f8b carby issues.

MightyBoy tech questions and answers.
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800beast
Posts: 44
Joined: Wed Mar 11, 2015 11:37 pm
Location: adelaide

I started my f8b for the first time in 13 years, found the primary throat in the carby continued to drop fuel in after it was switched off and also the secondary jet thing rattles around and comes out really easy.
Does this look normal?
Does this look normal?
Is it slightly worn or is it rooted?
Will the carby need more than a rebuild kit?
also the fuel pump leaks, can I use one of these to replace it..
http://pages.ebay.com/link/?nav=item.vi ... 75&alt=web
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Brayden
Posts: 9101
Joined: Sun Apr 11, 2004 3:09 am
Location: Canberra ACT
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Fuel running in after the engine is switched off could be caused by:
- the fuel cut solenoid not working,
- dirty/worn needle and seat,
- the float is damaged.

The rattling venturi is a common problem, they're only push fit, and over time the retainer becomes worn. Simple fix by packing one side of the venturi shaft to hold it firm.

A rebuild kit should do the trick, unless the float is damaged (and they are repairable, but replacements are difficult to find). When rebuilding it is a good idea to inspect the secondary throttle vacuum pot (also a common problem) and with an automatic, also check the idle-up vacuum solenoid. Replace as necessary.

There are many options for replacing the mechanical fuel pump with an electric unit. The type you choose will dictate how noisy it is. (Generally speaking, cheap = noisy). Technically with an electric pump you're legally required to install a switch that automatically kills the pump when the engine stops but the ignition is still on - this is to avoid the pump continuing to run after a crash.
F8B EFI turbo - Three pots and a snail.
800beast
Posts: 44
Joined: Wed Mar 11, 2015 11:37 pm
Location: adelaide

Awesome, I was worried about the venturi because it looks like it's snapped on down the hole.
I'll order a rebuilt kit and give her a birthday.

Ah ok, I'll have to have a think about how to wire in a relay for one.

Also I have pulled my water pump off to replace it and I think I have taken the timing belt off correctly, But is there a simpler explanation or guide to fitting a new one back on because the manual makes no sense to me.
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Brayden
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Joined: Sun Apr 11, 2004 3:09 am
Location: Canberra ACT
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With the timing belt you just need to align the two pulley markers to TDC (as marked on the rear timing belt cover. When reinstalling the belt, refit the tensioner first, but only hand tighten the bolts. Fit the belt and then put pressure on the tensioner with a long screwdriver, tightening the bolts before you release the screwdriver.

If you've ensured that the two pulleys are lined up then you should be sweet.
F8B EFI turbo - Three pots and a snail.
800beast
Posts: 44
Joined: Wed Mar 11, 2015 11:37 pm
Location: adelaide

Excellent Thanks for that mate, that makes it sound a lot easier.
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Brayden
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Joined: Sun Apr 11, 2004 3:09 am
Location: Canberra ACT
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To clarify, the pulley markers need to be aligned before you remove the old belt. If you try and turn the pulleys with the belt removed it will likely result in some bent valves depending on how much force you use.
F8B EFI turbo - Three pots and a snail.
800beast
Posts: 44
Joined: Wed Mar 11, 2015 11:37 pm
Location: adelaide

Well I removed it like it said in the manual.. as in the bottom pulley at 50-70 degrees before the marker but when the tensioner got released the top cam sprang around a little way.
I hope it's all good, ill Have to wait And see I guess
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