Two senders on Fuel distribution Plate

[Kevin Tisdall]

I am in the process of doing the fuel cooler removal.  I have the kit from Seaboard.  The engine is a 6bta5.9 330-M.  Boat is a 2001 mainship 390. I expect the engine is 2000-2001 vintage (original to boat).

I got partway into it and find the following:

I don’t have one oil sender I appear to have two.   I expect someone replaced stock sender (at least one).  The big one to left (See PIC1) has one or the two wires turned back and taped to the wire conduit.  You can sort of see the taped over connector in the pic.

The sender to the right has two connections.  The harness wires (2) have one wire  connected and one taped off and the second connection to that sender is wired up thru a black conduit to a sender on the cylinder head.  Not at all sure what that is doing – can anyone give info/guidance?   Boat has two stations and oil pressure reads same at both.  See PIC2 for view of the sender in the head – black conduit.

How do I complete this install?  Should I “T” off the oil sender adapter that goes into the new location in the side of the block?

–Kevin

 

Topic

[pwrobert]

Try an adapter

For just one more sender there is no need for a “T” if you use the third Oil sensor hole in the block.  It requires an adapter into the British 9/16″ O-ring Straight thread hole.  Get an adapter for the sender – 9/16″ Male to 1/8″ NPT or whatever sender thread you will use.

I did this because my bridge gauges require separate type of senders than the salon and the LOW pressure switch doesn’t care and will sound two buzzers if desired.  I just have one loud one.

“T”‘s work ok but vibration diesels can lead to some leakages if not done carefully and fully snugged up.

[Kevin Tisdall]

very helpful. I am now considering using the old oil feed to the multi block for the pressure switch and the block oil gallery for the alarm switch. Fewer T connections , etc.

That is, if I can adapt the old oil to block hose feed to the pressure switch….

–Kevin

[Rob Schepis]

Be sure the T is a steel fitting if you go that route.  Or just move to an oil galley port.

Yes the switches can be interconnected,

Both are covered here:  https://www.sbmar.com/articles/redundant-alarms-least-expensive-engine-insurance/

 

[Kevin Tisdall]

Ill have a look and thanks for responding.  Happy new year.  <br /><br />

–Kevin 

[Tony Athens]

Can you do this?  100% safe if you do it right.

The sender (not the switch) has a ground you can use to ground the switch if needed..

[Kevin Tisdall]

Ok good to know.  Id love to put them on separate oil ports in the block (buy another adapter from sbmar).  Would need to know where to put it though. <br /><br />

–Kevin 

[Alex]

True. My low oil psi switch was also connected to a head coolant switch. Perhaps wired in a way that any of the two conditions would trigger the alarm – low oil psi and/or high coolant temp. <br /><br />Lets see what others say is the correct sender and switch plumbing and wiring for gauges and alarm triggers, when removing the combo/fuel block.

[Kevin Tisdall]

Senders

Im also thinking the second is a pressure switch that also leads to a head temp sender.   I can probably check that by grounding/removing the leads.  

I’m hoping a stainless T off the port adapter in the kit is going to be ok to support the two senders mounted to a T.  Id hate to have it break in operation.

 –kevin 

[Alex]

I also removed the fuel block but haven’t reinstalled the senders on rebuilds.

If not mistaken the larger one is the pressure sender ohm range matching helm gauge and the small one is a low pressure switch normally open for the alarm, closed at key on before start up and if low psi -8?

I have the same question- May need a T to connect both again to a single engine block port above.

 

 

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