another HIF44 turbo carb qustion.. regarding the "blocking of the bowl vent"
Turbo Mini Forums

ok keeping it sort i blocked this port as per the normal "http://www.turbominis.co.uk/forums/index.php?p=vt&tid=6298" and i seemed to get an air lock situwation.. it ether got zero fuel to the bowl or flodded the bowl so i un blocked this port and all was good untill i tryed to make boost it simply runs way lean then dies as per the like says it will

so my qustion is can i connect it to the plenum so as the bowl see boost pressure and maintains fuel entreing the engine?

ive checked the reg and its giveing 3-5psi and will rise 1:1 with compressed air put in where the plenum normaly dose so happy to rule that out

its wird that when blocked it floods the engine or starves it??? the plenum gasket had two holes so was the same no matter what way it was installed it didnt cover the hole i cheched that lol

Sounds like the float bowl isnt getting its pressure reference,
T'ing this into the plenum - fpr line is known as the 'T peice trick'

Yes i moved to the darkside

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i see little confusing as the pic with where things go says to block it maby it should say t in to plenum-reg line

i shall give it a test run and see what happens

No im quite sure the pictures floating around on here are correct,,
If you HAVE to do this to make it run, it proves there is a problem with your carb
No doubt over the years the internal passages have become restrictive or blocked
No other explanation really

Yes i moved to the darkside

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Also re that link if you block the part throttle lean off ports 3 and 4 on the turbo carb can be considered the same thing unless the float hight is set rather high then 4 can sometimes spit fuel into the pipe work

Edited by Brett on 2nd Feb, 2015.

Yes i moved to the darkside

Instagram @jdm_brett

i was referring to this pic
http://www.turbominis.co.uk/_iain/up/hif_mods.jpg

i had it the way it showed and im sure it was because the number 4 was blocked caused an air lock in the bowl because the jet tube is really low in the bowl and the float is higher up my theroy to what hapend is that the float was down due to not much fuel in the bowl then the seat opens letting fule flow in and at the same time air is pushed out the jet tube untill it becoms covred with fule then the air is compressed slightly as the fuel pushes in and the air is now traped cos number 4 is blocked (4 being the bowl vent) this lest the fuel become under pressure more than enugh to push it out the jet tube but this happends before the bowl can fill enugh to close the seat and stop flow

so as you say brett my float may be set a bit to high

but that said literialy as soon as i un blocked number 4 and let it vent to air it ran just fine and stoped shoteing fuel out the jet tube so that lead me to think it was an air lock

didnt get a chance to run it down the street so not sure it the "T" trick has solved it

as for the carb being blocked internaly i hope not as i compleatly scrubed in inside and out and put a genuwine SU HIF44 turbo kit in it so if its blocked internaly id be suprised alto t may be just that

where is the bowl supost to vent to? or such passage way that the "t" trick is supost to solve?

cheers for the input by the way

think its the balance pipe it vents to when running ok,not blocked.

so barbs 3 and 4 are connected internally?

maybe, i know if the float is incorrectly set or the base fuel pressure is too high, and every port is correctly plumbed up the jet is sometimes the first place you see fuel squirting,


internally these are connected

Yes i moved to the darkside

Instagram @jdm_brett

i see perhaps some dirty mud wasps have gotten in there basterds get in to everything usealy make a good effort to block ports and holes to prevent this tho

still not had a chance to take her for a run working long days