Perkins 4-154 Wiring Diagram

[SV Demeter]

Yes more conversations with myself here but I think I am going to end up purchasing from TA Diesels a new instrument panel and wiring harness.

TAD for marine instrument panels, marine gauges, marine senders, marine alarm switches, marine tachometers


I also found over the weekend that the additional starter solenoid was completely unneccesary and removed it along with about 70' of useless wire. Why is it that when PO's decide to make a change or add equipment that they leave all the old wire? And who decides that tapping into the cabin light circuit is the best way to get and additional 12v source for the engine instrument panel? Yes we will be rewiring most of this boat

Had the OEM alternator redone in town and will be reinstalling it this week so the engine battery will have its own independant charging source.

My remaining question is related to Glow Plugs. The new instrument panel will have a momentary switch for the glow plugs. I am thinking I will use a relay down on the engine to take 12v+ from the engine start battery(via the output terminal on the alt). This way I am only using the momentary switch at the panel to activate the relay instead of bringing power up to the panel switch and back to the glow plugs. Question is in sizing the relay and wires. How much current should I anticipate the glow plugs requiring? The wire currently connected to the glow plugs is #10. The wire from the + terminal on the starter that goes over to the alternator is #8. I was thinking I would use a short (maybe 6") run of #10 from the alt output to the relay then more #10 to the glow plugs ( maybe 18"). Keep in mind this alternator is only charging the start battery. House bank has its own 100amp balmar and 0/2 output wire. Guessing the other two poles on the relay would get #14 wire for ground and for + from the momentary switch.

[dadidoc]

I have the same issue. Mine is a Japan built engine with glow plugs that no-one seems to have ever used. I think my boat was at one time repowered and an engine with the J in the serial number ended up in my boat. Would REALLY like to use these plugs, but am confused with the empty spade connectors.Identifying my Engine

[SV Demeter]

I ended up getting rid of all of it. I bought a standard solenoid for the glow plugs and wired up the new panel from TAD with its new harness. All is well. FWIW your engine looks identical to mine from the two photos on your link. I would say its a 4-154.

[chala]

Quick guess here.
The diode may be a free wheeling diode to minimise surge from inductive load.
One of the solenoid is to prevent circulating current and disconnect the wiring from ground.
Glow plug around 6.5A at 10.5V.
Glow plug relay to minimise voltage drop.
Normally glow plug relay will be ON, on glow and on start.
Normally Perkins does not include unnecessary wiring but can have mistake.

[csmithers]

Originally Posted by SV Escape Plan

My remaining question is related to Glow Plugs. The new instrument panel will have a momentary switch for the glow plugs. I am thinking I will use a relay down on the engine to take 12v+ from the engine start battery(via the output terminal on the alt).

Okay, I'm not a mechanic. But I'm in the process of buying a boat with glow plugs that are not operating properly. The mechanic told me that he's not sure about my engine (Westberke 4-91, equivalent to a Perkins 4-91 I believe), but usually glow plugs require LESS than 12 volts. This is what the solenoid is for, to reduce the voltage. If you put 12 volts into your glow plugs and they're not designed for it, you may be killing them instantly (or slowly too). You really want to find out the required voltage first before you wire them up. Glow plugs aren't hugely expensive but they're enough especially with 4 cylinders to put a $100 or more hole in your pocket.

[chala]

Originally Posted by csmithers

This is what the solenoid is for, to reduce the voltage.

How does it do that?
Normally a glow plug indicator or the operator manual let you know for how long the glow plug should be operated.

Originally Posted by SV Escape Plan

My remaining question is related to Glow Plugs. The new instrument panel will have a momentary switch for the glow plugs. I am thinking I will use a relay down on the engine to take 12v+ from the engine start battery(via the output terminal on the alt). This way I am only using the momentary switch at the panel to activate the relay instead of bringing power up to the panel switch and back to the glow plugs. Question is in sizing the relay and wires. How much current should I anticipate the glow plugs requiring? The wire currently connected to the glow plugs is #10. The wire from the + terminal on the starter that goes over to the alternator is #8. I was thinking I would use a short (maybe 6") run of #10 from the alt output to the relay then more #10 to the glow plugs ( maybe 18"). Keep in mind this alternator is only charging the start battery. House bank has its own 100amp balmar and 0/2 output wire. Guessing the other two poles on the relay would get #14 wire for ground and for + from the momentary switch.

Keep the wire short, why not direct from the + terminal on the starter.

[csmithers]

Originally Posted by chala

How does it do that?
Normally a glow plug indicator or the operator manual let you know for how long the glow plug should be operated.


Keep the wire short, why not direct from the + terminal on the starter.

Don't know how it's supposed to work, just relaying what the mechanic I was talking to was saying. Thought it could be useful since we were talking about much the same thing.

[dbraymer]

Sitting in Golfito, about to try the canal. The high torque starter on the CT-47 4-154 has been hit and miss, so I am putting back in the original starter. Of course I ran again across the mysterious black box which appears to be related to the glow plugs.

I am a retired electrical engineer/ computer field engineer/systems programmer, supposed to be a smart guy, and the English wiring things is a bane to the world.

This thread, with its pictures and comments, has done more good than all of perkins documentation.

TA diesels is great, but perkins put the 4-154 into the field with 20 different wiring versions.

With my back ground, I am not afraid to redo things, and I am convinced that a momentary switch flipping a solenoid to run the glow plugs is the way to go. and pitch the mystery box.

My plan when I get the time, is to use the wiring diagram that you dug up, and simplify/correct it and add the new home made glow plug circuit, and stick it into my workshop manual. Thanks to all the smart and sharing guys on this forum who are willing to help.

I am not a robot.... I am not a robot... I am not a robot...