F8b inlet manifolds

MightyBoy tech questions and answers.
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jason
Posts: 181
Joined: Wed Jul 14, 2004 11:04 pm
Location: Sale, VIC

I have posted on the wtb section for an inletmanifold for a f8b. Have found another in the shed but it doesnt haave vaccuum gear at back. Any idea if it can be used as a replacement until i get time to get snapped bolts out?

Will resize pics to upload later but alternative manifold has no egr hole or vaccuum gear and has heat sensor with 'spike' on end, not the tab
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Eamon
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Joined: Fri Apr 29, 2016 10:49 pm

The vacuum pot on the end is only used for the auto mightboys, if your Mb is manual you will be fine
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jason
Posts: 181
Joined: Wed Jul 14, 2004 11:04 pm
Location: Sale, VIC

Here are the pics. I was sure that these were off a manual sb308 alto. Happy if i can use the older manifold, do i need to block vaccuum lines on carby or just disconnect?
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Brayden
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Location: Canberra ACT
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The vacuum pot on the back of the manifold is for the emissions gear, not anything to do with auto box. ;) You can remove and plate it, or leave it in place disconnected and remove/plug the relevant vacuum hoses. Sensors work the same, just have different connectors.
F8B EFI turbo - Three pots and a snail.
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jason
Posts: 181
Joined: Wed Jul 14, 2004 11:04 pm
Location: Sale, VIC

Thanks for the reply. The vacuum ports on the bottom of the carby that connect to the pot at the back and side are ok to block? Will try get pics of carby tomorrow to help clarify. I am still a bit confused as the carby and manifold were off a manual that went into an auto f5a donor car. Am i right in thinking that the ports in the f5a are a fair bit smaller than those in the f8b, just trying to make sure im not mixing them up as they have been sitting in shed for 5 years.
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jason
Posts: 181
Joined: Wed Jul 14, 2004 11:04 pm
Location: Sale, VIC

Decided to do head gasket and found leaky water pump at same time. There is corrosion in the water jacket on the head and water pump too . Any ideas how to stop this from spreading? Are there more earths than from the rocker cover and geaarbox to battery?
J
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Brayden
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Location: Canberra ACT
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Once the corrosion starts you can't do much except flush the coolant system and fill it with the right mix of anti-freeze/boil with corrosion inhibitor and demineralised water. If the corrosion is in the face of the head then best to get it skimmed, or find a replacement. New F5A and F8B heads can be found pretty easily.
There should be an earth from the battery to gearbox and battery to body (behind the P/S headlight).
F8B EFI turbo - Three pots and a snail.
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jason
Posts: 181
Joined: Wed Jul 14, 2004 11:04 pm
Location: Sale, VIC

There was some but it was across the water jacket. The corrosion was blocking a lot of the flow through the holes in the head gasket. Maybe the coolant mix was diluted and boiling as the gasket looked intact?
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Brayden
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Corrosion eats away at the water jacket, if yours is restricted then it sounds like rust accumulating from the block.
Without seeing pics I'd guess the whole motor needs an acid bath and rebuild.
F8B EFI turbo - Three pots and a snail.
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