Author Topic: That day, when Goldie scared the living daylights out of me  (Read 143 times)

ptashek

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That day, when Goldie scared the living daylights out of me
« on: 14 September 2020, 08:39 AM »
Had a proper scare yesterday... I've taken Goldie out for a drive, and she felt a bit rough from the get go. Unstable idle, lot's of vibration, loss of power, she smelt rich and drove like a bag of potatoes. All kinds of scenarios went through my head, from stale fuel (most likely, as hasn't been out much this year) to vacuum leaks, to some serious engine or K-jet trouble. But as I had no time to go looking, I kept on driving like this for another 60km before having a chance to pop the hood and taking a look around.

Turned out, the ignition cable on cylinder #2 somehow fell off of the spark plug, and I was driving on 7 cylinders all this time!
Secured it back in, fired her up and the sweet harmony and oomph returned :)

But on second thought, I might have been incredibly lucky the engine didn't hydro-lock as the injector would still have been dumping fuel into the cylinder all this time? Or am I getting this wrong, and all that atomised, unburned fuel would have been easily cleared out the cylinder every cycle, and that was all the fuel stink out the tail pipe?
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revilla

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Re: That day, when Goldie scared the living daylights out of me
« Reply #1 on: 14 September 2020, 09:38 AM »
Hi Lucas,

The unburned fuel has only 2 ways out. Through the valves to the exhaust as you suggested or through the rings down by gravity to the oil channels/pan.
It happened to me once trying to start a VERY rich engine (high mileage probably worn rings, not your case I’m confident).  When I checked the oil stick it was stinking fuel all over. An oil change was mandatory then.  But that was when trying to start the engine repeatedly. Your case was different as the engine was running for some kms. But check your oil stick anyway as a preventive measure.
Good luck.
Robert

« Last Edit: 14 September 2020, 12:19 PM by revilla »
Robert
W116 1977 280SEL & 1979 280SE

raueda1

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Re: That day, when Goldie scared the living daylights out of me
« Reply #2 on: 14 September 2020, 02:39 PM »
Had a proper scare yesterday... I've taken Goldie out for a drive, and she felt a bit rough from the get go. Unstable idle, lot's of vibration, loss of power, she smelt rich and drove like a bag of potatoes. All kinds of scenarios went through my head, from stale fuel (most likely, as hasn't been out much this year) to vacuum leaks, to some serious engine or K-jet trouble. But as I had no time to go looking, I kept on driving like this for another 60km before having a chance to pop the hood and taking a look around.

Turned out, the ignition cable on cylinder #2 somehow fell off of the spark plug, and I was driving on 7 cylinders all this time!
Secured it back in, fired her up and the sweet harmony and oomph returned :)

But on second thought,
1.  I might have been incredibly lucky the engine didn't hydro-lock as the injector would still have been dumping fuel into the cylinder all this time?

2. Or am I getting this wrong, and all that atomised, unburned fuel would have been easily cleared out the cylinder every cycle, and that was all the fuel stink out the tail pipe?

My vote is for number 2.  After my hydrolock adventures I learned that it's almost always fluid (whether fuel or coolant) pouring straight into the manifold.  So it was with me.  But you were washing a lot of fuel mist through that cylinder which could account for fuel smell.  :o  I'd change the oil, for sure.
-Dave
Now:  '76 6.9 Euro
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0