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SU-HD6 Gas Leaks

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Bobbee44

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I may have found the culprit responsible for my too rich running MKI 3000. I smelled gas on Sunday morning and popped the hood to find gas literally running out of the overflow from the front carb float chamber. This was in concert with gas running out of the Auxiliary Enrichment Carburetter Thermo (correct nomenclature). My first guess is two floats not floating...am I close?

Bob
 

MarshgrassA

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Not sure on Healey's but when my MGA did that she needed some new carb stuff and I think it was the floats. Not a good feeling to smell that and see the gas running out of the overflow tube.
 

Keoke

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I would think the Auxiliary Enrichment Carburetter-- Thermo needs a bit of attention.
 

Keith_M

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I may have found the culprit responsible for my too rich running MKI 3000. I smelled gas on Sunday morning and popped the hood to find gas literally running out of the overflow from the front carb float chamber. This was in concert with gas running out of the Auxiliary Enrichment Carburetter Thermo (correct nomenclature). My first guess is two floats not floating...am I close?

Bob

I don't know about Auxillary Enrichment Carburetor, but overflow at the main carb bowl is either a sunk float, a sticking float, or a bad needle valve. Cleaning the needle valve may help if the float isn't sunk.
 

John Turney

Yoda
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I think the Auxiliary Enrichment Carburetter Thermo relies on the fuel bowl of the main carburetor for fuel level, so following Keith's advice should take care of it.
 

coj

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I had a problem with fuel coming out the overflow tubes on the bowls. Did not realize it at first, but the car would cough and spit at higher revs.Thought it was a timing or points issue. I removed the caps on the units, and replaced the needles, it now runs great and no leaks. Word of caution however, some of the new floats do not have enough play, even after being bent to fit. If your old floats are OK use them. My new needles came with a new brass body, and two plastic needles. Easy to change out, but the air filters need to come off.
 
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Bobbee44

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Thanks for all the sage advice. I had a couple of hours this weekend and decided to pull the tops of the float bowls, unscrew the needle seats and clean the needles, seats, floats and float bowls. I noted the float levels seemed a bit high, so I reduced the levels in both by 1/16". The car runs better than it has since I've owned it. This morning, a bit cooler than normal, it started almost before I pushed the start button. The Aux Enrichment Carb kicked in and off per specification. All is well...for a while.
Bob
 
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