89 4.3L No Electrics

[Volphin]

Hi guys,

Just finishing up my repower on my 89 4.3L, Alpha 1, TB4.
I have installed the new engine, aligned the engine and installed the out drive.
Hooked up the electrics and have no power at all. I suspect I have the starter wired wrong.

It is a 4 post starter, Delco Marine. Here is how I have it wired ('noid facing up)

6 o'clock: Nothing except the built in bridge to windings
3 o'clock: Yellow with red stripe
9 o'clock: no connections
12 o'clock: 1) Main battery + lead, 2) orange from ALT, 3) red to multi pin connector, 4) red from trim motor.

I have no blower motor, nor trim actuation.

Battery seems fine.

Do I have this starter wired incorrectly? Am I missing something? (Besides 5 gallons of water I sweat out this afternoon? LOL)

Moral of the story: don't let a buddy disconnect starter until you have at least eyeballed it.

 

[sptjet90Reflexx]

Re: 89 4.3L No Electrics

gimmie a min, ill take a picture of mine.

 

[sptjet90Reflexx]

Re: 89 4.3L No Electrics

Here ya go.. 4.3L 1989 mercruiser.

 

[Volphin]

Re: 89 4.3L No Electrics

I don't get it... Looks like we have them wire up the same... Hmmmm.

 

[sptjet90Reflexx]

Re: 89 4.3L No Electrics

bad ground?

 

[Don S]

Re: 89 4.3L No Electrics

Do you have all the grounds hooked up?

 

[Don S]

Re: 89 4.3L No Electrics

3) red to multi pin connector

Actually, that should go to the 50A circuit breaker on the engine. A red/purple wire comes off the breaker and goes to the round 10 pin connector and on to the helm and the key switch.

Your trim pump wire should go directly to the battery, not the starter.

 

[Volphin]

Re: 89 4.3L No Electrics

Actually, that should go to the 50A circuit breaker on the engine. A red/purple wire comes off the breaker and goes to the round 10 pin connector and on to the helm and the key switch.

Your trim pump wire should go directly to the battery, not the starter.

Thanks Don! I thought the same thing about the trim pump. Something is up though... it won't reach. The wiring to the 50A electrics should be A-OK. I didn't disconnect them and were stowed as an assembly during R&R.

The ground from the batt is attached to the bell housing, and another ground is attached to the starboard motor mount from the main harness that leads to the 50A/Pin connector assy.

Would the trim pump being connected to the starter at the same location as the + cable not act as if it was connected to the battery directly?

 

[sptjet90Reflexx]

Re: 89 4.3L No Electrics

No the trim pump wiring is fine. the only reason you put it right on the battery vs the starter is less resistance through the cable for a more solid connection.

 

[sptjet90Reflexx]

Re: 89 4.3L No Electrics

Here is the real question.. How do you know "the battery seams fine"? what test did you preform? just cause you have 12v at the post does not mean you have any amps behind it to power anything.

 

[Don S]

Re: 89 4.3L No Electrics

No the trim pump wiring is fine. the only reason you put it right on the battery vs the starter is less resistance through the cable for a more solid connection.

No, the trim pump is put directly to the battery to keep from overloading the starter terminal. There is no more resistance from the battery to the starter to the trim pump.
Ever notice how the service manuals and install manuals show the trim hooked directly to the battery ??????

 

[Volphin]

Re: 89 4.3L No Electrics

I was able to do some more testing this morning before work. Looks like the problem is isolated to the trim pump and blower. I have lights, horn and the fuel pump runs. Is there a common ground for these two items?

 

[sptjet90Reflexx]

Re: 89 4.3L No Electrics

they are all grounded to the back of the motor, follow the - cable on the battery. Should be on the back left side if your are looking at your motor from the pully side.

 

[sptjet90Reflexx]

Re: 89 4.3L No Electrics

No, the trim pump is put directly to the battery to keep from overloading the starter terminal. There is no more resistance from the battery to the starter to the trim pump.
Ever notice how the service manuals and install manuals show the trim hooked directly to the battery ??????

How can you overload the starter solenoid terminal? it makes a direct connection to the battery through the + wire from the battery on the same post. No current would travel in the solenoid it would be technically be the same as directly on the battery but with longer wire which means more resistance. Factory my trim pump is connected to the + of the starter solenoid. I assume to make the battery hookups look cleaner.

 

[Volphin]

Re: 89 4.3L No Electrics

How can you overload the starter solenoid terminal? it makes a direct connection to the battery through the + wire from the battery on the same post. No current would travel in the solenoid it would be technically be the same as directly on the battery but with longer wire which means more resistance. Factory my trim pump is connected to the + of the starter solenoid. I assume to make the battery hookups look cleaner.

This routing to the starter may have actually been causing another issue I had on my list. Whenever I would trim up or down, the lights would dim, like it was staining the alt.

 

[Volphin]

Re: 89 4.3L No Electrics

No, the trim pump is put directly to the battery to keep from overloading the starter terminal. There is no more resistance from the battery to the starter to the trim pump.
Ever notice how the service manuals and install manuals show the trim hooked directly to the battery ??????

I'm going to rewire it this way by either replacing the lead to the pump or soldering the same Ga wire to it to lengthen it.
The blower and trim don't ground at a terminal block do they? I think I have a few screws loose on the block that attaches to the shift cable bracket assy... and a black wire coming up from a loom near the coil, but I have yet to trace it to it's source.

 

[Volphin]

Re: 89 4.3L No Electrics

OK. Here's an update. And its ugly. Hats off to sptjet90Reflexx and Don asking about the grounds. I was familiar with the port engine grounds, but upon studying some schematics, I decided to go digging on the starboard side. Yep. I had neatly tucked three ground wires into a loom and shoved them behind the pump assy. :facepalm: So yeah, I'm an idiot. Here it is right on record. The repower has taken so long I guess I forgot I stashed them there. I hooked them up, but the game was called due to darkness. I'll test it tomorrow evening. Once again thanks to all. I do have one other wiring question, but will start a new thread as it is an unrelated sub system.

 

[sptjet90Reflexx]

Re: 89 4.3L No Electrics

post a vid of the first start!

 

[Don S]

Re: 89 4.3L No Electrics

How can you overload the starter solenoid terminal?

When I said overloaded, it was not electrically overloaded, but overloaded with too many different wires/cables going to it.

 

[Volphin]

Re: 89 4.3L No Electrics

post a vid of the first start!

Will do.