'97 Mercury 150 EFI multiple issues

rebelroy11

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Engine idles fine for the most part. When I put it in gear it dies a lot. Sometime I have to give it gas and shift it in FWD then tap the hot foot to keep it running. Once I have it in gear and running I have to ease on the throttle or it will die or start to bog down. If were to just hammer on it, it would bog down and eventually die. But were to ease on the throttle until full throttle I would only get about 2300 rpms at the floor and maybe 10 mph instead of the usual 55-60mpg. The engine is on a 19ft Basscat Sabre. It ran like a top before sitting up for a few months. Last used ethanol gas with Stabil. Only thing I've had time to do it is change plugs, compression check (ok), added Seafoam treatment, and pulled filter and currently ordering a new one. Fuel line is alcohol resistant and seems fine. Bulb doesnt really get tight but never really has. Brand new fuel pump was installed April of last year.

Also I noticed after taking it out this past weekend that there was some "leakage" from the stator. At the time it looked like oil. The next day I looked at it again and it had dried to crust leading me to believe it was wax. Is this normal?

Also at idle I'm only getting about a voltage read of about 9 volts on the dash. It doesnt go about 12 until I give it gas. Is this normal?

Sorry guys I know enough about outboards to get myself in trouble and enough to fix it myself with a lot info from you guys. The top two problems are most important. Thanks in advance.
 

Dukedog

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Re: '97 Mercury 150 EFI multiple issues

First and "probably" tha cause of your problems is tha stator. Replace it. Check both regulators and trigger. Probably ok but check 'em anyway. Set of new BU8H's. Throw tha idle speed controller away and reset max timing....Set idle timing with motor runnin', in gear, on tha water. That should do it but we're on a computer so it ain't a 100%...................jmo
 
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rebelroy11

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Re: '97 Mercury 150 EFI multiple issues

First and "probably" tha cause of your problems is tha stator. Replace it. Check both regulators and trigger. Probably ok but check 'em anyway. Set of new BU8H's. Throw tha idle speed controller away and reset max timing....Set idle timing with motor runnin', in gear, on tha water. That should do it but we're on a computer so it ain't a 100%...................jmo

I ran the motor and decided to pull the boots of the plugs and see for change in rpm. Cylinders 1, 2, and 6 had no change. Motor died or ran horribly when pulling the other. I purchased a spark tester and it showed cyl 1 and cyl 6 had no spark but would not run for but a few seconds when connect to cyl 2 but showed it had spark. At least some but not NONE like the other two. I switch wires around and still had the same problems in same areas. I've read that if it was a stator or trigger problem then it would all be related to the same bank of cylinders and not both like mine. Could be just a few individual coils have gone bad, even though it seems odd? Or do you think its still at a stator or trigger problem?
 

Dukedog

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Re: '97 Mercury 150 EFI multiple issues

One or more on tha same side usually a switch box. One or more oppsite sides usually a stator since triggers are usually tha most dependable 'lectric part on tha motor other than tha coils. That doesn't rule out either one of 'em though. Stator needs ta be checked with a dva but like tha trigger it will sometimes show up with just an ohms test.......But ya say ya got some "leakage". That's pretty much a dead giveaway..........Check your regulators also. Look for burn/discolored spots and burnt connectors on 'em..........
 

rebelroy11

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Re: '97 Mercury 150 EFI multiple issues

Yeah. The odd thing is that the first time I took it out there was no leakage. Not noticeable anyway. I'm hoping its just one problem and not multiple as in the switchboxes and stator. I'm hoping that if its the switch box that by me running it hard in that condition just caused the stator to be taxed and maybe overheat a little and still be fine. Being my luck though...not likely. Thanks for the help. From what you've said and based on my recent study in these situations I tend to agree with your analysis. One more question though. I have two switche boxes. If I were to see the problem only coming from one, is it ok to change just the problem child or is it best to change both?
 

Dukedog

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Re: '97 Mercury 150 EFI multiple issues

Best ta change both. Some get away with just one but usually end up with tha same scenario on down tha line........Change tha stator first. That's a given at this point............If you run across a trigger cheap ya might wanna change it to while your there. At least ohm it out. Any V6 trigger prior ta 2000 will work..............
 

rebelroy11

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Re: '97 Mercury 150 EFI multiple issues

Best ta change both. Some get away with just one but usually end up with tha same scenario on down tha line........Change tha stator first. That's a given at this point............If you run across a trigger cheap ya might wanna change it to while your there. At least ohm it out. Any V6 trigger prior ta 2000 will work..............

Thanks again!
 

Dukedog

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Re: '97 Mercury 150 EFI multiple issues

Rectifier and regulator are one in tha same. You have two of 'em. Mounted under tha coil plate...........


Number 7 on tha Brunswick/Merc site.....
 
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