Samurai 1.6 fuel pump wiring

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Larry
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Samurai 1.6 fuel pump wiring

Post by Larry » Sat Nov 21, 2020 3:29 pm

Hi all,

I've had to fit an electric fuel pump as my 1.6 8v has no mechanical pump.

I've stolen an ignition live that I think was spare after removing the old aisin carb. Runs great as it is...

However, it's not ideal that the pump stays going in the event of a crash where the engine might cut out but the ignition could be left on.

Is there a simple way to get an live that is only live when the engine is running? From the coil or the oil pressure switch maybe?

What have others done?

Thanks 👍
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Larry
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Re: Samurai 1.6 fuel pump wiring

Post by Larry » Wed Nov 25, 2020 9:46 pm

So having done some more reading, I think taking a "T" off the 12v feed from the instrument cluster to the oil pressure switch might work. I'll use this to trigger a relay to power the fuel pump.

I'll then either
A) package a non return valve on the fuel line

B) add a push button primer
or

C) fit a timer relay to prime the pump thats triggered by ignition live. Similar to glow plugs on a diesel.

Any better ideas, please let me know! ;)

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Jordi
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Re: Samurai 1.6 fuel pump wiring

Post by Jordi » Thu Nov 26, 2020 6:45 am

If its a self priming pump shouldn’t need a priming switch.

When the engine turns over to start and the oil pressure builds the pump should kick in.
1988 Samurai - Truck Cab & Tray Back - 1.6 8v & HIF44 - Snorkel - Stack Exhaust - PAS, YJs & 33s - Trussed, Gusseted & Pumpkin Capped Axles - 4.3 R&Ps - 4.16 T/Box - Rear Air Locker - Full Float Back Axle & Discs - RCV Front Shafts - X-Eng Handbrake - Custom Fuel Tank

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Larry
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Re: Samurai 1.6 fuel pump wiring

Post by Larry » Fri Nov 27, 2020 5:10 pm

Thanks Jordi, that's a fair point, I'm not sure exactly hoe the pump works but judging by the in line filter between the pump and the carb it doesn't appear to drain back, so I should just try without first and see how I get on :thumbup:

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Anton
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Re: Samurai 1.6 fuel pump wiring

Post by Anton » Sat Nov 28, 2020 4:36 pm

Thinking about it, your solution would have the added benefit of saving your engine if you crack your oil pan or kill your oil pump. It's a pretty good idea.
1985 SJ413VX (SJ50V) with SPOA, rear disc brakes, 31x10.5R15 Kaiman Malatesta tyres, an MOT and a lot left to do!

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Jordi
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Re: Samurai 1.6 fuel pump wiring

Post by Jordi » Sat Nov 28, 2020 6:20 pm

The instructions for most electric pumps have them wired via the oil pressure switch for safety.
1988 Samurai - Truck Cab & Tray Back - 1.6 8v & HIF44 - Snorkel - Stack Exhaust - PAS, YJs & 33s - Trussed, Gusseted & Pumpkin Capped Axles - 4.3 R&Ps - 4.16 T/Box - Rear Air Locker - Full Float Back Axle & Discs - RCV Front Shafts - X-Eng Handbrake - Custom Fuel Tank

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Larry
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Re: Samurai 1.6 fuel pump wiring

Post by Larry » Sat Nov 28, 2020 10:43 pm

Anton, I thought so too! A nice safety net :thumbup:

Jordi, that's interesting, mine didn't come with instructions but it makes sense.

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Anton
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Re: Samurai 1.6 fuel pump wiring

Post by Anton » Sun Nov 29, 2020 2:22 am

I don't remember my pump having instructions either. It was a facet pump, so maybe it did and I just did the typical bloke thing and ignored everything in the box but the pump...
1985 SJ413VX (SJ50V) with SPOA, rear disc brakes, 31x10.5R15 Kaiman Malatesta tyres, an MOT and a lot left to do!

My: Build thread To-do list Pay and Play map

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