How do I rebuild Mr. Petcock?

[dchakrab]

Ok, so now I'm ready to begin. Igor's raised the lightning rod, and we're waiting for a storm, and then petcockkenstein should be lurching off the stretcher and onto the highway.

I have two '82 rebuild kits from Sirius Consolidated. I have sprayon carb cleaner, which my metal parts have been soaked and polished with. I have engine oil, which my old rubber parts have been soaking in overnight. I have two inline fuel valves, as well.

So, the 82 rubber thingies look like they'll fit in place of the two similar thingies in the 83, assuming I can figure out how to get them in there. The 83, however, has two (valves?) set on a rubber sheet. How do I get the two 82 valves on the 83 sheet...just cut out the old ones and glue in the new ones? What kind of glue should I use?

Second...how do I put all of this together?

Third...which line goes where when I put this back on my fuel tank? I have a bunch of connections coming out of the petcock, and a bunch of hoses around where the petcock used to live, and no idea what goes where. I also noticed one of the hoses was stopped off with a plug...i assume this is the vaccuum line, which is also plugged on the petcock? Should i unplug and reconnect, or does this not matter?

All help appreciated. Will post pictures and a how-to guide if I'm successful.

  -Dave.

[h2olawyer]

Igor's raised the lightning rod, and we're waiting for a storm, and then petcockkenstein should be lurching off the stretcher and onto the highway.

;D "Elevate me."  ;D

Dave - Wish I could help you out, but I've only looked at an 83 petcock externally, from a distance.  Good luck & I'm sure somebody here will answer your questions!

H2O

[Superfly]

Usually, they go back together the same way they came apart! ?;D

Make sure that you align the dimples on the plastic piece with the holes in the diaphrams, and they align with the holes in the petcock cases. ?I had one that someone did not line those up, and smashed the little dimples, and the springs go on the outside of the petcock, next to the case.

[ProfessorRex]

I could be wrong, but I don't think anyone has done an '83 petcock rebuild!  You're breaking new ground!

-Rex

[Dave]

Now you tell me.

Ok...will butcher and post back with pictures tomorrow sometime, I suppose. It's supposed to rain in Chicago for a few days, so I'll have some time to sit at home and tinker, though not much time to take it out to the bike and test each time.

Worst case: Could I just seal the outer rim of the petcock assembly permanently or semipermanently, so stop the gas leak, and lock in an always-on position, and just use my flow valves to control fuel flow to the carbs?

  -Dave.

[louthepou]

ah Ha, I beg to differ!

Superfly will soon recieve a nice clean 83 petcock, I just disassembled, cleaned and reassembled it.

Don't worry it's not that bad.

Essentially, you want to:

1. remove the inlet filters, the two tubes that stick upward in the tank. They should come off by prying them off with your fingers.

2. Notice the orientation of the plate that's got a few inscriptions on it, it's held by 6 screws, it need to go back in the same way, not turned 180 degrees. There's a small hole in the plastic plate that needs to match a hole in that plate and a thingy in the other metal side of the petcock. Wow that sounds weird, look at the petcock it may make more sense.

3. Any time you remove a metal plate that's touching a rubber diaphragm, you go slowly, with a small flat head screwdriver, to make sure the diaphragm lets go gradually, not to rip it appart. Unless you have spare parts or new parts, of course; I didn't have that luxury. You need to be really careful, especially with the smaller section (plate held by four small screws). Be careful not to loose any spring or other small part. Work over a large clean piece of fabric.

4. Metal parts need to be clean, I use carb cleaner and a dremel with metal brush. Rubber parts need to be clean, remove them from metal parts first, then use a bit of oil. Like engine oil, or I use "power steering stop leak" oil, because I happen to have a few onces left.

5. You put things back together, making sure the parts are oriented in the same way as before when the possibility of a mistake is there.

6. That's all I can think about but feel free to e-mail me if you're confused, and don't worry it's feasible.

Louis

[dchakrab]

This sounds like a great place to start...thanks!

However, I also have two '82 petcock rebuild kits (new) which I'd like to use to rebuild the '83 petcock...it's been hinted that this is possible on other threads in this forum, but no one seems to have actually done it themselves. I'm unsure how to use the new parts I have to replace their not-so-clearly-matching counterparts from the petcock...for example, each kit has one rubber piece (diaphragm?) with a metal round piece in the centre, and my '83 petcock has two of these. However, on the '83, both seem to sit on one piece of rubber...what do I do with the two individual  ones from the kits? Glue them onto the same piece of rubber, after cutting out the old ones, or...?

  -Dave.

[louthepou]

Hi Dave,

I'll send you an e-mail, we'll chat that way - I may need a few pictures from you to better articulate my thoughts.

Lou

[Lucky]

the metal center pieces of the diaphrams are pressed together. you cant cut & glue them, it won't work, won't seal..
I believe what James Ransom was suggesting (i think he said he's done it) is to use the two single diaphrams in place of the one double 83, by overlaping them.

[dchakrab]

It doesn't look like the two '82 diaphragms are large enough to overlap on the 83 base...and the only way to remove the '83 diaphragms from the base seems to be to cut them down the middle, and push them through...?

I'll post pictures sometime tomorrow, so this is clearer, and you guys know what I mean...not knowing the names of the parts inside this petcock is making it hard for me to describe/explain/understand.

Thanks,

  Dave.

[louthepou]

I do believe that if they just sit side by side, the two will do a good job at replacing the double 83 one. You've got to think about this in terms of what they do and where the gas is/goes, that's my humble early sunday morning Jedi wisdom. More precise down to Earth advice once pics are here,

Louis

[dchakrab]

If young Jedi knew what they did and where the gas is/goes (other than all over the place) this would certainly be highly simplified.

I *think* the diaphragm things are built so the springs hold them closed, and no fuel goes through, except when there's a vaccuum, which pulls the diaphragms out, so the little plug/valve things in the centres move out of their sockets, and fuel can move through. Then, somehow, it ends up in the fuel outlet from the petcock, which I think is the bottom-most tube. But if this is right, then it wouldn't work without the vaccuum tube at all, since the petcock would always be closed?

  -Dave.

[Lucky]

correct except the 'Prime' position bypasses the vac valve, it flows fuel all the time.

In case it was never mentioned to you, "on" & "res" are only supposed to pass fuel when there is vacuume applied (engine cranking/running). that's why there is no 'off' position.

[dchakrab]

Here are the images, as large as I could take them. Excuse the lack of focus...I've been drinking beer and trying to figure this out since the morning, and I don't think this camera will focus that close, so it's a little blurry.

So I think what I should do now is cut the rubber thing down the middle, and push the two parts through their respective holes in the plastic plate, and remove them, and then replace them with the two new parts from the kids. Is that it? Then I just reassemble and test?

Everything's soaked in oil at the moment, and the rubbers are curling a lot. I don't have a dremmel, so I haven't done a perfect cleaning job...just used carb cleaner and wiped everything off as well as I could.

Where do the springs go...?

  -Dave.

[dchakrab]

I think my pictures scared you guys off...is it that bad, or are the boards just slower on a Sunday? Come on guys...I'm sitting here with my scissors wondering if I'm going to regret it if I go ahead and cut this thing without Lucky's written permission...

  -Dave.

[dchakrab]

Ok, couldn't take it anymore...it's a beautiful day, and my bike needs to run!

I went ahead and cut the old diaphragms out, since I couldn't think of a way to get them off the plastic plate otherwise.

Here's where I am now:



The ones from the rebuild kit seem too small to work here...they're not even large enough to cover the round depressions in the plastic.

I'm going to go ahead and put them in, and see how it goes. I'm putting the petcock back together again (or trying to) now...let me know what you guys think.

  -Dave.

[louthepou]

Sorry about the delay Dave, I've been out all day. (No, not on my bike, but building stairs outside my sister's house).

The diaphragm from an 82 should fit, side by side, at least that's what I think. Don't get mixed up with the diaphragm that goes in the little part held in place by 4 screws.

Tell us how it went, I'll try to come up with clearer explanations (in a bit of a rush at the moment)

Louis

[dchakrab]

Argh. Finished everything, got all hopeful, and realised i can't find the two screws that hold the petcock to the tank. Went to Ace Hardware, got two screws, came home, they don't fit...they're just a hair too small to hold in the threads, though they go through the petcock holes just fine.

Now off to Murray's, which will hopefully have screws.

Will post back if I manage to get this thing on today.

  -Dave.

[dchakrab]

Fate doesn't seem to want me riding today, at any rate. Everything's closed, even the Murray's that has a 24 hour sign out front. For those 2 screws, it looks like I'm going to have to wait another day. I'll have to go hunting for screws tomorrow morning, I guess.

:(

  -Dave.

[Coil Coyle]

Dave,
I'm getting worried now. I am sure that when I first found this site and followed some of the links that I read a procedure to use two 82 kits to fix an 83.
By your pictures I just don't see how it could work.
I have two kits coming based on the post I read somewhere. I specifically remember the author wrote that during assembly the overlap of the diaphrams should be coated with
"silicone grease, NOT Silicone sealer. Silicone sealer will ...(something bad)"
My prayers are with you, I'm right behind you on the same path. :-/
coil