16 Amp 2.4 EFI Bridgeport should it charge the battery?

[redpickle]

I have a 1987 2.4 Efi Bridgeport that is not charging. I just had the stator, trigger, rectifier, and volatage regulator replaced with genuine mercury parts. With a 16 amp stator should it charge the battery slightly? I but a meter on the battery with the motor turned off and had 12.76 volts. While idiling it was 12.46 volts. I would check it periodically while I was out and each time I checked it at idle (1200 rpm) the voltage would be a little lower each time 12.46 then 12.43 then 12.39 ect. No extra electronics were being used except for the fuel pump. I was told years ago that the stators on the high performance motors did not charge enough to run extra electronics but did not think that meant they do not have the output to even maintain a charge. Is this correct? If it should be charging what else should I check? About every piece of the charging system has been replaced.

[pyro]

It won't put much significant voltage back in unless you're running above idle. I always put a battery charger on after a run.

Read the voltage again at 3500 rpm.

Mine doesn't even have a regulator. The rectifier is wired directly to the 12v bus.

[Glasstream15]

I have a Tower with a 9 amp stator. I run 2 depth finders and a small stereo and it keeps the battery charged quite well. 14 amp should charge well at 1500 + revs.

[pyro]

Maybe on a carb motor it does. Fuel pump and ECU together can draw more than 10 amps.

[TEXAS20225]

the 16 amp systems when working correctly with a regulator will put out 14 volts, without a reg it will put out 15-16 volts thats merc stuff not cdi im not sure what they put out something is not working on yours or it would be charging

[Varmint]

something isn't right,I can fish a 12 hour day in my shadow,w/Bridgeport,and it runs,livewell,bilge pumps,fuel pump ,offshore trim pump,all the gauges,nav lights,stereo, I only use the 1 battery for cranking and 3 (36v system) for troller., I used to worry I would have to borrow a trolling motor battery at the end of the day,but never have had to.

[donmac]

Maybe on a carb motor it does. Fuel pump and ECU together can draw more than 10 amps.X2 ,they just don't put out enough amps unless your above 3000rpm! they should have come with a bat. charger in the carton!

[stevo18]

same here mine only charges over 3k

[dbug10]

Mine also 3000 RPMs

[redpickle]

I checked it today over 3000 rpms and it does not show its charging. I had a mechanic friend of mine call mercury and they were no help either. He talked to a merc engineer and they said these motors were known for not charging well. He said the 16 amps is rated at wot. I think we all knew they don't charge well with only a 16 amp stator. My question is should it not at least maintain a charge while cruising around? Merc could not answer (or would not answer) what voltage it should put out at xxx rpm. We are going to go back and retest the parts we just replaced to see if one is bad.

[pyro]

The battery will slowly discharge as you run. It should still go for 4-5 hours without getting too low.

[donmac]

it should maintain if lake running! the Weldon pumps that came with the offshores took a lot of juice! I'm sure they run about 15-16 volts running near wot,but I've never amped one! I always had the charger on them, trim pumps,center tab pump,vdo gyro compass,injection fuel pumps with purge tank pumps! DON'T SHUT IT OFF!

[TEXAS20225]

im not sure what is up with all this not charging business a whole lot of the fishing motors had 16 amp charging system in the 80's ?? i had 2 150's in the mid 80's with 16 amp charging systems they did not require any extra attenion to keep running off a single battery live wells depth finder and so on i also had a couple of 260's which were 16amp also as well as a 280 with drag electrics on it i never had any of the things you guys are talking about

[donmac]

im not sure what is up with all this not charging business a whole lot of the fishing motors had 16 amp charging system in the 80's ?? i had 2 150's in the mid 80's with 16 amp charging systems they did not require any extra attenion to keep running off a single battery live wells depth finder and so on i also had a couple of 260's which were 16amp also as well as a 280 with drag electrics on it i never had any of the things you guys are talking aboutyou must have had the texas 16 amp [it's bigger], don't most fishing boats have isolator's on the trolling and well batt's

[bigbluechevy454]

My 16 amp doesnt do much for charging my rig i always precharge before i go out

[twokoop]

YEA but how long does it last???

[pyro]

im not sure what is up with all this not charging business a whole lot of the fishing motors had 16 amp charging system in the 80's ?? i had 2 150's in the mid 80's with 16 amp charging systems they did not require any extra attenion to keep running off a single battery live wells depth finder and so on i also had a couple of 260's which were 16amp also as well as a 280 with drag electrics on it i never had any of the things you guys are talking about

Inconsistent component quality and performance results in some 16 amp charge systems working better than others. Stator windings aren't always wound exactly alike, and the magnets can have varying strength. 150's never had a charging problem because they didn't have electric fuel pumps and ECU's.

My volt gauge never reads over 12-13 volts, even at WOT, unless I'm hooked up to the charger.

[skipe]

My 89 Bridgeport runs 14-16 volts over 3000 rpm but it has to be there more than 15 minutes before the guage starts to climb.

[twokoop]

Inconsistent component quality and performance results in some 16 amp charge systems working better than others. Stator windings aren't always wound exactly alike, and the magnets can have varying strength. 150's never had a charging problem because they didn't have electric fuel pumps and ECU's.

My volt gauge never reads over 12-13 volts, even at WOT, unless I'm hooked up to the charger.

maybe I should run a really long extension cord to the back of my boat

[FUJIMO]

These 80's EFI motors came out of race division. They were meant for use with race boats, never for pleasure use. Enjoy.

[luv2gofast]

Mine always charged fine as long as I didn't start it too many times without making a long run. The only times that I had a problem were when I was teaching skiing where I was idling and starting a bunch of times without a good run. I did have the regulator fail twice and the rectifier fail once. You should see a fairly high voltage across the two yellow wires on an AC volts scale where they attach to the rectifier. That is the direct voltage from the stator which is AC not DC so switch your meter to an AC scale. If that is good (14 -15 vac) when above 2500 RPM then check the output of the rectifier. It will be less but should still be 13 to 14vdc above 2500 RPM. If the AC voltage is not going up with RPM, You can disconnect the regultor as long as you don't run the RPMs up too high. If the voltage goes up with the regulator disconnected then the regulator is bad. The way it works is the regulator senses the DC voltage on the red wire and partially shorts the output of the stator, yellow wire to ground to keep the DC voltage from going too high at high RPMs. When the regulator fails it shorts the stator to ground all the time.

[ratman67]

I don’t plan more than a CD player and pair of speakers and will run total loss separate battery to power it, where I boat there are zero no wake zones so little idling, all my runs will be 20 mins or more so very little stopping starting. Doesn’t an aftermarket company make a better charging system for this engine?
Any other problematic things to look for as far stuff that should be updated or upgraded? Thx for all this great info guys. Where I will be boating getting stranded would suck! Thx again guys

[W2F a V-King]

I have a 1987 2.4 Efi Bridgeport that is not charging. I just had the stator, trigger, rectifier, and volatage regulator replaced with genuine mercury parts. With a 16 amp stator should it charge the battery slightly? I but a meter on the battery with the motor turned off and had 12.76 volts. While idiling it was 12.46 volts. I would check it periodically while I was out and each time I checked it at idle (1200 rpm) the voltage would be a little lower each time 12.46 then 12.43 then 12.39 ect. No extra electronics were being used except for the fuel pump. I was told years ago that the stators on the high performance motors did not charge enough to run extra electronics but did not think that meant they do not have the output to even maintain a charge. Is this correct? If it should be charging what else should I check? About every piece of the charging system has been replaced.

Just because I didn't see where the battery was tested? And what kind?

You have tested/replaced everything you can, save for the battery and maybe try a different flywheel, that's where the magnets are that produce the magnetic field that induces the voltage into the stator winding's...

[90 5.0]

On my carb 16 amp motor with light flywheel and some electronics, one 5” lowrance, tach and other gauges. Trim comp, trim pump etc it never has an issue.

On my old carb 2.0 with 16 amp on dad’s old bass boat with manual fuel pump we fished tournaments around the country with no issues ever.

On my efi promax the 16 amp lasts a few hours playing on the bayou and fishing for short periods of time. If I’m gonna Fish all day we put the 40 amp back on.

Even just cruising with no fishing its draining the battery at cruise with efi and electric fuel pumps trim pumps etc etc

and these are all with big fishing batteries, group 24-27, nkt light weight race bats

[Krazymaan]

Same here. My 16 amp 2.4 has never given out. 3 years now, never needed a charge or jump. Not even after being frozen all winter long and hooked up. It also registers under 13 v like yours. Although I do have carbs.