2003 Marlin 300 Fuel sender

pnwspearo

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Hey all,

Had my 300 Marlin for a few years and finally joined this forum. Seems like a great resource so here's my first question.

One of my fuel tank sending units is no longer working below about half a tank. I'm hoping I can pull the unit and fix it but if not I want to be ready to replace it before I pull the old one out. Does anyone know what the unit make and model is so I can get it ordered?

Thanks!
 

seasick

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It could be a generic adjustable arm type , easy to find but not as good you can get with something from KUS formally Wema which has no float arm. Unfortunately, you need to know the tank depth (less an inch or so) to order the Wema.
Keep in mind also that if your tank is relatively full, fuel can spill out of the opening when you remove the sender
There are others like the KUS out there. here are some examples and while at it, get a new gasket. (standard USA senders are 240 to 30 ohms, 5 hole flange.
 

DennisG01

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And... it only takes a few minutes to pull a sender out and check it for model ID or measure the tank. Just match-mark the sender to the tank, first. So it's not like you're really saving any time. It's a quick check.

Plan on replacing - I don't even know, off hand, if there's anything that can be "fixed". How were you planning on fixing it?
 

seasick

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Just to reiterate a suggestion from Dennis. The 5 hole flange is not symmetrical but sure as heck looks it. Make a mark on the tank and the flange so that you can align things up later. If you change senders, make you you have the gasket aligned too.
 
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pnwspearo

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Roger that Dennis, thanks. Since the sender stops working at about half a tank I am hoping its simply getting jammed somehow. But I'll plan on just replacing the whole unit and since I'll have the cover off anyway I'm thinking now I might as well replace both senders.

Thanks seasick for the link and advice. I wouldn't have thought to mark the flange. I'll be installing new gaskets for sure as its just good practice. Getting rid of the float arm would be nice. I'm all about getting rid of moving parts where I can.
 

ScottyCee

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I learned that 5 screw hole trick the hard way. Fortunately I cottoned to the asymmetry of it early before I got out any additional tools. ;)
 

leeccoll

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Welcome to the forum pnwspearo!

I added a KUS last summer. You will love it.

Just adding if you decide to change the gasket, I upgraded from cork to their nitrile rubber gasket. I highly suggest that for added leak protection. And tighten up the flange screws in a star pattern.

Best of luck,

Lee
 

pnwspearo

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Welcome to the forum pnwspearo!

I added a KUS last summer. You will love it.

Just adding if you decide to change the gasket, I upgraded from cork to their nitrile rubber gasket. I highly suggest that for added leak protection. And tighten up the flange screws in a star pattern.

Best of luck,

Lee

Thanks Lee! Good advice. I'll get the nitrile
 

seasick

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And don't over tighten the screws:)