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Right hand rotation firing order on OMC 3.8 liter v6 4 barrel carb.

6

60grit

Member
I have a 1982 Sea Ray 245 Sundancer. It has the twin OMC 3.8 liter v6 motors with 4 barrel quadrajet carbs. The port motor has a tag on the port valve cover with a model number of 384STMRCNC. I believe this is a right hand rotation motor on the prop. I believe the firing order from the manual is 1-6-5-4-3-2. The manual shows the the port forward #1 plug wire being oriented to the forward connector on the distributor cap. My motor is not wired this way. My # 1 plug wire is wire to the back of the distributor.The firing order seems to be the same , but when I rotate the balancer around and match up top dead center with the timing marks my rotor is not pointing to the # 1 cylinder. Is this a left hand motor? What is the process to time this motor? Any help is appreciated. I have researched other threads , but I am not coming up with reasoning.
 
dist rotors may or may not point to any particular part of the engine.
I know of no V6 as counter rotation nor a omc drive as counter rotation
Are both motor now running, compare firing orders , in a clockwise direction 1,6,5,4,3,2
Engine rotation is viewed from the flywheel , standard rotation is to the left, but prop turns to the right
 
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Remove the port valve cover, rotate the motor watching the second rocker arm. When it opens the valve and then closes the valve your on the intake stroke, turn motor untill harmonic balancer line is at the 0 timing mark, If the cap is marked #1 install dist with rotor pointing to #1 in the cap , install dist mating up the oil pump shaft.Using a long wide screwdriver insert into oil pump shaft and turn to line it up with the dist , install dist and hold down clamp,
install cap, start and check/reset the timing
 
I have never see a counter rotating V6 so it has to be a standard motor , flywheel turns to the left, harmonic balancer to the right as viewed from the front of the engine
In what direction do the harmonic balancers spin .Clockwise as viewed from the front of the engine?
 
The harmonic balancer turns clockwise looking fro the front. Don not understand why the plug wires and distributor are not hooked up as it states in the factory manual
 

Listen to Bt Doctour....... he is giving you great advice!


I am not aware of OMC doing a Cobra drive for a RH REV Rotation Engine.

I too know of no RH REV Rotation V-6...... only STANDARD LH Rotation.

Rotation is viewed from the Flywheel End..... not the front end.
A standard LH Rotation Engine's flywheel will turn in a CCW direction when viewed from the flywheel end.

If you DID have a REV RH Rotation Engine, the firing order would be reversed (starting @ #1 cylinder), and the ignition distributor would rotate as NORMAL.



Don not understand why the plug wires and distributor are not hooked up as it states in the factory manual
Click to expand...

Although this is not what I would do...... it makes little difference how the distributor is indexed. With #1 cylinder at TDC on the C/S ONLY........ begin laying out your spark plug cables. For me..... I would index so that the rotor would be aiming towards the physical location of #1 cylinder..... but like said, it is not completely necessary!
The only engine whereby this would make a difference, would be the early "Odd Fire" V-6.


 
maybe somebody was careless and just dropped it back in and reconfigured the plug wire to get it to run
I had a job on a 454 that somebody did the same thing. Unknown to me I just pull all the wires off the cap, did what I had to , installed the wires according to the caps numbering and the motor would not run. Try as I might it would not fire. So before removing the dist I decided to remove the #1 spark plug and crank the engine listening for the rush of air. Watching the rotor It corrosponded to position #5 in the cap. Using that post as #1 and a clockwise
wiring pattern the motor fired right up.
So when the testing was done the dist was removed and indexed to the proper position
 
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I get it. Thank you for your time and input. Ran motor on Dyno this morning all is good. New to the OMC World, just trying to understand what I have. I have been a member since 2009 and have received a lot of help,so thank you. Just got out of twin Chryslers and in a new boat with the OMC v6s. A glutton for punishment I guess.
 
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