Temperature gauge issues? Can't get a temp reading?

[dubs283]

use a hose clamp to secure a ground wire the the hex of the sensor, run the other end to a bolt.

This "backyard" repair would not only eventually fail, it would look terrible and let everyone who sees it know that OP does not care about or respect the intended design and operation of the system.

So many times I come across items that are improperly repaired that it begins to make things unsafe. Is it really that difficult repairing items to meet factory specifications people on this forum need to offer advice on "workaround" repairs?

 

[Bondo]

This "backyard" repair would not only eventually fail, it would look terrible and let everyone who sees it know that OP does not care about or respect the intended design and operation of the system.

So many times I come across items that are improperly repaired that it begins to make things unsafe. Is it really that difficult repairing items to meet factory specifications people on this forum need to offer advice on "workaround" repairs?

Ayuh,..... The sender needs a solid ground, so I'd start at the battery ground lug, 'n work yer way to the sender, Cleaning to shiny metal Clean, All of the connections,......

I doubt the original sealant on the sender is the problem,.... I use sealant paste on senders,......

 

[achris]

..., if I quickly use a piece of wire to short the smaller threaded side of the sender unit to the block (so the temp gauge goes to max, then remove shorting wire) then it will settle back at the 160f temp on the gauge until I turn the engine off. Then same problem when restarting, no temp reading...

This sounds like a sticky gauge. Easy way to test. Once the engine is warmed up, shut it down, then with the key OFF, remove the tan wire from the back of the temp gauge and measure it's resistance to ground. It should be around 120Ω. If it's nearer infinity (LOTS and LOTS of Ω) then you have a wire/sender/ground issue... If it's around 120Ω, you can swap another gauge (oil or trim) and see if that reads more near the middle (temp, oil and trim are all the same gauge, 240-33Ω, just with a different print on the plate behind the needle )...

Chris......

 

[MarcelSydney]

Ok, thanks will try these ideas.

 

[j cat]

Ok, thanks will try these ideas.

the temp sender has ONE connector ... setup the ground wire to the sender case ... I wire brush the threads clean and I use anti seize ...use the ohm meter to inspect the temp gauge case to the battery ground / engine block ..zero ohms ...

 

[MarcelSydney]

This sounds like a sticky gauge. Easy way to test. Once the engine is warmed up, shut it down, then with the key OFF, remove the tan wire from the back of the temp gauge and measure it's resistance to ground. It should be around 120Ω. If it's nearer infinity (LOTS and LOTS of Ω) then you have a wire/sender/ground issue... If it's around 120Ω, you can swap another gauge (oil or trim) and see if that reads more near the middle (temp, oil and trim are all the same gauge, 240-33Ω, just with a different print on the plate behind the needle )...

Chris......

Thanks Chris. Finally got around to this.
Spot on. Resistance was about what you said. Disconnected the connector, and watched the resistance drop as I ran the boat on muffs from cold to warm.
Swapped the connector to the oil pressure gauge and the oil pressure gauge went up.
Must be a broken gauge. Doesn't appear to be serviceable so will have to find one that's a close match.
Cheers, thanks for your help. Wouldn't have guessed it was the gauge.

 

[achris]

.. Doesn't appear to be serviceable so will have to find one that's a close match..

If it's a Merc gauge no, not serviceable.

If you post a photo of the gauge we might be able to match it up for you... At least give you an idea of where to look.

Chris....

 

[MarcelSydney]

If it's a Merc gauge no, not serviceable.

If you post a photo of the gauge we might be able to match it up for you... At least give you an idea of where to look.

Chris....

Here it is. Not sure if it's mercury, doesnt seem to say.. Its from a 1998 Maxum.
I'll just google something similar

 

[MarcelSydney]

Actually, seem to have found original Maxum branded ones by Faria on ebay. Old stock parts. Ill give that a shot.

 

[achris]

Here you go...

Faria Boat Temperature Gauge GP7192A | 2 Inch Silver Black

Boat part number 1007660 is a new temperature gauge from Faria, part number GP7192A .

www.greatlakesskipper.com

 

[MarcelSydney]

Here you go...

Faria Boat Temperature Gauge GP7192A | 2 Inch Silver Black

Boat part number 1007660 is a new temperature gauge from Faria, part number GP7192A .

www.greatlakesskipper.com

Thanks

 

[MarcelSydney]

Ripper! It works. Sticky gauge, how 'bout that.
Got a new speedo from that mob too. Matches exactly.
Thanks a lot for your help.