OMC 5.8L turning over but not firing

jwaagbo

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Jul 1, 2013
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Engine is a 92 5.8L OMC/Ford Windsor

I just had the heads re-machined and have put everything back together.

Tried turning it over and confirmed I am getting electrical from hooking up a timing light and seeing it flash.

I did not test the compression, but am planning to today. I lined the distributor up at TDC...

Any advice would be greatly appreciated. Thanks!
 

jwaagbo

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Jul 1, 2013
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Also this engine is 20+ years old so difficult to identify the exact markings on the vibration dampener.
 

Bondo

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Also this engine is 20+ years old so difficult to identify the exact markings on the vibration dampener.

Ayuh,..... Welcome Aboard,..... Is #1 sparkin' at or near Tdc, #1,..??
 

siego99344

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May 8, 2014
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look at the new post just went up the one with no spark its has alot of advice and that's how I got my boat to tuen on
 

siego99344

Petty Officer 2nd Class
Joined
May 8, 2014
Messages
150
look at the new post just went up the one with no spark its has alot of advice and that's how I got my boat to tuen on
 

jwaagbo

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Jul 1, 2013
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OK so got it running successfully and is running pretty good.

What is happening now is when I am running at WOT for a few minutes it starts back firing.

I just swapped out the fuel filter and tightened a couple nuts on the electronic ignition that helped a little bit as I am able to get to about 35 mph now.

Is it a fuel issue getting to the engine or timing do you think?
 

Bondo

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Messages
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OK so got it running successfully and is running pretty good.

What is happening now is when I am running at WOT for a few minutes it starts back firing.

I just swapped out the fuel filter and tightened a couple nuts on the electronic ignition that helped a little bit as I am able to get to about 35 mph now.

Is it a fuel issue getting to the engine or timing do you think?

Ayuh,..... Welcome Aboard,.... That's most usually caused by a Lean condition,.... Did ya inspect the Contents of the old filter,..??
 

jwaagbo

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Jul 1, 2013
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I unfortunately did not inspect the old filter.

So I was smelling Gas when the engine was idling so I thought it was too rich of a mixture.

I was able to time the engine properly now, but since I was smelling gas I leaned it down some yesterday and was running nice and quiet until I hit WOT again with the same results. Is there any tools I can use to get me to the proper mixture.
 

vinnie1234

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Jul 7, 2014
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161
The best way to be sure you have the proper mixture is by reading spark plugs. Unless you have an exhaust gas analyzer - then nevermind. But since most people don't have one of those just lyin' around, reading spark plugs is the next best thing.

Run your engine in for a while (3-5 minutes) in the RPM range where it is misfiring. Watch your thermostat because a lean condition burns a lot hotter. (as a side note: if you hear any knocking or pinging that could be fuel detonation from a hot combustion chamber so shut it down at that point.)

Once you shut it down, pop the hood and pull the plugs. Take a picture of each. A perfect mixture is going to show tan to light gray in colour. Lean conditions can be harder to figure from a reading, so go ahead and post pic's for some advice.

The best thing you could do is take your carb apart, clean it, adjust floats and put it back together by factory specs. That would get you closest to the correct mixture fastest.
 
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