95' Merc 4.3 LX IV Alpha One Starting/Wiring Issue

Leedanger

Petty Officer 1st Class
Joined
May 29, 2011
Messages
323
Have a Lake Powell trip planned in a day so I hope someone can help me with this. I got a 95' Chaparral with a Mercruiser V6 4.3L LX Alpha One IV Serial # 0F3636*** Manual #18.

It cranks but won't start, occasionally I get a backfire. There are a few wires that are not connected in the engine compartment that I can't seem to track where they go. Towards the stern I have a tan wire with a wire boot on it. It looks like it came off of what looks like a temp sender unit in the back (it's kind of mushroom shaped like what's on the front of the 140), if I pop it on to that the warning buzzer will sound consistently when I turn the key. I have a purple wire on the starboard side down by the starter thats not hooked up. I hooked a multimeter to it and it does not have any volts, I believe it runs over to the fuel pump because I can't ever hear the fuel pump turn on. To test my theory I unplugged the fuel pump and ran power to it separately and it will turn on, but the engine still won't start. Finally I have a purple and black wire, up by the carb and the purple does have 12.3v going to it. I'm assuming it's my + to the fuel pump but I haven't tried hooking it up, I'd like to get it to start first.

Lastly can someone verify the order of the cylinders so I can make sure I am reading it right? Starboard side starting towards the stern I have it is 1,3,6 and on the port side again starting at the stern 2,4,6

Stern
1 2
Starboard 3 4 Port
5 6
Bow

Thanks!
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 95' Merc 4.3 LX IV Alpha One Starting/Wiring Issue

The purple wire, and the black wire may go to the automatic choke. It could also be an extra black wire in the harness. Also look at the purple wire again and see if it has a white stripe on it,
The tan wire is for the temp sender, but should be on the front of the engine.
Not sure about your discription of front and back, so put these pictures together so we are speaking the same language.
You also need to find #1 TDC of the compression stroke to find out where #1 spark plug wire goes on the distributor in case the distributor was installed at a different location.
Find it like this. http://forums.iboats.com/showthread.php?t=427081



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Leedanger

Petty Officer 1st Class
Joined
May 29, 2011
Messages
323
Re: 95' Merc 4.3 LX IV Alpha One Starting/Wiring Issue

Thanks Don...

Ya I read that cylinder order totally screwy, it was all types of backwards. No wonder it didn't want to start. As per the wires with missing homes. The tan one stern side of carb actually had a blue stripe down it I didn't see at first glance and I still don't have it hooked up. As for the purple, there was no white stripe but there was a yellow on one of them. I agree with you about the electric choke...if this had one. What I ended up doing though was using that purple that was hot with key on and tying it into the purple with yellow stripe (which was for the fuel pump) and it fired up.

I fired up right now I have the cylinders wired backwards though....I have the # one cylinder as the starboard/bow side of the motor vs as you say the port/bow side. This would explain the full second hesitation when I start it.
 
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