Topic: Just POR'd my tank and am worried about the Petcock tube (inside the tank).

[VigCS]

Hi all.

Today I POR 15'd the inside of my tank (what a pain), and I had a #$%* of a time getting the excess sealer out (eventually just said screw it and tilted up the back of the tank so the excess would dry in the front).  Basically, at least with my tank, there's a plastic tube coming up from the petcock with screens in it, and I'm worried they will get clogged when it dries.  I ran some Q tips up in there and got what I could out.  I also tried blowing some compressed air in there and it was fine.

It's a single threaded nut-style petcock.  Is there any way to take this little tube out?  I'm honestly not sure if it was supposed to come out with the petcock assembly or stay in the tank.  There's another plastic tube that runs up inside it attached to the petcock.

Thanks!

[BeSeeingYou]

What bike.  There are a few different types of petcocks.  On the 750F the tubes and the sock filter should come out with the petcock.  Sounds like you may have glued it in permanently but it should still work if the tubes are clear and the filter is not sealed up.

[VigCS]

What bike.  There are a few different types of petcocks.  On the 750F the tubes and the sock filter should come out with the petcock.

Sorry, it's a '78 550K.

[BeSeeingYou]

I took a look at it on a parts diagram at BikeBandit.  While not exactly the same as mine on the 76F it is similar.  At this point as long as you can get the rubber sealing washer out if it needs replacement you may be ok.

 I don't know how it comes apart with the 550 but if the Por 15 has not dried can you get at it from inside with a long screwdriver and push it out?  Not sure if that is a good idea, hopefully someone with a 550 will chime it.

[VigCS]

I took a look at it on a parts diagram at BikeBandit.  While not exactly the same as mine on the 76F it is similar.  At this point as long as you can get the rubber sealing washer out if it needs replacement you may be ok.

 I don't know how it comes apart with the 550 but if the Por 15 has not dried can you get at it from inside with a long screwdriver and push it out?  Not sure if that is a good idea, hopefully someone with a 550 will chime it.

I just went out and took a look, but the tube inside is same inner diameter as the petcock threaded stud's inner diameter, so I'm not sure if it can come out.  The lighter sections are the metal screen.

Here's a pic of what it looks like in the tank.  The standard plastic tube attached to the petcock goes up inside of it:

[BeSeeingYou]

It does look like the filter has been coated.   Maybe the compressed air helped but can you get a small flashlight with a focused beam on that filter to see if it looks like it will pass gas?  The parts diagram shows it as a separate replaceable part along with an O ring called the filter set.

[BeSeeingYou]

I took a look at my old tube minus the filter and what you may be seeing is the base (about 1/4 inch high)of the filter tube which fits inside the petcock and may match the inside diameter of the tank fitting.  Above this base the tube has a slightly smaller diameter (about 3/4 inch high) and this fits up into the tank fitting then it narrows down to the inlet tube and filter.  I know it's not the same but yours might be similar.

[Lars]

the CB 550's came with two different petcock systems. One was connected to the tank with two srews, the other one like yours. After removing the petcock, I think I only used a screwdriwer to get out this filter - working from the petcock side. It is most likely clogged and I would replace it.

Lars

[TwoTired]

The in tank filter does indeed come out on the 78 CB550.  It has a very fine mesh and POR15 will seal the mesh up tight, rendering it useless.  Now that it is glued in, getting it out to clean off the coating without destruction will be very difficult.  It normally just rest on a ledge or step machined in the tank bung/fitting.  If rust hasn't gripped on to it, it simply pulls straight out.  Slightly stubborn ones come out with some gentle coaxing with an easy out bit.
I think you can still get a new one for $40.

Here is a pic of a new one, and a damaged one from a very rusty tank.

[Frostyboy]

I got mine from here. They still show 3 in stock. $22.46 (USD I suppose?)
http://www.davidsilverspares.co.uk/CB550K-1976-USA/part_70857/

[VigCS]

The in tank filter does indeed come out on the 78 CB550.  It has a very fine mesh and POR15 will seal the mesh up tight, rendering it useless.  Now that it is glued in, getting it out to clean off the coating without destruction will be very difficult.  It normally just rest on a ledge or step machined in the tank bung/fitting.  If rust hasn't gripped on to it, it simply pulls straight out.  Slightly stubborn ones come out with some gentle coaxing with an easy out bit.
I think you can still get a new one for $40.

Here is a pic of a new one, and a damaged one from a very rusty tank.

Thanks for the advice guys.  I definitely should have noticed beforehand but live and learn I suppose (only had the bike for a month).  Does it come out through the bottom of the tank?

[Frostyboy]

Does it come out through the bottom of the tank?

Yep, just undo the big nut (r/h thread) and out she comes. The flange at the base of the standpipe busted on mine during disassembly. Had to fish it out like TT said. The nut screws off the petcock as well but is left hand thread, can a bit hard to hold.

[VigCS]

Does it come out through the bottom of the tank?

Yep, just undo the big nut (r/h thread) and out she comes. The flange at the base of the standpipe busted on mine during disassembly. Had to fish it out like TT said. The nut
 screws off the petcock as well, can a bit hard to hold.

Thanks.  Thing is it didn't come out with the petcock so its basically glued in the tank now.  Should be fun to get it out.

[Frostyboy]

If that flange hasn't broken off like mine did, see if you can break it off.
You should then be able to punch what's left into the inside of the tank & then tip it out through the cap hole. The worry will be that your new lining is now going to be flawed.

[VigCS]

If that flange hasn't broken off like mine did, see if you can break it off.
You should then be able to punch what's left into the inside of the tank & then tip it out through the cap hole. The worry will be that your new lining is now going to be flawed.

I'm debating just cutting the filter at its base and adding an inline filter.

[Gordon]

I'm debating just cutting the filter at its base and adding an inline filter.

Awesome!

[TwoTired]

If that flange hasn't broken off like mine did, see if you can break it off.
You should then be able to punch what's left into the inside of the tank & then tip it out through the cap hole. The worry will be that your new lining is now going to be flawed.

I'm debating just cutting the filter at its base and adding an inline filter.

A bit better than nothing, I suppose.  But, keep in mind the fuel line is only fed by gravity pressure.  Any air bubbles or circuitous routing can trap air bubbles in the line that will fight the fuel flow, particularly when the tank is low on fuel. (Air WILL get in there via design of the carb bowl fuel valve.)
Some have had difficulty meeting needs with the short and small area available in the fuel route.  I recall one mention that a right angle type filter made the task less difficult.
I don't know of any inline filters that have the same metric sized nipples that are found on the tank and carbs.  So, you will also have to invent a scheme to adapt different fuel line and different clamps to to the routing.  Keeping screwdriver access to the clamps in the limited should be fun.  Or, distroting the existing metric fuel line onto the inline filter chosen.

You also have to add a note to your routine maintenance schedule to clean or replace the filter periodically.

[eurban]

As you now know when you coat the inside of the tank, the standpipe filter tube should be removed.  When I coat a tank I usually chase the inside of the bung with the correct size drill bit to remove any traces of coating so that the filter tube will slide back in properly.  You should be able to use a correctly sized drill bit to cut out the old filter.  Turn the tank over and look at the threaded bung and you should be able to see where the plastic stand pipe filter meets the metal of the bung's ID.  Find a drill bit with an OD just a hair smaller and run it through the hole.  Clean out the remains of the filter from inside the tank and you should be good to go.  BTW its probably a good idea to replace the filter with a new one as part of the tank refurbish anyways; don't feel too bad!

[TwoTired]

This model has a step or ledge in the bung to keep the filter from falling into the tank.  Don't chose a drill size that removes the step.

[eurban]

Good point TT.  Upon reflection I think that all the models with the standpipe filter have a ledge to stop the filter from pushing in too far.  If you have a drill bit set, just start a bit bigger than the ID of the plastic tube and work your way up progressively.

[VigCS]

Woohoo, got that SOB out:



Nothing a precision flathead, hammer, and pair of needle nosed pliers couldn't handle.  Now to find a new one..

[Stak66]

I had the same issue but was able to remove in the same fashion. Although I had not coated the tank before removal. Question I have is what is the ID of bung hole. And what is the OD of the threads. I have a 75 cb750F that had the same style filter but the new petcock (purchased from Bikebandit.com) has a different style filter and the nut size is too large. As a note, I did use the online microfiche that states what I bought is what I should need. The ID in the tank is 10mm. The OD is 16mm. Anyone have a suggestion of a different petcock that would work. Attached pic shows...left is new petcock. Middle is what was put on there by previous owner. Right is the original petcock (which is not the right size anyway)

[TwoTired]

It would appear you have a tank fro a 77or 78 model.  These fuel valves and filters are different from the earlier models.
I think it is a 5/8" Bung.

You still have the valve?  I think the filter is still available from Honda.
P/N 16952-388-015, ought to get you a new filter.

[BeSeeingYou]

The 75/6 petcock is still available, the one you got, but the 77/8 is not.  Maybe check the for sale section as 77/8 F parts are there often enough.

[Stak66]

Thanks TT. I did a quick search and it does appear that a 77/8 petcock would be correct. Now just to find it. I'll first look in the for sale section as srust suggested.
BTW...I'm a noob and this site is freakin great.