Fuel Pump O-Rings

[DaV8or]

Does anyone know where to buy these O-rings? These fittings go on the electric boost pump. I have the Weldon pump. It's a two part ring seal with an outer leather, or fiber looking ring and an inner rubber ring.

Thanks for the help. 

[carusoam]

Hey, a real DaV8or sighting!  

I haven’t seen that seal...  see if @M20Doc knows that seal...

Great pic Dave.

Best regards,

-a-

 

[Guest]

If it’s a standard -6 fuel line(with 11/16 line nuts) then it should be a MS29512-6 “O” ring.

Clarence

[DaV8or]

3 hours ago, M20Doc said:

If it’s a standard -6 fuel line(with 11/16 line nuts) then it should be a MS29512-6 “O” ring.

Clarence

Interesting. It does have 11/16 nuts on it. There is a recess cut in the nut as well the threads. The two rings in the picture are locked into the recess in the threads. Have you ever seen this two ring composite before? Is possible that it should just be a single rubber O-ring as you are maybe suggesting? I'm wondering if these rings and the fittings came with the Weldon pump as part of the replacement kit for the Dukes pump?

[Guest]

1 hour ago, DaV8or said:

Interesting. It does have 11/16 nuts on it. There is a recess cut in the nut as well the threads. The two rings in the picture are locked into the recess in the threads. Have you ever seen this two ring composite before? Is possible that it should just be a single rubber O-ring as you are maybe suggesting? I'm wondering if these rings and the fittings came with the Weldon pump as part of the replacement kit for the Dukes pump?

The leather backup ring is used in some designs, not so much anymore.  If the leather is used, the face of the nut has a counterbore to receive it.  Newer designs use a regular nut and “O” ring which fits the chamfer in the pump body.

Clarence

[carusoam]

When it comes to O-rings...

Make sure you opt for one that is approved by the pump people for use with 100LL... (as Doc has pointed out above)

Based on our collective experience with O-rings and fuel caps... standard O-rings have a tendency to swell and not fit over time...

Thanks Doc! 

Best regards,

-a-

[DaV8or]

13 hours ago, M20Doc said:

The leather backup ring is used in some designs, not so much anymore.  If the leather is used, the face of the nut has a counterbore to receive it.  Newer designs use a regular nut and “O” ring which fits the chamfer in the pump body.

Clarence

This is the older style. The pump has flat faces and the nuts on the fittings have the counterbore to fit the leather ring. Is there somewhere to buy new leather rings and rubber O-rings?

[Guest]

5 hours ago, DaV8or said:

This is the older style. The pump has flat faces and the nuts on the fittings have the counterbore to fit the leather ring. Is there somewhere to buy new leather rings and rubber O-rings?

From the IPC, item 13 has numbers for both. If the leather is in good shape you can likely re use it.  A few drops of oil on the O ring and the leather would be good.

Clarence 

[DaV8or]

2 hours ago, M20Doc said:

From the IPC, item 13 has numbers for both. If the leather is in good shape you can likely re use it.  A few drops of oil on the O ring and the leather would be good.

Clarence 

 

Thanks for the info. However I checked my fitting again and I was mistaken, the nut takes a 13/16 wrench, not 11/16. I guess this one is bigger then?

[Guest]

58 minutes ago, DaV8or said:

Thanks for the info. However I checked my fitting again and I was mistaken, the nut takes a 13/16 wrench, not 11/16. I guess this one is bigger then?

The check nut for a -6(3/8”) fitting should be 13/16”, the “B” nut on the 3/8” aluminum line should be 11/16”

Clarence

[DaV8or]

24 minutes ago, M20Doc said:

The check nut for a -6(3/8”) fitting should be 13/16”, the “B” nut on the 3/8” aluminum line should be 11/16”

Clarence

The nut on this one has "AN" stamped on one flat, "TF" stamped on another and "D" stamped on a third. No -6.

[Ivan]

On 1/26/2020 at 7:29 PM, DaV8or said:

The nut on this one has "AN" stamped on one flat, "TF" stamped on another and "D" stamped on a third. No -6.

@DaV8or were you able to find O Ring eventually?

facing the same question right now. M83248/1-906 which i got from the shop, does not seem like the right one

[carusoam]

Hmmmmmmm….

DaV8 came by earlier…. But isn’t writing very much lately….

Stand by… see if he shows. 

Best regards,

-a-