False high temp readings and engine harness plug

[KWKloeber]

[EDITED]

OHHHH,  D'oh. 
An extra cylinder certainly makes more sense. 
It was a C30 w/ 3 cyls that read 30-ish, so 40-ish makes sense now.

I did one for a C30-er (3-cyl) - I like the socket for a standard 4001 headlight relay,  with a standard 40-amp continuous-duty headlight relay.  I used 10-ga wiring for the power leads (16? or 14? for the relay trigger.)  I couldn't find exactly what I wanted so just ordered in the socket, terminals (open barrel crimp type) and made it up.  I also like that a socket meant to be hard-mounted, the relay is simply a pop-out/pop-in, easy to replace with a spare.  Hella makes 50-amp relay for the 4001 socket configuration.

There's stuff on the wiki 'bout using 8-ga for GP power, which I think is crazily unnecessary since 10-ga is good for 50 amp in the engine compartment and you're talking only a couple of feet (v loss).


something like this looks promising but the relay (not socket) is hard-mounted.
https://www.ebay.com/itm/232973683131

Seems to be a discrepancy re: whether the relay is 50-amp rated (listing vs datasheet for resistive load.)

[waughoo]

I tool like the idea of an easy to swap relay install.  Also allows for jumper activation in the event of failure far from home.

I like this idea, but it seems a bit overkill (though that is how I do most things anyway...)

https://www.speedwaymotors.com/Speedway-Single-70-Amp-Relay-Module,404373.html?sku=91003048&utm_medium=CSEGoogle&utm_source=CSE&utm_campaign=CSEGOOGLE&gclid=Cj0KCQiA0eOPBhCGARIsAFIwTs4HBXAY7iF0jLDsmkTfLG37Syeq9TYvCKaSbROc8H-QO6aJq5B51UYaAh7CEALw_wcB

[KWKloeber]

Alex that looks like it deserves the Lurch neat, sweet, petite award.  Very nice that it uses screw terminals rather than quick disconnects.

With the fuse, it seems perfect (subject of course to proven longevity?)



Note that I haven't yet seen those who tout the GP relay mod, to also caution that one then needs to install an additional fuse in the circuit!!  (more complexity, more unanticipated issues.)

IIWMRelay, for simplicity I would jumper the relay V+ screw to the B+ post and fire the relay using a negative wire.

"Interestingly" I ran across a 4001 relay that is bluetooth -- so long as the relay has power it can be fired via bluetooth.  I bought a small RF, remote-activated relay unit to be able to turn on my spreader lights before boarding (dock is typically pitch dark with blown-out bulbs.)  It isn't perfect (requires not misremembering to leave the FOB in the car, etc.)  That li'l relay box might get a stamp of approval if it works with the bluetooth relay.

[waughoo]

Ken,

Sounds like the solution for me then.  As for switching the wiring around to connect the negative on contact closure, I am not sure I will go that route simply because it will require some fiddling at the gauge panel to rewire it.

As you were explaining the bluetooth relay, I though, REALLY?!?? From Ken?  Then you exained your use case, and I thought, Brilliant!  I have always wanted something similar for returning to an anchored boat in the dark.  Dinghy disenbarkments under those circumstances are challenging at best!

[KWKloeber]

Ken,

Sounds like the solution for me then.  As for switching the wiring around to connect the negative on contact closure, I am not sure I will go that route simply because it will require some fiddling at the gauge panel to rewire it.

As you were explaining the bluetooth relay, I though, REALLY?!?? From Ken?  Then you exained your use case, and I thought, Brilliant!  I have always wanted something similar for returning to an anchored boat in the dark.  Dinghy disenbarkments under those circumstances are challenging at best!

Alex

Here's the relay.... (and apparently it can flash and dim too!!  A light show LOL)
https://triggercontroller.com/trigger-one-bluetooth-relay/

Using a V- trigger for the glow plug relay requires only to unscrew at its source the wire that feeds the preheat switch (it originates either at the key switch or the start switch depending on your panel) and move it to a ground terminal (a gauge or tach Neg post.)  EZ-PEAZY     At worst you'd need to make up a longer wire w/ two yellow #8 post ring terminals.  That's simpler than running a separate ground to the relay box (less complex, fewer wires/connections = better.)

You'd want to slide some HST onto the wire at both ends as an indicator that it's not a V+ lead.  I don't think ABYC has a standard for a V- control wire - so IIWMWire, I'd use yellow HST and put a black stripe on it.

BTW I don't mind adding the "complexity" of the spreader light trigger because (a) there's no other way to accomplish the goal (unlike the glowplugs) and (b) it's not a Class-A critical function (e.g., starting circuit) if it fails.

[waughoo]

Ken,

True... it isnt that hard to switch it to negative trigger.  I guess I am just being lazy.  I do have the glo plugs on the key switch.  Does that have a isolated contact for the glo activation or does it just use the 12v supply already into the switch for the ignition power?

Also, I am thinking about swapping the starter trigger wire (12awg currently in my panel) with the glow wire (#10) so my starter circuit matches the current spec and i can reduce the size of the trigger wire on the GP circuit since it will now be on a relay.  Thoughts?

[KWKloeber]

Ken,

True... it isnt that hard to switch it to negative trigger.  I guess I am just being lazy.  I do have the glo plugs on the key switch.  Does that have a isolated contact for the glo activation or does it just use the 12v supply already into the switch for the ignition power?

Also, I am thinking about swapping the starter trigger wire (12awg currently in my panel) with the glow wire (#10) so my starter circuit matches the current spec and i can reduce the size of the trigger wire on the GP circuit since it will now be on a relay.  Thoughts?

With the GP on the key sw, it uses its internal V+ bus and connects it to the external "I" (ignition, momentary contact) terminal (#8 screw) It's not an isolated contact (there's just one V+ wire going to the key switch.)

So ahhh ha I see the issue.  I was thinking that you had the separate pushbutton GP switch.  Tsk tsk, Catalina -- that setup w/ GPs on the key sw is not very smart - most key sws are not meant for high amps, especially on a 4 cylinder. 

Unless there was rewiring I'd think that your "S" wire (starter solenoid; yellow/red stripe?) is 16 AWG.  That was the Universal standard for the engine harness way back when and as far as I've seen CTY/Seaward used the same gauge down from the panel to the engine gummy bear plug.

IIWMB, I would use the PB start sw for my GPs and the key Sw to start.  That's how my panel is OEM (except a toggle sw not PB for the GPs.)
i.e., move the "S" wire from the PB switch to the"I" terminal of the key sw.
move the GP wire (gray, white, brown?) from the "I" terminal to the PB switch.
Remove the V+ feed to the PB sw (wherever it originates, probably the B+ terminal on the key sw) and move it to a Neg post (again might need a longer pigtail.)
Mark the old S wire (now GP wire) w/ yellow HST and a Sharpie black stripe.
Mark the old GP wire (now S wire) w/ yellow HST and a Sharpie red stripe.

OR, just fire the relay w/ the key sw?  The relay must be w/in 7" of the V+ source you use for the GPs otherwise you need to add a fuse on that (so therefore the relay should be close enough that running a Neg for the coil isn't that long.)

[waughoo]

All fantastic points Ken.  Thanks for thinking it through with me.  I have ordered one of thoae fancy relay sets I SHOULD be able to get it close enough in the engine bay to meet the 7" requirement (usimg the onboard relay board fuse).  For simplicity sake, I plan to fire the relay with the key switch.  If I am feeling "crazy" I might swap the GP wire for the start solenoid wire to meet the new spec for the start circuit.

[waughoo]

I got the relay module today.  In talking with the mfg who makes these as orders come in, he has PURPOSELY made the relays not swapable.  The whole circuit board is potted in an epoxy like substance.  He indicated that it is the blade connectors that eventually wear and cause a relay to fail.  He can say it better than I so I will copy his email below.

------------
No they do not plug in. That's why they hold up so much better.
I've had several customers over the years ask why the relays are not user replaceable on my relay boards. The reason is that almost all relay failures are due to them being plugged in a socket. Sockets get dirty and corrode over time which in turn causes heat to generate in the plug contacts. This heat get worse and worse over time till it overheats the relays and contacts and either damages the relay or burns up the connectors. All of my boards uses industrial relays that are soldered to the circuit boards and meant to last over a million cycles. I've used over 100,000 of these relays and to this date have never had an actual relay fail. I've warranty replaced only 4 relays and that was only because of physical damage to the outside of the relay. And any other issues have been input or board
related. My products are fully warrantied. So if one did ever go out I can replace it. But that would be extremely rare.
----------

It appears as though he has developed this product after many years of them being in service and designing the troubles out of them.  I look forward to getting this installed!

[KWKloeber]

Alex

Looks like a nice well-built unit - but based on experience I vehemently disagree w/ his concept where and why relays normally fail.

The rear wiper pooched on my Grand Caravan.  What did I trace it to?  A relay! 
Not one of the handful of the terrible plug-in ones in the power center -- but a soldered in relay on the PCB board, buried under everything in the power center.  What a stooopd design that is. 

BUMMER.  His design negates all the "back up benefit" of a simple, plug-in, instant, replacement.  I wonder if his warranty covers incidental damage if it fails when we'd most need it for an emergency start?  I'd make up at least a jumper to clip on or a permanent panic button (and mount it very accessible.)

[waughoo]

He claims he has only replaced them for mechanical damage rather than use failure.  The fact that the terminals are right there on the front makes it super easy to jumper the connection and activate the glow plug circuit.  Seems pretty reasonable to me.  The robustness of the rest of the board makes me feel pretty confident it will perform for many years without incident.

[KWKloeber]

....OR use the dual relay version and there's the backup already installed; just move the trigger wire from one to the other.  Unfortunately, they're quick disconnects but the world isn't perfect.

[waughoo]

Relay got installed today.  I wired it up with a #8 from the starter lug, and two #10s to the glow plugs (one at each end of the run of 4).  I decided on two #10s as everything I could find said #10 was on the small side for the 45amps I measured when testing the glow plugs.

While I was at it, I added the engine ground buss with a #6 from the lower starter bolt.  I then moved the ground wires from the exhaust manifold to the ground buss.  All seems to be working fine.  I am quite happy with the relay module.

[KWKloeber]

Relay got installed today.  I wired it up with a #8 from the starter lug, and two #10s to the glow plugs (one at each end of the run of 4).  I decided on two #10s as everything I could find said #10 was on the small side for the 45amps I measured when testing the glow plugs.

While I was at it, I added the engine ground buss with a #6 from the lower starter bolt.  I then moved the ground wires from the exhaust manifold to the ground buss.  All seems to be working fine.  I am quite happy with the relay module.

Sweet. 

'Fresh my memory - have you moved the bty cable to the starter bolt?
The Neg block can be used for other negatives as well (to eliminate runs to the panel.)

Inside the engine compartment 10 awg is good for 51 amp; 8 awg 68 amp.

[waughoo]

When you ask about the battery cable, are you asking about the negative or the possitive? 

The negative cable presently resides on the bell housing bolt right behind the starter.  It occured to me that perhaps moving that to the same bolt on the starter that I took the #6 ground buss wire from would be the best idea.  My reason for not doing it that day had a lot to do with time and the length of the starter bolt.  I was concerned I wouldn't have enough bite for the starter threads without getting a longer bolt at the hardware store.

I cpuldn't find an inline ATC fuse  holder with #10 tinned wire at the marine store so I have to order one so I can complete the engine harness wiring protection.  Otherwise, I believe I can mostly check this area off the list.

As for wiring gauge sizes, I was using the blue seas chart at the 10% allowable drop.  They wanted #8 for 50amps.  I did see somewhere on WM a chart that #10 was okay for 50 amps but couldn't cooberate that with any other resource so I opted for the double run of #10.  Is there a chart you use Ken?