My Force 150 failed me (again)

johnbottsr

Petty Officer 2nd Class
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Oct 6, 2012
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104
Two weeks back to back.
Last week I was sure it was the battery so I bought a new one.
This week I started it on the muffs and got it warmed up before I left the house.
Got down to the lake (Ft. Spokane launch on Roosevelt which sucked) and fired her up still on the trailer.
So far, so good.

Got running up river and she died (after running pretty well to that point).
Fired her back up and off again - DIED.
I looked back right after to see her easing back down from being trimmed up (?).

Happened a third time (with the trim thing) and then no more start.

To make matters worse, my kicker would not hold prime (again) as the fitting I put on there last week to limp to the launch must have decided it was a good time to not seal.

ANYWAY, I plumbed the gas line from the main motor (dead Force 150) to the kicker and made it back.

However, I have no clue why the Force dies on me.
I plan on getting a compression tester tomorrow and I have the shop manual but no clue where to start troubleshooting.

I thought maybe the battery I bought was DOA but it jumped right to 98% when I put it on the charger after this episode.

BOATING IS FUN!
 

pnwboat

Rear Admiral
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Oct 8, 2007
Messages
4,251
Re: My Force 150 failed me (again)

What year is your motor? Sounds like it might be loosing spark??? Early 150's used the Prestolite ignition system with the blue coils and CD modules. Later versions used the Mercury ThunderBolt with the Dark blue coils(almost black) and a switch box. There are two versions of the Thunderbolt ignition system One that uses a battery voltage converter to drive the switch box, and another that uses the stator generated voltage to drive the switch box. Based on your symptoms, my guess is that yours is probably one of the Mercury ThunderBolt versions.
 

johnbottsr

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Re: My Force 150 failed me (again)

1991J engine.
Manual says it is the Thunderbolt system.
 

jerryjerry05

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18,072
Re: My Force 150 failed me (again)

Is it getting hot? Test the overheat system?
That motor came with 2 ignition systems.
Post a pic or include serial#s model# ?
The fuel system,the primer/enricher has a diaphram in it that can go bad and cause the symptoms your suffering.
That motor has 2 fuel pumps and 2 types of fuel pumps on that motor.
It 's possible one or both need a rebuild.
The inline connectors can go bad and suck air.
 

pnwboat

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Re: My Force 150 failed me (again)

Looks like this model uses the battery converter with the switch box for the ignition system. The stator on this model is only used to charge the battery. First thing to do is to verify that it has good compression, good spark and fuel.
 

johnbottsr

Petty Officer 2nd Class
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Oct 6, 2012
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Re: My Force 150 failed me (again)

I'm going to try and borrow a compression tester and check it today.
I probably should have been more clear that after the third time it dies it not only would not start, turning the ignition key did NOTHING. No click, nothing. That is why I suspected the battery but now I think I need to check that starter first (unless the ignition switches are notorious for going out).

Also, the losing prime was on my kicker motor, not the 150.
I will check the fuel pumps out but I think I'll start at electrical (assuming the compression tests OK).
 

pnwboat

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Oct 8, 2007
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Re: My Force 150 failed me (again)

Ahh that's a little different. The neutral safety switch may be out of adjustment. When it does this (won't turn over), jiggle the throttle handle or move it back and forth and see if that does anything.
 

johnbottsr

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Re: My Force 150 failed me (again)

I jiggled the Hell out of it to no avail . . .

I think I have a couple of issues here.
 

SweeperForce

Chief Petty Officer
Joined
Feb 7, 2010
Messages
487
Re: My Force 150 failed me (again)

I'm with pnwboat about the neutral safety switch see pic.
Enigine pics_0010ABC.jpg
The cam has to push in the white pin. Also make sure your circuit breaker didn't pop.
Force electic_0002AB.jpgForce electic_0011Caw.JPG

Hope this helps,
Tom
 

pnwboat

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Re: My Force 150 failed me (again)

Could also be a bad connection between the neutral safety switch and the starter solenoid. You can by pass all that by just taking a pair of pliers or a wire and shorting between the terminal on the starter solenoid that has the small yellow wire and the cable that comes from the battery. You'll get a pretty good spark but if the starter kicks in, then you know that the problem is somewhere in the wiring before the solenoid.
 

johnbottsr

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Oct 6, 2012
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Re: My Force 150 failed me (again)

OK, thanks guys.
Probably be raining when I get home so I don't think I want to do many electrical checks today (boat is outside).
 

johnbottsr

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Re: My Force 150 failed me (again)

Well I checked the NSS and the circuit breaker and had continuity through both of them.
Still haven't laid hands on a compression tester and may just break down and buy one.

Should be able to do some more tests this weekend.

The cooling system makes sense to me currently.
I will get some gasket material and pull the thermostat this weekend too.
I just replaced the impeller and was pumping good. The water did get warm from the exhaust bypass thingy on the leg running on the muffs though - does that mean the thermostat opened?

My buddy seems to think the motor rides too low in the water and is getting the ignition system wet causing the stalling - opinions on this theory?

Anyway, wanted to let you guys know I haven't given up, just busy lately.

EDIT: BTW, Model # is 1501X91J
SN# is 025880
 

jerryjerry05

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May 7, 2008
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18,072
Re: My Force 150 failed me (again)

Your buddys probably wrong. You'd have to dunk it to make it stall from water.
You test the temp sender? Simple test,key on.ground out the orange lead at the harness connection block. Should make the buzzer sound off.If the buzzers workin it probably didn't overheat, Check the sending unit.
Saw a factory mnual for the Force 150 91 on e-bay. I believe it was under 20$
I bought one 3-4 weeks ago for 12$
 

pnwboat

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Re: My Force 150 failed me (again)

If you need a compression tester let me know.

If you got warm water coming out of the two exhaust by-pass holes while on muffs, then you've got water flowing through the block. Water temperature should be fairly close to what ever the thermostat is rated at 130? - 143?.

About your problem with the motor dieing and then nothing happening when you turn the ignition key. You might be fighting two separate problems. Intermittent motor start circuit problem, and intermittent ignition system problem. Need to eliminate one of then to see if they are related or completely separate problems. Since you have a battery powered ignition system, there is a possibility the two problems are related. You did say the you replaced the battery didn't you?

The intermittent start problem where you turn the key and nothing happens could be the wiring between the NSS and the starter solenoid, or the solenoid itself ( I've got a used one laying around somewhere). Wiring between the ignition switch and the motor (check the wires on the back of the switch to make sure they are connected good and firm), or maybe the ignition switch itself. Try spraying some contact cleaner into the ignition switch. Usually you can find and opening on the back of the switch to get some contact cleaner into the inside of the switch. Might even be a bad battery cable/connection.

If you do have an intermittent ignition problem, that could be a bad ignition system ground, bad battery converter box, or bad switch box. Your stator doesn't have anything to do with the ignition system on this motor since it is a battery powered ignition system.

Intermittent problems can be tough to fix since the problem isn't always present, but anything can be fixed. Just need a little patience.
 

johnbottsr

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Messages
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Re: My Force 150 failed me (again)

Thanks guys, I do have the factory manual so I can run the entire ignition troubleshooting routine.
I didn't see how to check the alarm so I will do that soon based on Jerry's advice.

Might not be a bad idea to just spray everything down with contact cleaner, huh? I am a true believer in it after it fixed lighting problems on my camper last weekend. I'll snag a can tonight.

Yes, brand new battery.

I might take you up on that compression tester pwn, that is a nice gesture.
 

johnbottsr

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Messages
104
Re: My Force 150 failed me (again)

You test the temp sender? Simple test,key on.ground out the orange lead at the harness connection block. Should make the buzzer sound off.

Is this the harness connection block?
panel.jpg

Am I missing an orange lead?
 

pnwboat

Rear Admiral
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Oct 8, 2007
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Re: My Force 150 failed me (again)

Yes. It's the fourth terminal up from the bottom, or fifth one down from the top. Looks to be Brown or Tan in your case (My manual say it's either Orange or Tan). Brown or Tan wire coming in from the left should eventually go to your overheat buzzer. Wire that goes off to the right should go to the overheat sensor on the head. Like Jerry said, ground that terminal with the ignition key on and the overheat buzzer should go off if you've got one.
 

johnbottsr

Petty Officer 2nd Class
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Oct 6, 2012
Messages
104
Re: My Force 150 failed me (again)

I did try that one but my jumper was a bit sketchy.
I'll give it another shot tomorrow.

Would it be typical to just not have a buzzer?

Is the overheat sensor what my manual calls the thermoswitch?
 

jerryjerry05

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May 7, 2008
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18,072
Re: My Force 150 failed me (again)

No, every motor would have a buzzer,unless someone re-installed the motor and didn't hook one up.
Yes it's the thermos switch.The thermo switch is also called the sending unit. It should be on the powerhead.Tan or orange wire.
Between the top 2 plug/cylinders.
Any piece of wire will help ground the system.
Key on,ground out the lead from the head on any exposed metal, carb or starter bolt etc.
If that doesn't make a noise??? Then check under the dash for a round black thingy,again with a tan or orange lead.
Find it? Key off supply power to it and make sure it works at all???
Most Forces have a wiring diagram or a decal of the connections somewhere on the block.

Yes it was very nice of PNWboat to offer the loan.
I always tell anyone who asks to get/loan tools. There will be a $150 NON-refundable deposit:)
Or just bring it around and I'll help.
 

johnbottsr

Petty Officer 2nd Class
Joined
Oct 6, 2012
Messages
104
Re: My Force 150 failed me (again)

Well I managed to borrow a nice compression tester from a guy at work and was all set to go check things out, but I watched Frank's video in the FAQs and he warns to never crank the motor without the spark plugs being grounded or you could damage the ignition.
So, what do you guys use to ground the plug wires?

Also, would jumping from the battery to the starter be the way to do this solo?
It is too far to the ignition switch to keep an eye on the gauge and crank.
 
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