flooded engine cylinders

[upallnight]

Originally Posted by bcredliner

If an engine was like a gas tank there would still be compression in those cylinders with closed valves the next day. Also, it doesn't take much of a flooded condition to wash the oil film off the cylinder walls to the point they don't seal. Cylinders are not airtight.

Air is always compressible, a liquid is not.

If there is enough gas to wash down the cylinders, the cylinders and plugs are wet and like my dad told me, you are not going to start an engine with wet plugs.

Here's a thread on a guy who couldn't believe his engine was flooded. He tried for several days to get the engine started. Finally gave up and had the car towed to a shop. When the mechanic worked on the car he found the plugs dripping wet. The mechanic dried the plugs and ventilated the cylinders expelling any gas still remaining in the cylinders. Put the plugs back in and the engine started right up.

https://www.bimmerforums.com/forum/s...0#post25719750

[bcredliner]

Certainly if plugs get soaked and you don't wait long enough for them to dry any new attempt to start the engine will re-soak the plugs. It is also true that removing the plugs is one way to correct the problem without the wait. That is, unless something else is causing the flooding, not cold weather and/or slow cranking.

My point remains the same, overnight the plugs should dry out and the flooding condition gone. That doesn't mean the engine will start if something else is causing the flooding. There is nothing in that thread indicating how long between the last start attempt and when the mechanic pulled the plugs. My bet is the first thing the mechanic did was try to start it, before he went through a systematic troubleshooting list.

Based on the prior missing condition, something was failing, likely causing the flooding. My suggestion for that thread would have been to start with the simple troubleshooting stuff, air restriction, fuel pressure and spark. If I didn't find anything I would pull a plug to read if air/fuel mixture is reasonable. If not, I would check another plug. If also wet, to save I might pull all plugs, clean them and put them back in an hour or so. When it is back together I would not assume all is well. For first start attempt I would spray starting fluid. Depending on how they looked it would indicate the next step.

My point with washed down cylinders had nothing to do with starting or not. It was that when the rings aren't sealing more air can enter or exit all cylinders. Even when that is not the case a cylinder is not air tight and will allow evaporation.

I think sticking to the simple troubleshooting steps here is always the best approach since members have varying experience, tools and testing equipment. Unfortunately, many members don't have a code reader which is always my first troubleshooting step.

[talljames]

Heh guys, I seem to be having the same issue. So I left it overnight. Today I went out and tried the above procedure with the foot to the floor and it started up first time to a very high rev. Then when I took my foot off the pedal the revs came down, it stumbled and died. I tried once more for a short time but all I got was cranking. Did it really take 6 times to start? What if it is not fuel but oil.

cheers

[bcredliner]

Did you have any other symptoms prior to the no start?

[talljames]

No, it just happened. The solution was a faulty fuel pump that just died on me when these symptoms began. All good now.

[Zulu95]

My first BMW had auto chokes on the twin carbs setup and despite a number of dealership attempts, the auto chokes would not work properly and flooded the engine numerous times. Once I had to overnight at a friend's house so I could recharge the battery and remove the plugs the next morning to blow out the cylinders and dry the plugs.
Ah, good times, good times......