Fuel won't stop dripping from overflow tube

[Lynn]

Hi, need a little help w/ fuel coming from my overflow. Searched quite a bit and didn't find anything on this.

'94 MX7 180B, O-360C1F, 350 total time, long range tanks (empty), otherwise standard. I've got 100 hours in the plane w/ no flaws at all. After an avionics upgrade including a gps antenna mounted to the left wing, I put the plane back in the hangar only to find a drip coming from the plastic overflow tube at left rear of cowl. I verified it's coming out of the tube and not somehow draining down the tube on the outside. 1 drop of fuel every 3 minutes or so. I inspected everything and flew the plane without issue thinking it was pressure / weather related and would quit. It didn't.

Shutting the fuel off doesn't stop it. No abnormalities noted with fuel pump. In flight I use a combination of L, R, and Both, and nearly always hangar the plane w/ selector on both. It's never leaked.

The avionics shop is highly reputable so I'm leaning toward coincidence but who knows. Any ideas?

Thanks.

[vaughans]

Hi,

Sounds like the seal in the Dukes electric fuel pump is weeping, not uncommon and usually indicates time for rebuild. CJ Aviation in Florida has done a good job for me before.

vaughans

[a64pilot]

Hi,

Sounds like the seal in the Dukes electric fuel pump is weeping, not uncommon and usually indicates time for rebuild. CJ Aviation in Florida has done a good job for me before.

vaughans

Yep, that's it. David Wright keeps the seal in stock as it's pretty common, but it's not real easy to install, you might want to send it to him once you price a re-built pump.
Has nothing to do with the avionics shop.

[MauleWacko]

[Hogy59]

I have the same plane (year and model). Mine did the same thing, but when I shut the fuel valve off, it would stop. I played with it for a while, then started checking out options. One option, the one I chose, was to do the Autogas STC. It does away with the Dukes fuel pump. I think it was a little over a grand for the parts from Maule.

[210TC]

Send it to the Dukes factory in California for a certified rebuild. It is worth the notation in your log book. You will now have a certified rebuild that will most likely last 10 plus more years. My first lasted more than 20 years.

[Green Hornet]

I had the same issue some time back. I have attached a link to the thread on this site: I agree with David on a rebuild but I got done cheaper by the company in the thread below.

http://maulepilots.org/forums/viewtopic ... ight=dukes

note: That the dukes fuel boost pump has a 10 year inspection rebuild date code.

[Lynn]

I appreciate the quick responses and diagnosis. Thanks!!