Mercruiser 496 proplem
#82
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From: Sweden
Between +12v and ground = 29-31 Kohm
Between +12v and sparkplug output = 10-11 Mohm

#83
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From: Sweden
The engine heads have been overhauled.
Time to start up the engine again and hope it will run fine this time.
When I turn the key on, a relay is clicking constantly. The relay on top of the engine at the ECU. This one:

Why is it clicking?
It happened after this:
I tried to start it up for a first try before the relay startet to click. The engine turned over a couple of times letting fuel pump forward in the system.
Stoped the engine, and cranked it again, this time it only cranked maybe half a turn and I heard a electrical spark or something and the engine stoped cranking.. it smelled electrical smoke so I turned all safety switches off and took of the cables from the battery.
Went all over the electrical system and found two nuts where loose to the slave relay to the starter, strange because I havent touched them. (Yellow cable with red stripe, and red cable with blue/or purple stripe).
Tightened it up and after this the relay is clicking.. have something happened to the relay or maybe something else?

12+ v on starter key and on the main fuse on the engine (the red push button). The engine fuel pump is starting when I turn the key on But it is this relay clicking sound. Dont want to try to start the engine before I have answears what it can be/or what happened.
Time to start up the engine again and hope it will run fine this time.
When I turn the key on, a relay is clicking constantly. The relay on top of the engine at the ECU. This one:

Why is it clicking?
It happened after this:
I tried to start it up for a first try before the relay startet to click. The engine turned over a couple of times letting fuel pump forward in the system.
Stoped the engine, and cranked it again, this time it only cranked maybe half a turn and I heard a electrical spark or something and the engine stoped cranking.. it smelled electrical smoke so I turned all safety switches off and took of the cables from the battery.
Went all over the electrical system and found two nuts where loose to the slave relay to the starter, strange because I havent touched them. (Yellow cable with red stripe, and red cable with blue/or purple stripe).
Tightened it up and after this the relay is clicking.. have something happened to the relay or maybe something else?

12+ v on starter key and on the main fuse on the engine (the red push button). The engine fuel pump is starting when I turn the key on But it is this relay clicking sound. Dont want to try to start the engine before I have answears what it can be/or what happened.
Last edited by JohanSweden; 03-31-2021 at 03:39 AM.
#85
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From: Sweden
It says that the relay is ”throttle shiftcable relay”, I dont have the throttle linkage on the throttle body.. can it cause this clicking to happen?
#86
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From: Portland OR
I really don't know but I'd have everything hooked up and adjusted like it should be to eliminate any possibilities. You smelled something burn so hopefully you can find it. I've found where the burning happened in the past by sniffing around, usually the smell stays right on the part that smoked.
Here is the fuse I was talking about. Your engine won't crank when this is blown.

Here is the fuse I was talking about. Your engine won't crank when this is blown.

#87
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From: Sweden
I really don't know but I'd have everything hooked up and adjusted like it should be to eliminate any possibilities. You smelled something burn so hopefully you can find it. I've found where the burning happened in the past by sniffing around, usually the smell stays right on the part that smoked.
Here is the fuse I was talking about. Your engine won't crank when this is blown.

Here is the fuse I was talking about. Your engine won't crank when this is blown.

#88
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From: Sweden
Switched the relay from the other beside this one (it is the same), to see if it was the relay that was bad. But it clicking anyway.
Put the throttle linkage back on the throttle body also, nothing happened. The relay still clicking
Put the throttle linkage back on the throttle body also, nothing happened. The relay still clicking
#90
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Joined: Sep 2019
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From: Sweden
No loose cables anywhere where I can find..
I tried to crank her up. It did fire up.. But on the Smartcraft display it says ”warning” and it still clicking. Didnt hear if it clicked when the engine was turned on.
Dont know the fault code yet.
Gonna try to see if I can find it in the VesselView app.
I tried to crank her up. It did fire up.. But on the Smartcraft display it says ”warning” and it still clicking. Didnt hear if it clicked when the engine was turned on.
Dont know the fault code yet.
Gonna try to see if I can find it in the VesselView app.




