5.7gs temp gauge wiring

[Galvez83]

Can someone help me regarding a wiring question. My 2001 Wellcraft 2600 Martinique with a 5.7GSPEFS had the temp gauge working fine and all the sudden it stopped showing the temp at the gauge. I changed all gauges as they where tired and worn out. No change with new temp gauge the rest are working fine. I also checked the sender and its within resistance range (also new, changed 2 months ago) located at thermostat housing. In the manual its showing tan wire for my temp sensor. While there is a discrepancy my sensor is the one with only one spade terminal and it should be tan/ w black tracer if you follow the engine wiring diagram. My engine only has one temp sensor. Anyway, i tested continuity from the tan at the gauge to the spade terminal and i get...nothing. I also found near the helm a tan with a tracer black and another tan with tracer blue that both look like each wire was crimped and broken. Both terminals are not the same at both tan w/ black trace and tan w/ blue tracer. I am fully lost. Any help is appreciated to narrow down the issue.

 

[Galvez83]

Can someone help me regarding a wiring question. My 2001 Wellcraft 2600 Martinique with a 5.7GSPEFS had the temp gauge working fine and all the sudden it stopped showing the temp at the gauge. I changed all gauges as they where tired and worn out. No change with new temp gauge the rest are working fine. I also checked the sender and its within resistance range (also new, changed 2 months ago) located at thermostat housing. In the manual its showing tan wire for my temp sensor. While there is a discrepancy my sensor is the one with only one spade terminal and it should be tan/ w black tracer if you follow the engine wiring diagram. My engine only has one temp sensor. Anyway, i tested continuity from the tan at the gauge to the spade terminal and i get...nothing. I also found near the helm a tan with a tracer black and another tan with tracer blue that both look like each wire was crimped and broken. Both terminals are not the same at both tan w/ black trace and tan w/ blue tracer. I am fully lost. Any help is appreciated to narrow down the issue.

 

[ESGWheel]

If I may summarize your issue:

• Was working, suddenly not.
• Components good (both sender and gauge) but do not have connectivity been sender and gauge.
• Further there is some confusion over the color of the wire(s).

Thus it sounds like simply running a new signal wire would solve the issue. It may be a bit of a pain but should work. Alternatively if want to use as much of the original wiring as possible and/or repair where its failed than getting a wire tracer (link) will help you trace down the wire(s) and if there is any breaks. These are cheap devices and uses a tone generator that allows you to ‘trace’ that wire without the need for really long leads on your multimeter. See this link for how they work.

 

[Galvez83]

If I may summarize your issue:

• Was working, suddenly not.
• Components good (both sender and gauge) but do not have connectivity been sender and gauge.
• Further there is some confusion over the color of the wire(s).

Thus it sounds like simply running a new signal wire would solve the issue. It may be a bit of a pain but should work. Alternatively if want to use as much of the original wiring as possible and/or repair where its failed than getting a wire tracer (link) will help you trace down the wire(s) and if there is any breaks. These are cheap devices and uses a tone generator that allows you to ‘trace’ that wire without the need for really long leads on your multimeter. See this link for how they work.

I take it back at least portion if what i wrote. Instead of full tan at the sender its tan with black tracer. I found a a broken tan and black wire by the helm. Although i cannot find the missing end. Unless it's ment to go with the tan and blue tracer. When i touched the tan and blue tracer wire to the temp gauge it went to full hot. Still have many questions. Where is the tan and blue tracer supposed to go at the helm? Where is the tan and black suppose to go at the helm?

 

[Chris1956]

A lot of sterndrives have a temp gauge and a overheat alarm. Each of those have their own senders. On my MerCruiser, both sensors were in the thermostat housing.

If you proved the gauge sender is good, and the gauge is good, the wiring is likely bad.

 

[Galvez83]

Does anyone have a dash gauges wiring diagram for a Volvo penta 5.7GS carbed? That might help me track down where the tan w/black and tan w/blue go at the dash.

 

[ESGWheel]

Galvez83,
I just noticed you have this same post going in Electrical.

Perhaps one of the moderators can merge the posts into one on the electrical side to allow a more coherent back and forth.

 

[Fun Times]

One other thought is how sure are you the engine is actually getting up to full temperature? If the thermostat is stuck open say due to debris than more often than not the temp gauge won't go up much at all especially if the gauge starts at say 100 degrees... May want to verify the temp is getting up around 160.

Below is some homework for you.
Engine Cable Wiring Diagram
5.0 GL and 5.7 GS Models
1 Trim Sender
2 10 Amp Fuse, Trim/Tilt
3 Tachometer Amplifier* = GR for Gray and a Black for ground.
4 Relays, Trim Motor
5 Oil Pressure Sender, Gauge = BL For Blue.
6 Circuit Breaker, Trim/Tilt
7 40 Amp Fuse, Instrument Harness
8 Electric Choke, Carburetor = PU for Purple and a Black for ground.
9 Water Temperature Sender, Gauge = T For Tan.
10 Relay, Fuel Pump
11 7.5 Amp Fuse, Fuel Pump
12 Diode = Orange to Fuel pump Relay (10) then to Yellow/Red to 10 pin...Also there's one in Green from Alternator to pump relay.
13 Relay, Starter
14 Alarm = T/SB =(Tan / Single Black) And ((PU = Purple))
15 Water Temperature Switch, Alarm = T/SB (Tan / Single Black) ((Looks like a Spade connector in the Manual)).
16 Oil Pressure Switch, Alarm = T/SB (Tan / Single Black) ((Looks like a Spade connector in the manual)).

And there shouldn't (< that I recall) ((or doesn't appear to)) be a tan w/ blue.

Item number 20,

Intake Manifold

Make sure to keep your Volvo Penta Genuine!

www.volvopenta.com

Item number 30 though it's not the correct one shown as noted below for you,

Cooling

Make sure to keep your Volvo Penta Genuine!

www.volvopenta.com

To help give you an idea of wire connection call outs before finding the wiring diagram in color below.

Engine Harness

Make sure to keep your Volvo Penta Genuine!

www.volvopenta.com

Here's all your engine parts,

Volvo Penta Shop

Find and buy the full Volvo Penta aftermarket assortment for marine and industrial applications. With more than 200.000 genuine parts to support all maintenance and repair you will find all you need. Identify the Volvo Penta engine, shield or drive when looking for spare parts, maintenance...

www.volvopenta.com

The following is of something you will need to be aware of as for some odd reason your parts diagram shows a 2-wire type sensor at the T/housing but you should have 1-wire sensor?...Also, the sensor locations are noted in the followings,

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