140 mercruiser no spark help!!!!!

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michaeli84

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i have no spark i tried hooking the battery straight to the coil and still nothing what should i do the coil should still be good i just bought the motor and dropped it in yesterday this happened when i tried to start it out of the boat would the wire harness not being plugged in cause this or no what should i do i want to start this thing so i can listen to it. thanx
 
Bt Doctur

Bt Doctur

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Re: 140 mercruiser no spark help!!!!!

Is the battery hooked up to the motor?
The motor can be run on a pallet by hot wiring.does the starter turn the motor over?
Are the points clean and adjusted properly
plug firing order correct
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

the motor is in the boat not hooked up to anything right now i checked the points and they were clean this motor was rebuilt and only ran for less than an hour i just dont know why thir is no spark.
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

yes the starter turns the motor and theirs good compression and its getting fuel
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

would the wire harnees have something to do with this
 
JustJason

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Re: 140 mercruiser no spark help!!!!!

Yes the harness could have something to do with it. Go to the "Adults only" section. In there you'll find manuals for troubleshooting your engine.
 
Don S

Don S

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Re: 140 mercruiser no spark help!!!!!

May just need a new set of points.

i tried hooking the battery straight to the coil and still nothing
Click to expand...

Did you hook the jumper wire to the + or - terminal on the coil?
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

well i replced the points, condenser,rotor, cleaned all the spark plugs and even tried a different coil from my previous motor that siezed. Still no spark i dont have a clue on what to do next. i have 2 of everything for this motor cause i was going to try to rebuild the original motor. I thought the coil was bad but whats the chance of 2 coils being bad i think pretty slim.So if their is spmething i am leaving out or missing i would appreciate the info. I cant wait to get it started and go do some fishing. thanx
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

well i replced the points, condenser,rotor, cleaned all the spark plugs and even tried a different coil from my previous motor that siezed. Still no spark i dont have a clue on what to do next. i have 2 of everything for this motor cause i was going to try to rebuild the original motor. I thought the coil was bad but whats the chance of 2 coils being bad i think pretty slim.So if their is spmething i am leaving out or missing i would appreciate the info. I cant wait to get it started and go do some fishing. thanx
 
APPALOOSA2

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Re: 140 mercruiser no spark help!!!!!

I would start by tracing back all wires on the engine and check your ground wires . If all checks out I would look at the ignition switch.
 
ken_23434

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Re: 140 mercruiser no spark help!!!!!

There is the interrupt switch that could be causing the problem. If I understand it correctly, it cuts out the spark when you shift from neutral into fwd or rev to help the outdrive engage. If that switch is not in the correct position, it might be preventing your spark.

There will be a better explanation in the service manual. Just pointing you to another possible area of concern.
 
bruceb58

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Re: 140 mercruiser no spark help!!!!!

Measure that you have 12V at the positive side of the coil.

Take all of the wires off the negative side of the coil and only put on the one that goes to the distributor. If that works, add the other wires(tach...esa) to see what may be causing a problem. Also, the wire that goes from the negative side of the coil goes to one side of the points. Make sure you didn't accidentally ground that side. Are you using a dwell meter? You can check the dwell by just cranking the engine. If that doesn't look right, you grounded something accidentally.
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

thanks guys i took all the tape off the harness and traced all the wires they were all in the right spots according to my manual that came with the boat. I have not checked any switches or anything cause i dont really know where they are or much about the and i dont want to mess anything up. However i can look in the manual to see and maybe thats the answer to my question. thak you very much for your time and knowledge guys.
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

i never hooked the ground from the block to the actual boat up but a friend said that dont matter its the ground by the water drain plug that attaches to the rear mount ive held it in place and cranked just never hooked it up do you think that could be it.
 
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xltier

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Re: 140 mercruiser no spark help!!!!!

michaeli84 said:
i never hooked the ground from the block to the actual boat up but a friend said that dont matter its the ground by the water drain plug that attaches to the rear mount ive held it in place and cranked just never hooked it up do you think that could be it.
Click to expand...

if your motor wasnt grounded it wouldnt turn over.try just a power wire to + side of coil.then the distributor wire to -.nothing else.crank the engine and check for spark.if not then its either the points,condenser,rotor.cap.coil wire.make sure the distrributor is turning also.
 
bruceb58

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Re: 140 mercruiser no spark help!!!!!

michaeli84 said:
i never hooked the ground from the block to the actual boat up but a friend said that dont matter its the ground by the water drain plug that attaches to the rear mount ive held it in place and cranked just never hooked it up do you think that could be it.
Click to expand...
The fact that you asked a question like that makes me believe you should probably get someone to help you.
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

bruceb58 said:
The fact that you asked a question like that makes me believe you should probably get someone to help you.
Click to expand...

I know it sounded pretty dumb its the ground stud on the flywheel housing to the inner transom plate. Someone said check the grounds just wondering if that would have been it. Sometimes ti is the stupidest things ya know. Im a union carpenter 10 years definately not a mechanic but it sure does interest me. Thats why i stripped my old engine and im rebuilding it with experienced friends. The funny thing is they help me do the old motor but when i get a new one and im a c**t hair away from getting it to run they suddenly dont have the time but thats why im trying to tackle this myself i know how it is to be busy thanks for the comment dude!
 
bruceb58

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Re: 140 mercruiser no spark help!!!!!

Well...if you understood what I was saying in my post before, try those things.

Do you know how to use a multimeter? Do you own a multimeter? How did you set the points to the proper dwell? You haven't indicated how you have done any of those things yet you are off looking at the engine connector. You can do a lot of simple tests with a multimeter and a dwell meter before you go off chasing down your engine connector.
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

xltier said:
if your motor wasnt grounded it wouldnt turn over.try just a power wire to + side of coil.then the distributor wire to -.nothing else.crank the engine and check for spark.if not then its either the points,condenser,rotor.cap.coil wire.make sure the distrributor is turning also.
Click to expand...

I did run power straight to the + side of the coil and still had the ground on and off still no spark i said earlier that i have another coil also. I swapped them and still the same thing. I just changed the shift interupter switch and cleaned it all up and got all the gunk off of everything in that area. I noticed that the switch is by the shift cables when i put the motor in i just hooked the cables up and didnt adjust anything because it seemed like it was good. Do you think that might have something to do with the switch maybe not working right it dont make sense to me but im not a mechanic so i dont know. Im not gonna start it till the morning because its too late and i dont want to make any noise for the neighbors. thank you for your comment
 
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michaeli84

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Re: 140 mercruiser no spark help!!!!!

bruceb58 said:
Well...if you understood what I was saying in my post before, try those things.

Do you know how to use a multimeter? Do you own a multimeter? How did you set the points to the proper dwell? You haven't indicated how you have done any of those things yet you are off looking at the engine connector. You can do a lot of simple tests with a multimeter and a dwell meter before you go off chasing down your engine connector.
Click to expand...

I set the points with a feeler gauge 0.022 i dont have a dwell meter and yes i tried everything you said still nothing man. I ve been reading through the book to try to find whatever solution possible. the reson why i checked the switch is because i tried everything so i moved on to the next suggestion.
 
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