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502 mpi burning up coils won’t start
hi guys I just finished redoing my 27 fountain the motor came out this winter to be freshened I re-did my dash with all new gauges and required them due to being plug in. Dropped the motor in hooked it all up and wasn’t getting fuel ignition then noticed the coil was smoking after looking everything over checking grounds I found I didn’t have a grounded from the battery to the block. So I grounded that out put a new coil on and the coil instantly got hot and still wouldn’t start I checked the grounds again and tryed again then the coil blew apart. Any help would be great! |
found I didn’t have a grounded from the battery to the block. In any case, look close at the connections to your starter and battery cables. Do you need to turn the key ON for anything to happen or does it start without any change? |
Originally Posted by AllDodge
(Post 4634644)
I think you smoked your harness and probably need another.
In any case, look close at the connections to your starter and battery cables. Do you need to turn the key ON for anything to happen or does it start without any change? |
Reference pdf page 34 at http://www.boatfix.com/merc/Techbk/96/96HGD4.PDF
th Red wire going into your coil powers it. should be 12V+. One would think this is okay as it is connected to the ECM Fuse (10 Amp) ECM/Ignition/Injector/Knock Sensor Module. Double check though, obviously. Possibly you have a problem with the tach wire which is white going into the coil. it is gray going into your tach. is this attached in correct spot to your tach ? should be the 'sig or sender' post on your tach, Note: don't confuse with the 2 wire harness (grey and pink wire) coming from dist going to coil. But yeh, issue with grey wire here could cause issues too. |
bad tach and or bad/ shorted tach wire
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Originally Posted by BUP
(Post 4634656)
bad tach and or bad/ shorted tach wire
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brand new tach can be wired wrong ? and even being brand new can still have issues. -- added info from my post above ----- grounded tach lead anywhere in boat harness and or engine harness. The harness connections itself.
ALSO and have seen this before wrong connections or accessory wires connected to THE SHOP BULLET CONNECTOR ON THE ENGINE. I would check there FIRST.. Actually seen this more than a couple times. <<<<<< That can melt the coil in due time |
I have a test harness for engine stand running or dyno running I’m going to try that to see if it is the panel side or engine side. |
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