2.3L OMC timing curve

I have an 89 OMC 2.3L in my boat. I am getting ready to pull the distributor out and replace the springs. I have a dead spot on initial acceleration and I am going to replace the points with a pointless ignition and flame thrower coil with a resistor. I have rebuilt the carb and it did nothing but run smoother but did not fix hole shot. I am going to purchase a re manufactured carb. The boat runs awesome just; except that one small problem. I know that the timing at an idle is 10 degree BTDC but I do not know how fast the timing should advance and how far it should advance. What is the Max timing advance? I have looked in the book but am unable to find it. How fast should the timing advance from Idle to 1800rpm?

Re: 2.3L OMC timing curve

I have a 2.3 also. Rebuilt the carb over the winter had a hell of a vibration on throttle increase. (Clogged venturi) see below. Some problems with timing, also major carb issues. Boat sat for a bit before I bought it. Dirt in Venturi tubes causing 1 of the air adjust screws to do nothing, when trying to adjust. dirt in bowl, leaking gaskets at base, and top causing internal air leaks, cleaned all up and runs like a top on the muffs, can't wait to test her in the drink. I too was going to go pointless, did a lot of reading, probably won't help performance wise, so I just went with new points and condenser. Also put a spare coil in the glovebox. I would look down the carb when you throttle up, even with boat off, you should see 2 strong streams of fuel at top spraying at 45 deg. Angle into bowl, having a clogged Venturi cluster will cause a flat spot hesitation. These help deliver proper flow of needed fuel to a engine from hole shot. Also if your going to new ignition you will need the ESA switch for shift. I think petronix has a link on the website for the wire set up needed to achieve this. Keep us posted. Oh btw I am running a 17' donzi I am seeing a speed with my gps of 29-30. Speedo is now working I will see what the says on maiden voyage this year. Also have some dings in the prop going to work on that and see if it helps, also with vibration too. What is your boat and speed. Wot?

Re: 2.3L OMC timing curve

Re: 2.3L OMC timing curve

Thank you for the responses. The diagram was exactly what I was looking for.

The carb works great, I get the two full streams on acceleration. I am replacing it due to the stream does not start right away on the movement of the throttle cable. Also the flaps in the bottom have up and down play in the them creating a small vaccuum leak. I got the pointless system right from mallory along with the spring kit and they told me which resistor I need to put in with what coil I am using. The boat does perform great, When I bought it the engine was replaced with a Jasper rebuild and only had 10 hours on it and the outdrive was gone through with all new bearing and seals also new lower gears and had only 8 hours on it when I got it. The boat is 19' Bayliner. I am running a SS 4 blade 17 pitch. WOT throttle is 5400 rpm @ 41 mph. I am considering changing my prop to an aluminum 4 blade 17 pitch but am waiting until I finish with last of the repairs I want to make.

Re: 2.3L OMC timing curve

armydrill said:

Thank you for the responses. The diagram was exactly what I was looking for.

The carb works great, I get the two full streams on acceleration. I am replacing it due to the stream does not start right away on the movement of the throttle cable. Also the flaps in the bottom have up and down play in the them creating a small vaccuum leak. I got the pointless system right from mallory along with the spring kit and they told me which resistor I need to put in with what coil I am using. The boat does perform great, When I bought it the engine was replaced with a Jasper rebuild and only had 10 hours on it and the outdrive was gone through with all new bearing and seals also new lower gears and had only 8 hours on it when I got it. The boat is 19' Bayliner. I am running a SS 4 blade 17 pitch. WOT throttle is 5400 rpm @ 41 mph. I am considering changing my prop to an aluminum 4 blade 17 pitch but am waiting until I finish with last of the repairs I want to make.

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Thanks for the #'s. i got a 3 blade alumium, not sure if its a 15 or 17, but gonna make some change to it for more speed. ofcourse that was tested with my gps, will see what my speedo reads this year. i took my friend out with me and did all my testing and adjustments to timing/carb on water under full load. although timing should not change, land vs. water? I hve put heavier springs on my classic car dist. before, without pulling the distributor. small noticeable change. in my head anyway. put in fresh plugs too, also you may want to take a dvom and ohms test resistance in your spark plug wires to make sure they read all pretty equal. 1 or all, might have high resistance? so while your on the ignition side of things, check it out. goodluck!

Re: 2.3L OMC timing curve

I would also check and make sure that the accelerator pump is giving a good shot of gas when you jump on it.. that sounds like it could be your problem - or of course the dreaded cable drag on the shift cable... could be pulling the contact switch over and engaging the esa when you try and get out of the hole...

Re: 2.3L OMC timing curve

Reinell-BRXL-191 said:

or of course the dreaded cable drag on the shift cable... could be pulling the contact switch over and engaging the esa when you try and get out of the hole...

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By the time you are actually introducing throttle,the shifting is done so that shouldn't be an issue. If the ESA was actually engaging, the engine is barely going to run at all.