Twin motors not staring start

MFO

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I have a 1994 272 Sailfish with original twin 200hp Yamaha Saltwater 2 stroke engine with low hours. Have been running fine. Motors winterized fogging carburetors and cylinders. Existing spark plugs inspected and put back. Oil reserve filled and oil tanks filled. Batteries removed, stored and charged prior to re-installed. Nuts well righted. No other engine work performed except lower unit on one engine seals replaced. Neither engine will now start. They crank well. Batteries fully charged. Can hear primer working. Kill switch had been disconnected years ago. Wiring looks fine and not in contact with anything. Remaining boat electronics working fine. No spark present. Spark plug wires secure. Local boat yard to busy to help. Looking for solution. Thanks.
 

MFO

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Yes. Out of gear. Tried in both forward and reverse disengaged. My understanding is that the engines won’t crank if in gear
 

seasick

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Since you killed the kill switch, I would look there first at whatever it was that you rewired.
 
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MFO

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Since you killed the kill switch, I would look there first at whatever it was that you rewired.
The switch has had some of the wires detached, thus in the open position. Has been this way for about 15 years with no problems. Looks fine. Wires isolated from each other. Thanks for the thought though. Kill switch seems like the obvious cause so I checked this carefully initially. Wish it was the problem.
 

seasick

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Neutral safety switch would do it also but generally if you try to start and not in neutral the alarm would sound (assuming the alarm works).

Also recheck the battery connections. You may have missed a black jumper wire of the accessory ground wire connection when the batteries were reinstalled

( I'm not sure I believe what I said last......).
The juice for the motor comes from the motor through the harness to the ignition switch and then back to the motor. I assume you can tilt the motor wit the switch and if so the motor has juice.
 
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SkunkBoat

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you say "no spark present". Is that an assumption or you checked spark on both engines?

There is fuel in the motor filters?

Try starting fluid?

Carbs could be dry.
 
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seasick

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I assume this is an injected motor. Is that correct?
The question about fuel in the 'carbs' or the motor in general is a good one.
After tring to start with no success, pull a spark plug or two and see if the tip is wet or dry. If wet, you have fuel
 

MFO

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you say "no spark present". Is that an assumption or you checked spark on both engines?

There is fuel in the motor filters?

Try starting fluid?

Carbs could be dry.
Checked spark on one engine only. Changed gas filters for both engines with gas in both. Primers appear to be working and scent of gas can be smelt after repeated attempts to start engines.
 

MFO

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I assume this is an injected motor. Is that correct?
The question about fuel in the 'carbs' or the motor in general is a good one.
After tring to start with no success, pull a spark plug or two and see if the tip is wet or dry. If wet, you have fuel
These are carburetor two stoke engines. As I can hear the primers working and there is a scent of gas and the fuel filters were full of fuel I’m assuming the motors are receiving gas. Thanks for the suggestion. Never experienced this problem in 25 years
 

MFO

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Neutral safety switch would do it also but generally if you try to start and not in neutral the alarm would sound (assuming the alarm works).

Also recheck the battery connections. You may have missed a black jumper wire of the accessory ground wire connection when the batteries were reinstalled

( I'm not sure I believe what I said last......).
The juice for the motor comes from the motor through the harness to the ignition switch and then back to the motor. I assume you can tilt the motor wit the switch and if so the motor has juice.
I have checked the wiring and don’t see any loose wires. The motors do tilt normally, as well as crank.
 
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seasick

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Try a little spray of starting fluid. You can also use brake clean. Spray into the intake manifold and see if the motor fires up. I it does, it means you have a fuel delivery issue or fuel condition issue.
 
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MFO

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Try a little spray of starting fluid. You can also use brake clean. Spray into the intake manifold and see if the motor fires up. I it does, it means you have a fuel delivery issue or fuel condition issue.
I will give it a try. Thanks again for your advice.
 

SkunkBoat

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I have no experience with 94 carbeurated Yammies and their cabling.
The run down

Both don't start.
Both crank and tilt.
Both smell gas.
Appears neither has spark.

Two keys or one?
Kill switch "disabled".

I'm thinking the ON switch is not ON (if its one key....)
or the Kill is killing.
Head scratcher....

Or both motors need a new stator....

Need to troubleshoot spark some more....


20 years ago I had experience with a 91 Merc carbed 150. It would routinely just refuse to start for 30 minutes when I wanted to catch the first light bite. Then the sun came up and it cranked right up like nothing was wrong.
Solution was New Suzuki 4 stroke, injected 14O.
 
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enfish

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I'm with SkunkBoat and glacierbaze on this. The biggest clue so far is that both motors acting the same, therefore problem is likely something common to both, and electrical makes more sense than fuel in this scenario... that leads me to something like the kill switch circuit which would kill the spark. Though you should get an alarm, assuming the alarm is still connected. I know you said it's been bypassed and the wiring looks good, but that's where I would go to second right after confirming all the cables to the batteries got reconnected properly. Next would be ignition switch circuit. I'm assuming the plugs are likely not fouled by the fogging oil since you said you pulled and inspected.
 

enfish

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20 years ago I had experience with a 91 Merc carbed 150. It would routinely just refuse to start for 30 minutes when I wanted to catch the first light bite. Then the sun came up and it cranked right up like nothing was wrong.
Solution was New Suzuki 4 stroke, injected 14O.
I had a boat and a truck with that problem... both small block Chevy engines. Problem in both of them was a bad distributor cap that was letting moisture get inside the distributor. Once the sun came up and it warmed up, the moisture evaporated and the motors would start up fine. The band-aid solution was to pop the distributor cap off and wipe it out with a paper towel until I got a new cap.
 

MFO

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I have no experience with 94 carbeurated Yammies and their cabling.
The run down

Both don't start.
Both crank and tilt.
Both smell gas.
Appears neither has spark.

Two keys or one?
Kill switch "disabled".

I'm thinking the ON switch is not ON (if its one key....)
or the Kill is killing.
Head scratcher....

Or both motors need a new stator....

Need to troubleshoot spark some more....


20 years ago I had experience with a 91 Merc carbed 150. It would routinely just refuse to start for 30 minutes when I wanted to catch the first light bite. Then the sun came up and it cranked right up like nothing was wrong.
Solution was New Suzuki 4 stroke, injected 14O.
 

Fishtales

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2 motors same thing. I'm guessing either fuel or spark. Gotta recheck any rewiring you did. Get a mechanic if you can't solve it quickly.