1995 6 cyl. 90 hp. Mercury outboard not started for years

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b9303

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Need advice and expertise on how to proceed. Have a boat that hasn't been in the water for at least 3 years. Put in a new battery and fresh gas, hose,and fuel line. Pulled and wiped off plugs, put a squirt of Marvel Mystery Oil in each cyl. and pulled the rope. Tried to start motor,gas
was coming out of the top carb,stuck float ? Pulled several plugs and saw no spark, does this
motor have points ? Going to use spark tester today, and also check compression. Put out an
ad for repair manual, what else should i be doing ? Thanks for any info, Found out the motor is 1986.
 
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Maxz695

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

The needles may not be seating. there should be no gas in the carb throats when priming it. Is this engine hooked up to a boat? Is the harness connected to a throttle? Is the engine on a stand? reasons for no spark can be many things but more info on how your trying to start it would be of help.
 
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carholme

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

What is the s/n of your engine? If it is a 6 cyl. 90hp, 1995 does not sound right. Do you mean 1985?

Gerry
 
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b9303

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

s/n OA98534 Not sure about the 3, hard to decipher. Thanks for reply, Joe.
 
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b9303

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Motor is on boat, on trailer, using "muffs" on hose.Starting from console with harness.Was trying to check for spark by grounding a non-fouling plug to engine. Now have a proper spark tester and a compression guage, will re-test tomorrow. Found a troubleshooting manual online free, reading up on problems and fixes. Thanks for reply, Joe.
 
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b9303

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Thank you for info, will keep all advised. Joe
 
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Maxz695

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Disconnect the keyswitch kill wire from the switchbox if you have one I believe it is black and yellow striped. This will eliminate all grounds that would cut out the switchbox or points if its a distributor model engine. Then retest for spark. If you have an overboard layard kill switch you might want to try diisconnecting it and try again. The plastic keys sometimes gets worn and it doesn,t open the circut therefore no fire.
 
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b9303

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Thanks, let you know tomorrow pm. Joe
 
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b9303

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Checked compression, 168# +/- within 3# on all 6 cyl. No spark. Pulled kill switch wire off ignition, still ng. I'm told the motor is 1986, does it have points ? power packs ? Still have to clean carbs and new floats, but would like to solve spark problem first. Going to look for exploded parts view.
 
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carholme

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Joe;

The manual you require for your engine is P/N: 90-86134--4

In the interim, here is a condensed version of the Clymer manual to get you started. Download it soonest to your computer as the link is short lived.

Small Engine Repair Reference Center Home

Gerry
 
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b9303

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Thanks Gerry, downloaded and am reading. Joe
 
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Maxz695

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Models 90, 115 and 140 These models are euipped with a solid state, capacitor discharge igniton system consisting of Trigger coils, stator, switchboxes and ignition coils.
 
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b9303

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Thanks, Max,finally got over to the boat, it's in a friend's yard.
Pulled wires off coils and starter , cleaned and re installed. Wire from solenoid to starter was actually loose and wiggly ! Ran continuity and resistance tests on coils, not real sure if i'm doing it right. Set tester on 200 ohms,touched red and black terminals, reading was 00.4. My info says it is supposed to be 0.04.When i tried
black terminal and coil tower there was no reading, was i supposed to use a different scale ? Only tried two coils,need some help how to proceed .
 
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Maxz695

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Ok from what i,m reading you tightend the starter positive wire and the engine is now turning over ok Correct? Now you are moving on to checking the coils with dificulty. If the engine is now turning over and you still have No spark The toruble shooting section on the manual for thr switchbox and stator should be in there including all meter reading info etc. Can you post a picture of the electrical system switbox wiring? It can be used to decribe parts and wiring. Thanks. I would first start with the stator test. This would be the most likely culprit for absolutely no spark. But it is not the ony thing that can be the cause of No spark. Switbox Main capacitor blew. Something grounding out the kill wire on the switchbox. Key Ing. Tily Kill switch and more so test the main things and I would remove the black yellow wire off the switchbox to eliminate and kill grounds as the cause. View attachment 179509 This is and edited edited pic of my 70 so just use the Key kill wire info remove and test for spark. It also shows the tilt kill switch that shuts the engine down when tilted up. There will be no spark if the engine is not in the down position.
 
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b9303

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Thanks again Max. Your pic shows me where i should take the kill wire loose. Not knowing, i had just pulled it off the ignition switch. The motor is in the upright position on the boat, so i don't think i have to check the tilt switch. Will try to get pics later today. The stator test says to hookup a known good one, i'll have to try to find one in town. (Bradenton, Fl).
 
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Maxz695

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

Your in bradenton so am I I have one from my 70 HP that might work on at least one awitchbox not sure. Where in Bradenton? I,m west Bradenton in Bayshore Gardens. I would have to find out if you have a 6 pole switchbox or a double 3 pole switchbox. and the stator amp. It should be in the manual. I have a 9 amp startor. Blue Red and two yellow wires with a black ground
 
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Maxz695

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Re: 1995 6 cyl. 90 hp. Mercury outboard not started for years

I made a trip to the poster and we got it figured out. A few things needed attention. Key switch issues and the overboard kill switch key had worn down not allowing the switch to make contact. Although the carbs where spweing fuel due to sitting. We did hook up the muffs and turned it over enough to just get her to show it would fire and run. He is going to clean up the carbs with berrimans and he should be good to go. Good luck with it Joe. Scincerely Maz695 Nice engine!!!!:rockon:
 
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