Fuel gauge resistance?!

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broompisces
Posts: 156
Joined: Tue Feb 17, 2009 8:20 pm
CMBA Member: 768
Location: Glasgow, Scotland

Fuel gauge resistance?!

Post by broompisces »

Hello all,
I am replacing my 49 year old internal fibreglass fuel tank in my Broom Pisces - mainly because it leaks like a sieve!
A local precision engineering company will be making me a new tank from stainless steel, using the current tank as a template.
I am going to order a new fuel sender for the new tank (the magnetic float "pole" type), whilst still using the original fuel gauge.
I was poised to order a fuel sender when I noticed that they come in different resistances; 0-190 ohm for European fuel gauges and 230-30 ohm for USA fuel gauges.
Now, my fuel gauge is an original 1960's Mercruiser one - should I be going for the 230-30 ohm sender unit or the 0-190 ohm one?
Many thanks in anticipation of your help / advise.
Ian.

Diomedea
Posts: 158
Joined: Sat Apr 30, 2011 8:36 pm

Re: Fuel gauge resistance?!

Post by Diomedea »

Not trying to appear obvious but can you measure the resistance of the old one?

broompisces
Posts: 156
Joined: Tue Feb 17, 2009 8:20 pm
CMBA Member: 768
Location: Glasgow, Scotland

Re: Fuel gauge resistance?!

Post by broompisces »

I measured the resistance.

However - the meter read circa 90 ohms when it was attached to two posts on the fuel gauge. But my choice for fuel sender is a 230 - 30 ohm sender or a 0 - 190 ohm sender.

Can anyone advise what a resistance of circa 90 ohms across the fuel gauge would indicate which sender I should get? I disconnected all wires from the gauge before testing the resistance.

Diomedea; the reason I hadn't measured it was the distance from my home to where the boat is wintered. I was hoping someone on the forum would've known.

Anyway - after a morning jaunt to the boat yard, I at least now know what resistance the meter across the gauge yielded!
Attachments
IMG_1492.JPG

haventaclue
Posts: 610
Joined: Wed Mar 31, 2010 12:13 am
CMBA Member: 924
Location: Donegal, Ireland

Re: Fuel gauge resistance?!

Post by haventaclue »

If your gauge is USA made,then you need a 0-190 sender.Also Sent PM.
no matter how bad it is,it can always get worse,I'm an optimist

broompisces
Posts: 156
Joined: Tue Feb 17, 2009 8:20 pm
CMBA Member: 768
Location: Glasgow, Scotland

Re: Fuel gauge resistance?!

Post by broompisces »



Got my new fuel sender; seems to work well!

broompisces
Posts: 156
Joined: Tue Feb 17, 2009 8:20 pm
CMBA Member: 768
Location: Glasgow, Scotland

Re: Fuel gauge resistance?!

Post by broompisces »

I decided to go for the 240 - 30 ohm sender as the fuel gauge is an original 1960s one. Looks like I guessed right as the video above shows. Usually, if I have a choice of two items; one right and one wrong, I always choose the wrong one. The picture below shoes the old sender and the replacement one.
Attachments
IMG_1497.JPG

broompisces
Posts: 156
Joined: Tue Feb 17, 2009 8:20 pm
CMBA Member: 768
Location: Glasgow, Scotland

Re: Fuel gauge resistance?!

Post by broompisces »

Here's the fuel tank - nearly 50 years old and leaks like a sieve. Once replaced, It'll be nice not having the sniff of 4 star mixing with the natural air of Loch Lomond.
Attachments
IMG_1509.JPG

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