1998 150 HP Johnson - cold starting etc.

epom

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I have a 1998 150 hp Johnson fuel injected engine with about 350 hours on it. The engine has a new solenoid, clean/new spark plugs and the wiring/connections have all been inspected and cleaned as of this past month. With that said, the engine has been giving us problems cold starting the past 2+ years. Typically if we prime the engine with the bulb it will start up after several times and from there the engine will run great. However, this problem has gotten progressively worse and we have been forced to spray the engine with engine fogger to get it started (especially on cold morning trips). In addition to that, the engine has started to run noticeably choppy at all speeds other than idle and the check engine alarm has been going off after running the engine for about 10 plus minutes (this started about 3 months back). The local marina hooked up their computer and they claim the check engine light is being set off due to water in the fuel. They checked the fuel and there wasn't any water. Their suggestion to us was to just keep running it as it is most likely a computer error with the engine. I however believe there is something more to this problem as the engine is running poorer and poorer on each subsequent trip.

We nearly always use 91 or 93 octane fuel and we always add the appropriate amount of Sta-bil ethanol treatment to any new gas we pump in. I'm rather confident there is not water in the fuel as it has been running poorly during the duration of multiple ill-ups at the gas dock.

The engine never dies, but it runs really rough and cold starting the thing keeps getting tougher. Any thoughts or suggestions? I understand there could be several things wrong and there are a lot of variables at play here but if anyone has some initial thoughts it would be greatly appreciated.

One last thing, the primer bulb is never completely hard when we pump it and it has not been replaced since purchasing the boat in 1999 (I would think this could contribute to the cold starting problem but I don?t know if this would have anything to do with the fact that it is not running smoothly).
Thanks in advance for any suggestions.
 

mekkamaz

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Dec 30, 2008
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Re: 1998 150 HP Johnson - cold starting etc.

Have you changed the fuel filter or the fuel pump? It sounds to me like a fuel pressure loss in your engine...Check for a clogged fuel line, a dirty fuel filter or a faulty fuel pump...the primer bulb issue sounds only like the check valve inside past away...
 

Silvertip

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Re: 1998 150 HP Johnson - cold starting etc.

Primer bulbs remain firm only until the engine is actually started. After that fuel is sucked through the line by the fuel pump. At no time should the bulb be sucked flat however.
 

epom

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Re: 1998 150 HP Johnson - cold starting etc.

Silvertip - The bulb is not sucked flat when the engine is running but my only concern with the bulb is that it doesn't get hard before starting which may contribute to the poor cold starting (especially because the fuel pump may be on it's way out).

mekkamaz - the water separator was changed last week, the fuel filter was changed last year (although it could be dirty again),
I haven't done a real inspection of the fuel line which I probably should do. I was actually thinking of hooking the engine up to one of those portable tanks with it's own fuel hose and seeing how it runs . . . I think the fuel pump is probably the most likely issue however. Any idea what that would run me to replace with parts and labor? Just a ballpark price . . . In the event that this has nothing to do with the fuel pump, filters or line do you think the fuel injectors are too worn? If that is the case I don't believe it would be cost effective to have them replaced but I could be wrong. Thoughts?
 

mekkamaz

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Re: 1998 150 HP Johnson - cold starting etc.

MMmmmm..Don?t have your exact model but for the year, ficht injection...has two pumps...elevation pump and a high pressure one...the elevation pump repair kit you can get it around $40, depend where you buy online....somewhere cheaper if you look right....you should start checking if that pump is delivering propper fuel pressure to the next pump...if it does....then a high press pump around $200....worn injectors on a 350 hr engine? don?t think so but as you know....parts does not have a word....do they? hehehe... you are willing to try maybe you can press the primer in order to bring fuel pressure up and check if it will get an instant of improvement...if you do, my guess will be elevation pump...what is a little confused is about the primer bulb not hardening...you shuld try a new one...good luck!!
 

CJ565

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Re: 1998 150 HP Johnson - cold starting etc.

I just sold my boat with 1998 175 Johnson Ficht outboard last may. It also had 350 hrs on it. I never had any problems with it so to speak. They say those Fight fuel injected motors were what brought OMC down. Lots of problems with them. I guess I got one of the good ones? Anyway, when my motor was running rough, I would put a knew set of plugs in it and PROPERLY INDEXED them!. By this I mean you need to take a sharpie marker and mark a straight line on the white ceramic part of the plug, in line with the open gap on the top of the plugs electrode. Then when you crew in the plugs, you need to make sure that the mark you put on the plug is pointed towards the fuel Injectors. This is c
alled indexing! Maybe I did this every 50 hrs? Or when the motor seemed to shimmy and shake more then usual. Before I sold my boat, I had the motor tested for compression etc... It got a clean bill of health, but the mechanic told me it needed a new set of plugs, told me it will run much better and smoother with them. It cost me maybe $90 bucks to have the motor looked over, plus a set of plugs and it was worth. But what I want you to know is the Mechanic told me that the Ficht outboards liked to go through spark plugs!.. I didn't know this, but with out knowing, on my own I would change them myself. The motor seemed to run smoother every time. I didn't know what else I could do much make sure the gas was always fresh, and that I would always check on the fuel water separator, and purge that. Only onve did I have a warning light come on when I was at a high altitude lake. I didn't know what to do, but when I pulled out all the fuses to check on them and put them back in again, I never had the warning horn beeping at me again. Good luck with your Outboard!

~Chris
 

epom

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Re: 1998 150 HP Johnson - cold starting etc.

Guys- thanks for all the advice. Unfortunately I have not had a chance to spend anytime with the engine as Connecticut has beena mess over the last week+ with power outages. Chris, my Dad in fact was told to index the spark plugs a while back and we've done that when changing the plugs ever since but we only change them once a year as I was under the assumption that that wasstandard practice. Plugs are relatively inexpensive so I think it makes sense to put a new set in. I'm thinking that between a new fuel line, new plugs, new bulb and a check of the fuel pumps we could resolve this issue. I'll let you know how we make out.

Thanks again for everyone's help!
 

Home Cookin'

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Re: 1998 150 HP Johnson - cold starting etc.

before I got to the mechanic's diagnosis, I said, "water in fuel." I struggled with a hard starting motor (Johnson 70) for years until finally it had enough and died from the water in the fuel.
try a portable tank with fresh fuel going directly to the engine.
 
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