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fuel system-I surender

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reddsprite

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When I got my sprite,it had a intermittant fuel delivery problem with a low end electric pump-with no pressure regulator-so I bought another pump and same thing,it runs fine then all of a sudden it starts sputtering like its running out of gas.At this time I said enough is enough.
I had a reputable britcar shop go thru the carbs,and he replaced throttle discs (removed the poppet valve discs and used new old style plain discs and spindles) and tuned it up to specs.
Shotly there after it started doing the same thing,so I bought a SU 1307 pump with banjo fittings on inlet and outlet and have a low pressure regulator set at 2.6 lbs. Yesterday it was a nice day so I put the top down and GF and I went to the marina for lunch-everythings fine.On the way home it started acting like it was running out of fuel,so I put 2 gal of fuel in it and it went back to running fine-I am confused!
rebuilt carbs,pump,filter-does anybody have any suggestions.
It was timed with a high end adjustable timing light every thing is up to snuff. good vacuum,good fuel,recent tuneup and I need to get this right for a tour coming up! Any help would be appreciated-
 
Sounds like you have a rust type break in the line from the bottom of the tank to the fuel pump. Somewhere in that part of the line is a hole where air is getting in and therefore no fuel.
It could be something as simple as a loose fitting at the tank.
BillM
 
Agree with above. Also, blow back and see if there is a clog in the tank pickup.

My latest " red rat " Spridget ran like that. Turned out to be lots of rust in the fuel tank.
I had a spare second tank, but it was also a but grubby, so I cleaned it out and used a modified fuel pickup that left the last 2" in the tank.
Seems fine now (but I will run out of gas sooner).
grin.gif
 
I was about to say rust in the tank, too. Adding gas fixed it, so it probably stirred things up enough that the rust clog was temporarily removed. Do you see rust particles in the float bowls, or in the fuel filter, if you have one?
 
If it runs fine with a full tank and begins to act up at a 1/2 tank it's most likely an air leak at the fuel line coming from the tank. That line has a bullet like end piece to seat into the pickup tube. Any rust in that connection will not let the bullet seat properly. Another possibility is the compression nut that secures the fuel line in the tank has an air leak. When you added gas was it at or below a 1/2 tank? Or was it lower? If it was less than a 1/2 tank and with 2 gallons of gas added still less than 1/2 tank then rust or something is clogging the pickup.
 
Is it sputttering to a stop? Complete starvation?
Although I'd agree to look for crude in the float-bowls, what about the possibility that you have a single float problem and THAT carb is briefly flooding?
 
Fighting this in the Jav as I speak. Start stern to stem and work your way up. I agree with all above. Pull the tank, drain fuel in clean bucket. Inspect drained fuel and inside of tank. Inspect line both inside and out for rust. Clean if you can, replace as nessisary.
 
Thanks one and all-carbs have been gone through-today I took the inlet filter off and cut it open and didnt see much at all -no rust or dirt to speak of.
The only thing that I havent done is drop the tank out of it and go through this drill. When we took off from the restaurant it was fine -then 3 miles down the road it starts sputtering and running really rough-made it to a gas station managed to put roughly 2 gal ($10) in it and it ran successfully home. One final note-during the winter I don't drive it at all-this car went thru a serious restoration,so once a week I have been going out and starting the car warming it up on jackstands and it runs fine in the shop.
Once again,thanks
 
Could you perhaps have gasohol that has condensed water that is floating on the fuel? As you drive, it lowers the good fuel level until it starts to pick up the water layer floating on top. Putting fresh fuel into the tank raises the water level and it runs until it burns down to the bad fuel again.

When you put fresh gas into the car, does it run rough for a little bit and then clear and run fine? Or does it immediately start up and run perfectly? If the first, then it could be clearing the watery fuel in the fuel line and float bowls and then settling down and running fine on the clean new gas.
 
Westfield_XI said:
Could you perhaps have gasohol that has condensed water that is floating on the fuel? As you drive, it lowers the good fuel level until it starts to pick up the water layer floating on top. Putting fresh fuel into the tank raises the water level and it runs until it burns down to the bad fuel again.
Click to expand...

If that is the case, you can get any number of products at Aurozone that are winter gas additives - that essentially deal with the moisture.
 
I had fuel in the boart that was almost 4 years old and it ran great. (non ethanol) I put two cans of seafoam to 33 gallons that were 1 1/2 year old then put two cans of B12 two years later to the remaining 15 gallons.

rop the tank and find out for sure. My uncle had a super beetle that drove him nuts doing the same thing. One of the rubber nipples that keep the cap door from touching the body fell down into the tank. It would vibrate around till it found it's way into the end of the pickup tube and shut the fuel off
 
Sealed or vented gas cap?
You will get similar results with the wrong type gas cap.
Guess how I know?
 
replaced the vented gas cap with a new one was the first solution I tried-
HS2 carbs are filling just fine,it runs great and then it starts acting like it has run out of gas when I know its not. This car went through a total restoration by the previous owner (new paint,interior,guages,trans,engine with 110 miles on it when I got it,everything has been gone through) and was driven very infrequently as he had a host of other british cars at one stage of restoration or another. At this point I have tried every cheap fix there is, I am at the point now where I am going to just bite the bullet and purchase a new tank that is treated for corrosion and rust-I (we) have a big Healey event up in Canada coming up and I dont want to miss it because of the uncertainty of this fuel delivery problem. When the car is dead cold it starts and runs great,the stumble occurs after it has been run for a while,with a load on it.Runs great in my shop on jackstands! In my area the gasoline available is a 92 octane unleaded unless I want to spend $10 a gallon on leaded race fuel
 
Have you confirmed you have 12v at the pump with a multimeter?
What if you turned the regulator up to 3lbs and tried that?
 
Have you eliminated the condenser from the equation, ditto the coil?
 
I had a bad fuel pump that gave exactly those symtoms. Drove me nuts till I eliminated it by trial and error.

Kurt.
 
I bought a SU pump that is actually for a MGB (AUD 1307) its had very little use,it shows 2.6 lbs after regulator . It's practically brand new. I have a spare Facet little cube pump that I may resort to if I cant straighten this out soon....1/3 the money and has a filter before the pump,not just the one that is at the front carb inlet
 
I once bought brand spanking new Lucas ignition parts from TRF for my Spitfre that included a bad set of points. But it would not fire at all. And the quality of some new parts is questionable (ie rotors).
 
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