Engine Electrical Connection Issues

[britinusa]

Ok, decision made.

I'm going to build and install a complete Control Panel to Engine harness.

I'll be adding a new solenoid (thanks Ken) and a -ve Bus Bar in the engine bay.

All new wiring including the control panel and new wires to all of the engine services.

Why? Because I found so many skinny wires, bad crimps, poor and multiple butt connectors and Wire nuts and ... the list goes on.
When I finish this, we'll have a top notch Engine Electrical Harness that will make future servicing easier and more reliable.

This is gonna be Uge! I can build really big harnesses and I'll get others to pay for it! We'll make our boat great again.


(sic)

it will be pretty cool!

just so that you know where we're starting from, here's a link to a google photo album of pics that I took of the existing harness (not sure that's the correct term for this bunch of wires)....
\https://goo.gl/photos/G55EJjY7yCmdVRD8A

Paul

[Jon W]

Looks like mine did when I started my harness upgrade, except my panel tray doesn't have the back on it like yours. Any wires fall out of their crimp when you removed the panel?

[britinusa]

Jon, no wires fell out of their crimps- surprisingly!

At the boat this morning getting my eyes on all of the wires going to the engine devices.

I was going to install a -ve Bus Bar in the Engine bay and connect the Starter -ve, Alt -ve and Battery -ve to that, however this morning I found that the -ve from the Starter and the -ve from the Alternator both run independently back to the -ve Battery bus bar that is on the aft face of the battery bay bulkhead (ie. in galley adjacent to the hot water tank)

And they are both 1/0AWG cables.

However, there are 5 independent ground wires on the engine, not sure where they all go (they're all black and range from #10awg and smaller.

So I'm considering installing the -ve Bus Bar in the Engine bay, and connecting it to the Alt -ve and moving all of the ground connections from the engine (there's 5 of them) to the new bus bar and also connecting it to the engine case.

Regarding installing a jumper between the starter and the alternator.
Currently there is a 1/0awg cable from the alternator to appears to go to the Battery bay, but it goes under the cabin sole and I could not see if it went to the Battery selector switch (above the nav table) or to the Battery bay.
There is also a smaller, probably #4awg or #6awg cable from the stater to the Engine Master Power Switch which is also above the Nav table.
From there it goes to the Starter battery or to the house batteries if the 0ff/1/both/2 switch is on both.

IMHO I don't need to put a jumper cable (#1awg) from the Alternator +ve to the Starter +ve.

I have not laid my eyes on the Blower motor yet, can't see it from underneath the aft berth, I'm guessing it's down in the aft locker somewhere, anyone seen it 

Hopefully the new diagram will be complete this afternoon and I'll post it here.

Paul

[KWKloeber]

Paul,

Potential negatives.

Harness - 10 awg
Fuel level sender
Fuel pump
Fuel tank?
Deck fuel fill?


Note that bonding wires (eg, fuel filler) should be green.

[britinusa]

Panel Feature	Color	AWG	Connect To:
+ve Supply	Red	#8	Starter +ve Post
-ve Return	Black	#8	Engine Bay -ve Bus Bar
Starter Button	Yellow	#10	Starter Solenoid S Post
Glow Plug Switch	Gray	#10	Glow Plug #1 Terminal
Blower Switch	Brown	#14	Blower Motor
Oil Pressure Alarm	Lite Blue	#16	Oil Pressure Switch
High Temp Alarm	Tan	#16	High Temp Switch
Temp Gauge	Tan	#16	Engine Temp Sensor
Tachometer	Gray	#14	Alternator (???)
Fuel Gauge	Pink	#16	Fuel Tank Sensor
Ignition	Purple	#14	Fuel Pump

Engine Bay 8 terminal -ve (ground) Bus Bar
a) Harness to Control Panel -ve
b) Engine ground ( by flywheel )
c) -ve Return for Fuel Level Sender
d) -ve Return for Fuel Pump
e) Ground for Fuel Tank
f) Ground for Deck fuel fill
g) to Starter -ve

Some of these items can be #16 AWG, not sure which!

Update: Thanks Ken, I have updated my list with the sizes.


Paul

[Ron Hill]

Guys : Don't take Pauls' color coding as Gospel. 

Over the years most of us have found that Bristol Marine did it one way and Seaward did it another way. 

When the Catalina factory changed from Bristol to Seaward as supplier (1989/90?) the factory would find some of the old Bristol harnesses and then in stall them - Frank throws NOTHING away.

A thought

[britinusa]

FYI I got the color codes from Defender

https://www.defender.com/pdf/abyc-wire-color-chart.pdf

Paul

[Jon W]

On my boat the blower motor is under the coaming on the port side near of the engine control panel. Without a back on my engine panel tray I could see it. Since your panel tray has a back, you made need to climb into the aft lazarette to see it.

The port and starboard ventilation hoses run from aft of the engine compartment to the exit vents on each side of the cockpit. The port side connects to the blower fan, the starboard side hose only connects to the vent exit. I'm not sure what benefit the starboard hose provides.

[britinusa]

I had always thought that the port side was the 'outlet' and the stbd side was the 'inlet'

Pretty sure that on Eximius, the stbd hose from just sits in the space under the aft berth.

Paul

[britinusa]

Update, using my endoscope, I was able to find the Alternator Model. It's a Balmar 91 75 - 75Amp 14v alternator.

I also measured the wire lengths.
Most harness wires need to be 18' long (that gives a bit of slack at each end and allows for the panel to be pulled from the housing.

The Blower +ve need only be 2' as I'm going to butt joint that to the existing motor wire.

The Fuel Pump +ve is 23' and the Fuel Sender is 26'

when I install them, I can trim off any excess, but rather that than butt joint a wire extension.

Paul

[Jon W]

If you're adding a negative busbar in the engine compartment why not terminate the fuel gauge negative there? A much shorter run.

[KWKloeber]

If you're adding a negative busbar in the engine compartment why not terminate the fuel gauge negative there? A much shorter run.

Paul is planning on that (below.)
You're referring to the level sender negative, correct?  Not the gauge negative (which is grounded at the panel)?

Engine Bay 8 terminal -ve (ground) Bus Bar
a) Harness to Control Panel -ve
b) Engine ground ( by flywheel ) (will be moved to starter bolt)
c) -ve Return for Fuel Level Sender
d) -ve Return for Fuel Pump
e) Ground for Fuel Tank
f) Ground for Deck fuel fill
g) to Starter -ve

[Jon W]

Hard to tell the +ve from the -ve on my phone. Saw 23 and 26 feet and thought they were -ve.

[britinusa]

Since then, further discussion with Ken, and so the +ve for the Fuel Pump is going to be a branch off of Alt Excite post which is supplied from the Ignition Switch.

And the -ve's for the fuel pump and the fuel sender / tank ground will both be going to the new -ve bus bar that will be mounted on the outside of the port engine stringer. (I should be able to access the bus bar from inside the head via the engine access door.)

Paul

[KWKloeber]

Since then, further discussion with Ken, and so the +ve for the Fuel Pump is going to be a branch off of Alt Excite post which is supplied from the Ignition Switch.

And the -ve's for the fuel pump and the fuel sender / tank ground will both be going to the new -ve bus bar that will be mounted on the outside of the port engine stringer. (I should be able to access the bus bar from inside the head via the engine access door.)

Paul

That's one option for the pump. 
Or, if the harness "pases near" the pump, I'd probably take the pump feed right off the excite wire (rather than running it back from the alternator field excite post.)