Westerbeke Preheat Power by Key 'On' Position

[GRM]

I'm a new owner of a 1997 Catalina 380 with a Westerbeke 42B engine. I'm not completely confident of my inspection of the wiring yet, but I wanted to post a question about continuously powering the preheat circuit on the Admiral's Panel.

The Admiral's panel was rebuilt at some point, and the preheat circuit was connected to the key 'on' switch. When the key switch is on, the gauges are powered, the start button is powered, and the preheat seems to be powered.

Even after the engine is started, the key remains in the on position to power the gauges, but if the preheat circuit is still powered, that seems like a potential problem to me. Before I begin retracing all wiring for the circuit, I'm interested in any other similar situations encountered, or any known issues with "always powering" the preheat circuit when the key is in the 'on' position.

 

[Maine Sail]

Glow should only activate when you depress the left black rubber covered momentary switch.. The way it was wired from the factory required glow to be pressed in order to activate the start button for the motor. Someone apparently bypassed that feature...

 

[Head Sail]

the preheat circuit is not hooked to the key switch. When the key switch is on, the gauges are powered, the start button is powered, and the preheat *seems* to be powered.

This doesn't make sense...if the preheat is not hooked to the key switch, how would it *seem* to be powered?

but if the preheat circuit is still powered, that seems like a potential problem to me.

That would be a problem. You would probably burn out your glo plugs and/or discharge your batteries quickly. Glo plugs use substantial power.

 

[GRM]

Thanks, I edited the mistake in my original post. The 'on' position is powering preheat. I believe that unless there is another unseen connection disrupting it, that preheat is powered at all times the key is in the on position, including at engine run time (which is the most common case). I will do some more diagnostics and update the thread.

 

[LakeOntario270]

On my boat the key has 3 positions Off, On, and Preheat. I start the engine by holding the key in the Preheat position with my right hand and push the start button with my left hand. When I let go of the key it will not stay at the Preheat position but move to the Run position like a car key.

 

[Meriachee]

Some of the Catalina panels are wired such that the key turns past "on" to a preheat connection. You turn the key as far as it will go, then a number of seconds later start the engine with the black button, wait a few seconds to ensure all cylinders are firing and then release the key, and the spring in it brings it back to the "run" position.

Are you sure that this is not the scenario?

 

[Head Sail]

I see a voltage drop from 12v down to about 10v when activating glo plugs. If your seeing over 12v with the ignition switch on, your glo plugs probably are not on.

 

[jviss]

Agreed, it the glow plugs are always powered, they will quickly burn out. Don't ask me how I know.... And, they do draw a lot of current, like 6 or 7A each.

The schematic shows the preheat switch in series with the start switch, so preheat must be depressed for starting.

Here's the schematic:

Admirals Panel Schematic P1

• jviss
• Sep 27, 2017

Admirals Panel Schematic P2

• jviss
• Sep 27, 2017

 

[LakeOntario270]

I hear the pitch of my blower drop when the glow plugs are on.
I can start the engine in run mode. Without glow plugs.

 

[jviss]

If you are tracing wires, it could be that you are just making a mistake, or an assumption.

By the way, it seems there were many options in how these engines were wired, so without a very thorough inspection you will never know what you have. For example, you may or may not have a neutral safety switch, a fuel solenoid, and so on. And, as MaineSail points out, someone may have modified the wiring. I plan on modifying mine to not require the glow plug circuit to energize the starter. I will mark up a hard copy of the schematic that's on the boat if I do so.

 

[jviss]

Thanks, I edited the mistake in my original post. The 'on' position is powering preheat. I believe that unless there is another unseen connection disrupting it, that preheat is powered at all times the key is in the on position, including at engine run time (which is the most common case). I will do some more diagnostics and update the thread.

Do you meant the "ON" is providing power to the preheat pushbutton?

 

[jviss]

On my boat the key has 3 positions Off, On, and Preheat. I start the engine by holding the key in the Preheat position with my right hand and push the start button with my left hand. When I let go of the key it will not stay at the Preheat position but move to the Run position like a car key.

The poster has the Admiral panel, which has separate keyswitch, preheat pushbutton, and starter pushbutton.

 

[GRM]

Some of the Catalina panels are wired such that the key turns past "on" to a preheat connection. You turn the key as far as it will go, then a number of seconds later start the engine with the black button, wait a few seconds to ensure all cylinders are firing and then release the key, and the spring in it brings it back to the "run" position.

Are you sure that this is not the scenario?

My key does have another position after ON. Turning it seems to make a repetitive clicking noise from the engine compartment. It's another thing I must investigate. The comments here have been immensely helpful, and I'm eager to follow up on all the ideas and I will post my progress. Thank you.

 

[capta]

My key does have another position after ON. Turning it seems to make a repetitive clicking noise from the engine compartment. It's another thing I must investigate. The comments here have been immensely helpful, and I'm eager to follow up on all the ideas and I will post my progress. Thank you.

Does your engine run? Have you run it for any length of time?
The manual for my Onan states that the glow plugs must not be operated continuously for more than 30 seconds! I can not imagine that your glow plugs have been operating the whole time the engine was running (more than 10 minutes?) without burning out. An audible clicking may be a solenoid for the glow plugs not working correctly.

 

[GRM]

The poster has the Admiral panel, which has separate keyswitch, preheat pushbutton, and starter pushbutton.

That is true, but as I mentioned, the Admiral's panel was rebuilt at some point, and my preheat button is altogether missing from the new panel. I found the lead (labeled preheat) and it seems to be wired to "on" on the keyswitch. I will investigate if it may be, in fact, the position after "on". I didn't realize that the engine would start without preheat (which it would have to, since I've never turned the key that far).

 

[GRM]

Does your engine run? Have you run it for any length of time?

Yes, the engine runs very well, and I have put about 16 hours on it since buying the boat. I'm guessing there is some assumption or missed connection, as another poster mentioned. I will update the thread as I gather information.

 

[capta]

Yes, the engine runs very well, and I have put about 16 hours on it since buying the boat. I'm guessing there is some assumption or missed connection, as another poster mentioned. I will update the thread as I gather information.

Then it is my guess that your glow plugs are not operating while the engine is running. Kubota has a visual indicator that lets one know when the glow plugs are hot, for very little money. I've just picked one up, but haven't gotten around to installing it yet.

 

[Meriachee]

My key does have another position after ON. Turning it seems to make a repetitive clicking noise from the engine compartment. It's another thing I must investigate. The comments here have been immensely helpful, and I'm eager to follow up on all the ideas and I will post my progress. Thank you.

That is exactly the sound that mine makes when the key is in the preheat selection.
There's probably little point in referencing what panel it is or what may have been originally installed, it simply may have been changed. Or then again, not. I can say that mine is original and that is how it works, and from your reply, it would seem that yours is the same. Turning the key all the way clockwise puts it into a spring loaded setting, there is clicking as you suggest, you also see the volt meter reflect a very heavy draw, and if you let go of the key without pressing the start button, the spring rotates it counter clockwise a little bit, the volt meter goes back to something reasonable and the clicking stops?

 

[Head Sail]

I'd hazard a guess the clicking sound is your fuel pump running when your glo plugs are activated.

 

[Davidasailor26]

I'd hazard a guess the clicking sound is your fuel pump running when your glo plugs are activated.

I would also guess the clicking could be a fuel pump. But the pump often runs whenever the ignition is on, you just probably can't hear it over the engine noise. Why the pump would only run when the key is turned passed "on" is another mystery. Maybe someone had the idea to wire it that way to try to help with bleeding the fuel system or something.