I had some fuel problems with my cooper when I put the blower on, and as part of fixing it, I'd changed the fuel pump, and installed a high-volume needle and seat...

the problem I was solving was that at wide open throttle it was starving of fuel, it'd empty the bowl - the fuel system wasn't getting enough in there to keep it full. Not enough volume was getting through, either by restriction, or by not enough pressure.

The fuel pump change hadn't made any difference, and I was a little dubious about it's pressure, it has a sticker on it saying 4psi, but it's been sitting around 5-6 years, so I thought maybe it was bypassing inside, but it was working so I left it

The high volume needle and seat was the ticket - sh!tloads of fuel through it - $18 very well spent. If you think about it, the needle and seat is the biggest restriction, it's a ~2mm hole with a rubber thing stuck in it - you can have all the of big fuel lines you want, but it's still gotta get through that little hole

Anyway, problem was solved a week or two ago, been going really well. I had a car club meeting on tuesday night, and as I got on the freeway on the way home, the engine died as if it'd run out of fuel. I could start it, drive a little, and it'd die again. I took the lid off the float bowl and made sure it was getting fuel through, which it was, and I decided that the pump was now just too weak to even open the needle and seat. Then my mate pulled up behind me, so he very kindly towed me home.

In the garage I swapped back to the old (trusty) fuel pump, I turned on the ignition, it pumped, I went to bed.

So yesterday morning I started it up, backed out of the garage and it died - bum - I'm looking after dad's car, so I put the cooper back in the garage and drove dad's car.

I didn't' think about it last night, too sleepy

Just now I went out to the garage all set to nut this one out - didn't make sense... I took the lid off the float bowl, looked normal, fiddled around, the float wasn't sitting properly, the needle was jammed shut - hmmmm - took the float off, needle and seat is fine, hmmm - what the!!

The seat had unscrewed itself to the point where it was pressing against the float, pushing the float down as far as it'd go and holding itself shut where wouldn't go any further!

I was sure I'd done it up tight, because remember it took ages to find a 9mm socket

It's got a dab of loctite on it now

Interesting problem / diagnosis there.

Good info to keep in mind when chasing problems around fuel supply.

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Dean Hutton's first car was a Mini.

we should call you Angela Landsbury

High Flow needle and seat for SU's? Never heard of em? Is this something Midel stock?

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http://www.youtube.com/user/Hanras

that's where I got it from - really neat bit of gear, and uses a ball bearing to seal so I don't see it wearing out any time soon. I got the .125" (3.2mm) variety

https://sumidel.site-trust.net/cat/inde ... id=1540417

the price on the phone is more than the web - they're rectifying that at some point

Matt Reid told me they were available - I'd been trying to drill a standard one out (using the lathe), but I couldn't make the viton tip seal properly. It'd either stick shut, or not shut at all

Wow. Interesting. Ive never suffered with fuel starvation however. What size carbs do you have? I wonder if this would be a worth while upgrade to do anyways??

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http://www.youtube.com/user/Hanras

single 1 3/4" feeding a supercharger... and probably using more fuel than it needs

that said, if I was rebuilding a carb for a normal car, for the price I think I'd chuck one in anyway

Oh sh*t! True! I didnt know you were blown! Is that a SC12 jobbie?

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http://www.youtube.com/user/Hanras

ha - read the first line of the my post at the top - and yep, SC12 - I'm up to $445 so far

Do'h!!!!! When I see a large post I tend to skim read....!

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http://www.youtube.com/user/Hanras

$445 Simon!!!!!! How did you get your hands on that sort of cash??????

Doogie

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I won Hay once, here's the pic to prove it..


Hay, it's not about the car, it's not about the venue, it's about the people that come here. Peter Dwyer, Mayor of Hay NSW.

dad owed me $180 of it, the rest was in small change so went mostly unnoticed

I hear ya brother


Doogie

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I won Hay once, here's the pic to prove it..


Hay, it's not about the car, it's not about the venue, it's about the people that come here. Peter Dwyer, Mayor of Hay NSW.