2.3l omc esa module help

[fordsohc46]

i have an 87 or 88 2.3l omc I just bought. the serial number is gone but the boat is an 88. it will start and run but after a while it starts missing and it is only firing on #2 and #4 I can tell because my timing light wont pick up on #1 and #3. after searching these threads I have narrowed it down to the esa. when it does it I can unplug the two wire connector and it straightens up and runs great. if it cools down I can plug esa back up and it will run fine for a few minutes. Also if I manual push the switch for esa while it is idling fine it kills the motor. the way I understand it it should just cut fire to some cyl. and cause a stumble not to totally die. I just wanted some other opinions before I deemed the esa bad and also wanted opinions on which esa to get and part #'s would be appreciated. I may put a pertronix ignitor in in the future so I am leaning towards the cdi.

Thanks,
Paul

 

[HT32BSX115]

i have an 87 or 88 2.3l omc I just bought. the serial number is gone but the boat is an 88. it will start and run but after a while it starts missing and it is only firing on #2 and #4 I can tell because my timing light wont pick up on #1 and #3. after searching these threads I have narrowed it down to the esa. when it does it I can unplug the two wire connector and it straightens up and runs great. if it cools down I can plug esa back up and it will run fine for a few minutes. Also if I manual push the switch for esa while it is idling fine it kills the motor. the way I understand it it should just cut fire to some cyl. and cause a stumble not to totally die. I just wanted some other opinions before I deemed the esa bad and also wanted opinions on which esa to get and part #'s would be appreciated. I may put a pertronix ignitor in in the future so I am leaning towards the cdi.

Thanks,
Paul

Howdy Paul,

Your engine being an 87 or 88 probably doesn't make much difference. You can view part numbers at http://epc.brp.com/ (email not needed)

OMC changed the part number for that ESA 2 or more times and the CDI will certainly work. It shouldn't kill the engine at idle RPM though, and it doesn't just cut ignition to a couple of cyls. It actually "pulses" the ignition such that the engine should "lope" to make it possible to pull the clutch dogs apart during a "torque-LOW" while applying "pull-apart" tension on the "dogs" via the lower shift cable.

It makes cable and shift plate adjustment fairly critical to get all this stuff working correctly. On that note, I suggest you get yourself an OEM manual that covers your engine and drive. (I think the 88 is good for the 87 also) In addition, have a good look at the following info, http://www.hastings.org/~stuart/cobra/ There a great description on care and operating of a dog-clutch Cobra.

Once you determine that your shift system is adjusted correctly and you have determined that the ESA is defective and it works with the new one, you can do the ignition MOD. (I think the CDI comes with instructions for making it work with a Pertronix or other electronic Ign system)

Cheers,


Rick

 

[fordsohc46]

Rick,
thanks for reply. I have adjusted cable per stuart instructions. oddly the po gave me a manual and had this link you provided printed off and stuck in the manual. He had obviously tried to adjust but was unsuccessful. I have it adjusted pretty good now and it will even go in and out of gear pretty smoothly with esa unhooked. the fact that it starts running bad and I unplug esa it straightens out leads me to think it is bad. what do you think? so would all cdi esa's work on this motor? what I see from them is they are all the same on 4cy. v6 and v8

Paul

 

[HT32BSX115]

Rick,
thanks for reply. I have adjusted cable per stuart instructions. oddly the po gave me a manual and had this link you provided printed off and stuck in the manual. He had obviously tried to adjust but was unsuccessful. I have it adjusted pretty good now and it will even go in and out of gear pretty smoothly with esa unhooked. the fact that it starts running bad and I unplug esa it straightens out leads me to think it is bad. what do you think? so would all cdi esa's work on this motor? what I see from them is they are all the same on 4cy. v6 and v8

Paul

Goes in and out of gear on the trailer or in the water? There is a HUGE difference. They'll ALWAYS go in and out of gear OUT of the water without ESA operation since there's no appreciable torque on the clutch dogs.

Another whole "thing" IN the water. (and that's the only way you successfully can test shifting)

The CDI ESA's are essentially THE replacement ESA for all of early ones. According to BRP the replacement is OMC #0984281 replaced by #0985902

And according to MarineEngine dot com

[h=1]18-5890 - MODULE, 987740[/h] Replaces OEM #0987740. SHIFT ASSIST MODULE & HARNESS Replaces: 987740 For: V-6 Sterndrives Fits: 2.3, 3.0, 4.3 (1986-90) & 2.5 (1986)
Part Number 18-5890	Manufacturer Sierra Marine

There were some changes in how they operate introduced in later years due to adding an "over-stroke" switch etc. I think the the newer ESA's take advantage of this switch (if you have it) I would get the Sierra [CDI] ESA (you can probably even buy it right here on iBoats)

Amazon even has it and a search will produce the cheapest price and shipping etc.

 

[fordsohc46]

I do have the overstroke switch. so I should get the sierra cdi one? this one would let me switch to pertronix if I chose to later correct?

I am testing it out of the water. that is good info to know. I will try to get it down to the river this weekend and see if it shifts as easily in the water. do I have to have boat under way or could it be tested on the trailer but outdrive submerged in water like on boat ramp?

 

[HT32BSX115]

I do have the overstroke switch. so I should get the sierra cdi one? this one would let me switch to pertronix if I chose to later correct?

I am testing it out of the water. that is good info to know. I will try to get it down to the river this weekend and see if it shifts as easily in the water. do I have to have boat under way or could it be tested on the trailer but outdrive submerged in water like on boat ramp?

The one sold by Sierra is the CDI ESA. I don't think anyone else makes them.

To test, you MUST have the boat in the water. You can tether it to a dock or be out on the water......it doesn't matter. The only way to test shifting and shift plate actuation is to have the prop in the water so that it's (torque) "loaded".

Here's the CDI ESA that replaces yours (directly from CDI)
http://www.cdielectronics.com/produ...-986837-987738-987739-987740-18-5888-9-24500/

You might contact CDI to see if they have a electronic points "replacement". If they don't, you can verify that this ESA will work out of the box with the Pertronix II ignitor or if you need to do any sort of mods.

Since points are pretty reliable, you might just consider sticking with the points.

 

[Papalax]

I just went thru this (and a couple of additional issues) with my 1988 OMC 4.3 (Model 434APRGDP, also a second sticker with model 985269??). It starts and idles great, but won't go over 2000 RPM (another thread I think). Then last week, was backing away from dock and was hard to get into neutral and would not shift into forward. Got back to dock. Shifted fine with engine off (so cable was not stuck/binding). Did some research and narrowed it down to ESA and ignition interrupter. Saw interruption was not functioning "normally" between the "V" grooves according to a few videos. I cleaned the switch, better but not quite. Looked into a new ESA on-line and a couple of local marina shops and I found one in stock.
My original is part number 984036. I determined it was superseded by part number 987740 (verified by two separate marina stores as well).

Had the wife pick it up when she was out and got to replacing it the next day. When I got the original one off, the wiring connection was not in the same location, and it had longer bolts than what I took off. Mine mounted flush to the bracket, so it seemed to be an issue - new bracket, drilling/cutting old one, etc. I also noticed the new part number was different than the part number on the box it came in. Called marina and they apologized, but not sure how that happened. (Maybe not too relevant, but a good "note to self" to at least check numbers, as I live almost an hour from the store). They did have a Sierra part in stock at warehouse.

Went back next day for new part. It had same wiring configuration. Had them double check part numbers and they determined it was the correct replacement ESA. One the way home, it dawned on me. The longer bolts and spacers were to allow the wiring in the new location to be routed behind the ESA and fit through the hole...

Installed the new ESA and shifting great now. It does have a bit more of an RPM "skip" than before. Not sure if that is what it is supposed to be, but will see how she runs this weekend and then might go after the shift interceptor switch next.

Still does not go over 2000 RPM... :-(. Starts and idles fine up to about 1800 RPM. Will get to wide open for about 5-10 seconds when cold though.

For this so far, previous owner:
* replaced tank and engine fuel lines
* carb cleaned

I ran sea foam thru for about a tank full at the slow speeds and it seemed to get a tiny bit better. I wanted to use it more this weekend so I:
* had cleaned carb
* replaced corroded anti siphon valve
* replaced fuel pick-up hose
* replaced fuel/water separator filter
* just replaced fuel pump (mechanical)

Still bogging down at 2000. I will be checking vent hoses and listen more for any vacuum air-sucking noises more this morning. Still unclear if ESA/Shift interrupter issues is related to bogging down. Some suggest it is. If not, am at a loss, other than a complete carb rebuild next. Wondering if anything obvious (or not) I could be (am) missing. Thanks.
John