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New SU Fuel Pump - Gas leaking out of carb vents

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J

Jersey

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I replaced my old AH mechanical pump with an electric SU pump from Moss motors that was supposedly compatible with my MK II. After some initial problems with air leaks, the car started easily, but now I see gas dripping out of both of the carb vent pipes.

I assume it too much pressure, but I am looking for advice on on how to step down the pressure or make some simple adjustments to the carbs to prevent the spilling.

Any advice?

Jersey
 
Well the float levels may need adjusting or the needle valves in the float chambers may need replacing because they are worn.--Fwiw--Keoke
 
When was the last time you rebuilt your carbs? I agree that you should check your needles first! And make sure your floats are adjusted properly while you are at it.
 
https://picasaweb.google.com/lh/photo/KOhwD8z0HjsfXGIA6WLt0g?feat=directlink
King Filter can be a better solution for fuel pressure
regulations- you can find more technical info on Chriss Dimock
site www.myaustinhealey.com/
Andrea
here the photo of KF on my AH engine Bay in the function of fuel
pressure regulator(note there are TWO type of KF -the biggest have the possibility to mount a pressure gauge)
https://picasaweb.google.com/lh/photo/HJWqrBODwTk1RTipu7ttXg?feat=directlink
on my MG TD the KF absolved only the PUMP filter protection
 
Filter King is very good but I had a problem with the smaller one. It suffers from the filter bowl being made of plastic so after four or five years it gets compressed by the retaining clamp to such an extent that it won't seal. Get the bigger one with the metal bowl.
There are also modern pressure only regulators available that are quite cheap but don't really look the part in an older car but are small enough to be put out of sight.
 
:iagree: Shake the floats to see if they are retaining fluid. Also, now would be a good time to swap the old needle valves out and install Grose-Jet valves instead. It's an easy swap and an excellent upgrade.
 
My Grose jets would stick closed.
Hard to start with no fuel in the bowl.
Replace your needle valves with the Viton tip needle valves.
Moss has them.
 
My Grose jets would stick closed

OLD Deaign.New design uses two sma;; balls.
----
 
Lots of different opinions regarding Grose Jets. Joe Curto told me to throw them away and go with the Viton tipped needles. IMHO, when it comes to carbs, Joes the man.

Marv J
 
Healeysince59 said:
Lots of different opinions regarding Grose Jets. Joe Curto told me to throw them away and go with the Viton tipped needles. IMHO, when it comes to carbs, Joes the man.

Marv J
Click to expand...
I agree with Joe. The engine vibrates and gas can escape past the grose jets seals. They are solid metal seal against another piece of solid metal. The original needle/seats have a small spring tension in them to stop that. They do however get old and wear out.

I had problems with grose jets in the past and won't use them anymore.
Patrick
 
Moss seems to only offer Grose Jets. Nothing came up when I searched Viton tipped needles on the Moss site?
 
That's it thanks.

I installed Grose Jets in my BN6 about 8 years ago and I must say they did cure the overflow issues I was having. However, I am currently experiencing some sputtering and was wondering if the Grose Jets may be the cause? Is replacing the Grose Jets with Viton tipped needles a straightforward procedure?
 
Installation is straightforward. You may wish to check your floats first. They can fill with fuel and sink.
Even brand new floats can sink, if defective.
Don't ask me how I learned this fact.
(3 carbs = increased chances for misadventure)
 
Sounds like these Viton tipped needles are highly regarded. Have any problems been associated with them? Do they hold up with the new fuels? How long are they good for?
 
Mine work great! No leaks at all and they seem to hold up well with todays fuels. I put them in when rebuilding my HD-8s last year and still holding very tight.
 
drambuie said:
Mine work great! No leaks at all and they seem to hold up well with todays fuels. I put them in when rebuilding my HD-8s last year and still holding very tight.
Click to expand...
Where'd you get them?
Patrick
 
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