V8 P6 fuel lines

B

BSKPLoft100

Member
A previous owner has fitted an electric fuel pump just under the tank, the pipe then go to a pressure valve cum filter under the bonnet, so from there the usual feed to the carbs.
My question.
Before the feed enters the carbs, a branch off. This I would imagine returns excess petrol to the tank, (being engrossed with the rest of the car refurb, I have not checked,) so, starting up the car, I sometimes have fuel dumped at an alarming rate from the carb overflow pipes.
So back to the branch off, why is this fuel not returning to the tank, if the carb floats have shut of?
There is, in this pipe a visual amount of petrol, about 9" which does not seem to move, blocked??
Please read again before answering
Keep well
Regards
Brian
 
There is (or should be) a restriction in the return pipe to the tank, if your electric pump is flowing too high a volume of fuel at too high a pressure, it won't be able to get through the restrictor, and could then overcome the needle valves, and flood.
 
harveyp6 said:
There is (or should be) a restriction in the return pipe to the tank, if your electric pump is flowing too high a volume of fuel at too high a pressure, it won't be able to get through the restrictor, and could then overcome the needle valves, and flood.
Click to expand...
 
Thanks for the advice, I had a look today at the return pipe, as the fuel exits the tank, it has a "T" piece, of which, is a feed to the fitted electric petrol pump, and an entry for the petrol excess?? It seems the fuel does not return to the tank, but is circulated?
Taking the pipe of the carbs, I find I cannot blow down it, hence the dormant petrol, and probably why the carbs are dumping fuel on my path
regards
Brian
 
Back again people, pipes to tank corroded up. managed to remove and replace with copper.
The restrictor in the return pipe full of tar, (does petrol turn to tar if dormant for years).
Anyway, cleaned out the restrictor, and excess fuel from carbs now flowing OK
So, back to the fact, that this pipe does enter a "T" piece and not directly into the tank, Thus making a circuit back to the carbs, is this the norm?
Any one had this problem?
 
The pics in the parts book show the return going into a T type fitting at the tank outlet underneath, so I think its normal. Probably done to avaoid having another pipe into the tank - the area getting a bit crowded with fittings. It would have been messy to run a pipe into the top of the tank given its design. Your observation makes me wonder about checking my return line is clear.
 
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