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Carburetor Banjo Seals

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joe948

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I am having a heck of a time with the banjo seal on a 65 BJ8. Covers were off and now can't get new fiber gaskets to seal, recessed area on outside.
Cleaned up the fittings and hate to go too much more to tighten. Do they need time to form or set up?
Seems like they go a little more after sitting. Any tips? Use sealer? Thanks in advance.
 
The original fibre washers were intended to be soaked in kerosene for a time before use. I'm not sure that the new ones are the same material but would be worth a try.

Danny
 
Agree on soaking; not having kerosene handy I use WD40 (gasoline would work too). There are RTV/silicone sealants that claim 'fuel resistant;' a very thin coat might help/wouldn't hurt (I've used it elsewhere). I'm not sure what 'recessed on outside' means; newer few pumps, which used to use the same fiber washers on flat sealing surfaces now come with O-rings that sit in a recessed bevel on the inside of the sealing surfaces. Note OEM/earlier fiber washers were brownish in color, modern ones are usually black and (possibly) thicker; I'm not sure they work as well as the original. Both types deform after installation; you usually have to tighten the banjos up after they've been in use for a while.
 
Honestly, the fiber washers are a joke - presoaked in kero or mineral oil or whatever. Many years ago (think 40) when I mounted triple SU's on our XKE, I tapered the sealing face of the banjos with a 45 degree tapered grinding stone in a drill press. I then installed them with "O" rings that were compatible with gasoline - take your pick - > O-Ring Compatibility Chemical Resistance Chart <. They don't leak. And they last like forever.
 
Maybe I've been lucky but I have never had a problem with any of the fiber seals beyond their occasionally needing a little more tightening. I do, however, like Stephen's idea of replacing them with O-rings and wonder which one he used for what I must assume is "gasahol". The chart seems to suggest nitrile.
 
Funny - nitrile has been my choice for gasket materials for a very long time. When reformulated fuels were destroying the kits for SU's I made up new diaphrams for SU's - and they are still there now.
 
The seals tighten up more after sitting over night, seems to be finally slowing down. The new seals were a red brownish color from a small gasket set. By recessed I meant the side of the banjo fitting the bolt goes in. This all began with starting hard, cleaned up the needle valves but still getting gas out the overflow. Still a needle problem? Do I need new needles? Car will stumble but not catch. Always been fine before.
Thanks for the response.
 
joe948 said:
The seals tighten up more after sitting over night, seems to be finally slowing down. The new seals were a red brownish color from a small gasket set. By recessed I meant the side of the banjo fitting the bolt goes in. This all began with starting hard, cleaned up the needle valves but still getting gas out the overflow. Still a needle problem? Do I need new needles? Car will stumble but not catch. Always been fine before.
Thanks for the response.
Click to expand...
If you are getting fuel out of the overflow, it's the float level or the float valves that are leaking. Fuel level normally doesn't come to where the banjo bolt washers are when not moving. When the car is moving, fuel in the bowls will slosh around.
 
I had a similar problem when I replaced the fuel lines to the carbs in my BJ8. Turned out I needed to flip the rear carb banjo over 180 degrees. I had the recessed side toward the carb which seemed logical.....NOT. It kept leaking after soaking, etc. until I flipped it over. The forward carb has a different banjo fitting so it did not leak.
 
joe948 said:
I am having a heck of a time with the banjo seal on a 65 BJ8. Covers were off and now can't get new fiber gaskets to seal, recessed area on outside.
Cleaned up the fittings and hate to go too much more to tighten. Do they need time to form or set up?
Seems like they go a little more after sitting. Any tips? Use sealer? Thanks in advance.
Click to expand...
 

Attachments

  • SEAL WASHER ASSY ON BANJO.pdf
    1.7 MB · Views: 114
  • Hly banjo seal washers...pdf
    71.6 KB · Views: 131
I don't think I have ever seen a set of banjo fitting on the fuel lines going to carbs that did not show evidence of seeping. Hence my use of nitrile O rings. Not that hard to taper the seats on the banjo's and a permanent solution.

Just my 2 cents, which is now worth perhaps a Mexican peso, if that.
 
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