuel was getting all the way into the pan in huge amounts. I remembered reading something about possible hydrolocked but didn't think it was possible if it was fuel in there, usually happens with water from what I recalled.

I pulled the plugs and two were soaking wet. When I pulled the plugs they were fouled so I replaced. Prior to replacing with all the plugs pulled I went ahead tried to turn the engine. Turned over like crazy and spat out remaining fluids in the cylinders (I had bypassed the fuel pump). I concluded fuel was getting dumped into the cylinders and not burning and it got so bad that the pistons couldn't compress it for the engine to turn.

Determined my fuel pressure regulator was bad. Replaced (five minute job with the right tool) and BOOM fired up right up once it was pressurized. Let it idle, little bit of white smoke at idle nothing major. Let it sit three idling and did a visual for leaks or anything else nothing. Took it around the block and.....

Smoking like crazy. Prior to the no start I remember "condensation" coming out of the pipe but now I know it was fuel. It isn't spitting fuel out the pipe now but still smokes.

Could it still have a bunch of fuel mixed oil in the engine that it needs to run out? Only idled for about 10 minutes before the run around the block. Not even up to operating temp. Wondering if I should just take the smoke machine out and run it on the freeway to make sure.

 

I'd change the oil again to be sure

 

Yeah I'd do that ASAP and maybe once again about 500-1,000 miles later just to be sure you're running all oil, no fuel.

I'm thinking you're VERY lucky to not bent a rod or something equally severe with that degree of hydro-locking.

 

I went ahead and drained a little oil from the pan it appeared to be back to normal. Ran it to the gas station and no more smoking. I'll be draining the oil after a few hundred miles.

 

Would help if you posted the year and engine this RV has.........

As an added pre-caution, and the engine still blowing out white smoke, you could have a bad (open) injector that's flooding the engine.

A bad Pressure Regulator is always a source for fuel flooding, but if it's seams like it's still flooding with raw gas, then replacing the injectors with new re-man *cleaned-tested* injectors is a good permanent fix.

If you drained out oil/fuel mix, you also washed (flushed) out the engine really good, and I wouldn't run the engine too long with out draining the oil again real soon, like in under 200 miles, or a couple of hours, because there is still some fuel residue in the engine crank case and journals and bearings, breaking down the new oil.

I know oil is not real cheap today, but a lot cheaper than a blown engine.

 

I would fill and run and drain the oil a few times. Use the cheapest oil you can but flushing fuel from the lubrication system is a must. Do a filter change. Finish up with the recommended oil and a new filter. Very lucky to not have damaged a bearing or lifter.
jim