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Carb and Fuel line Question


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Just bought a 77 Corolla for a daily driver/commuter. Fuel is leaking out of the inline fuel filter after driving it for a bit. Seems like it is still being pressurized even though the car is off. Filter looks to be relatively new. 
Should there be enough pressure to cause it to leak after the car is turned off? Also it appears to be missing some hoses off of the bottom of the carb. I believe these are vacuum hoses that are missing and causing the car to idle high once at operating temp. Any suggestions on tracking down where the hoses should go?

Your help is appreciated

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I was just about to answer your query, with exactly what Pete has stated.

Rubbers everywhere in the car get hard and brittle when cars get to be 40 years olde !   Go and get 2-3 metres of new carby vacuum hose, & replace the lot, bit by bit.  Take an old one off.  Cut a new one to length & then replace.  Do this systematically.

The fuel pump is between the carby & fuel filter & sucks, not pressurises.  The fuel tank should not be pressurised unless they is a problem with the pressure relief valve for the tank.

Drive car; pull up. Quickly check if filter is leaking. Remove fuel cap quickly & see it leak stops, or reduces.  A close visual of where the fuel filter is leaking should reveal what the problem is.

Lots of pics of the problem areas will assist.

Cheers Banjo

Edited by Banjo
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It may be lightly pressurised if someone has fitted an electric fuel pump, not uncommon, especially if the mech one has failed, but it would be about 5psi maximum, so its not going to be some big residual pressure, as it would be regulated to a low figure and just not retain pressure once the car is off and not pumping any more.  Likely the fuel filter and rubber lines would be a great thing to replace for peace of mind.  Id also suggest dropping the tank and redoing the supply, return and breather hoses, and even cleaning it out as well since it could have 41 years worth of corrosion, dirt or bad fuel inside that will be sub optimal to ingest in the carb.  Maybe even give the carb a dose of carby cleaner and try to make it all as clean as possible, then make sure the idle mixture screw is in the right spot.  Hopefully it runs sweet after this, or you might need to overhaul the carb.  Generally when you buy an old carby vehicle, the carb has gotten choked up with deposits over the years, and it has slowly become more and more asthmatic, as the short term fix is often to just crank up idle air and keep it running at a healthy rpm where it wont stall, instead of addressing the symptoms of a dirty carb directly.

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Things to do/check if it were me in your situation

- Check how they have connected the pipes at the tank. there is a suction an overlflow and a breather. make sure the breather is connected to your carbon canistor. Often when people hook them up they hook them up wrong. sometimes the overflow and breather gets mixed up. 

-carby kit in the carby, its cheap, its tedious, a good saturday afternoon activity. with a beverage of your choice.

-all rubber hose replaced with high pressure fuel hose. its cheap as. I would not bother with the low pressure stuff. High pressure EFI hose all the way. 

-GOOOD hose clamps. The type with the little bolt. you get them from industrial parts mobs, cheap as

-new fuel filter

All up about $80 total. few hrs work.

 

 

 

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