Petcock Time!

[Bladedog]

Ok, got all the parts and since we're in for a WET saturday morning,  are there any suggestions as to what else I should check/lube/tweak/tighten/ while I have the tank off?  Already have a fresh K & N filter installed.  Maybe check/replace vac lines?

[hardhead]

Definitely do check your vaccum lines.  I'm in the process of installing an Audiovox cruise control and found one collapsed vaccum line and a couple more that were beginning to crack.  The bike was running fine but I replaced all the lines anyway.

[98valk]

If re-doing the oem unit, install a 1/8" npt snubber in the vacuum line to the petcock. The diaphragm will then take a very long time to wear out.

[John U.]

If re-doing the oem unit, install a 1/8" npt snubber in the vacuum line to the petcock. The diaphragm will then take a very long time to wear out.

Could you help us dummies understand what a snubber is. I'm thinking it's a vacume reduction device like a small orfice jet but I'd like to hear more about it. Thanks in  advance

[rmrc51]

Hope you have better luck then I did.

I rebuilt mine and had a slow leak afterward. Tried a 2nd time with the same results. Now I just ordered a Pingel to replace the petcock and do away with the vacuum.

[98valk]

If re-doing the oem unit, install a 1/8" npt snubber in the vacuum line to the petcock. The diaphragm will then take a very long time to wear out.

Could you help us dummies understand what a snubber is. I'm thinking it's a vacume reduction device like a small orfice jet but I'd like to hear more about it. Thanks in  advance

it doesn't reduce vacuum it reduces pulsations. one type is of the orifice type, however I used the type that has perforated disc of .5 microns, which is for extreme pulsations. Using a mity-vac it would take aprrox 3 seconds for the vacuum to bleed down thereby allowing the petcock to close. The bike has not been running right for the past 4k, (20k on bike now) miles, I kept thinking it was all the carb and airbox mods and ethanol gas was causing the problems while I was trying to dial in the carbs. Here all along it was the vacuum diaphram that was leaking causing intermitent lean conditions. Using my background in LP air systems I remembered about snubbers and how they are used to protect gages from pulsations in the line. Mcmaster carr has a 1/8" snubber $8 and brass fittings, total $$ was $14.  Bike now runs like it use to with the rebuilt petcock.

[John U.]

Many thanks  CA ExhaustCoatings for the info and source. This is the first new (to me) idea I have heard that might help mitigate petcock troubles, and their terrible consequences. Do you think there is any need for the stainless snubber? I guess I can find the hose barbs to hook it up locally.
So where in South Jersey are you? I'm in Lower Delaware. Let me know if you're heading my way.

John

[98valk]

Many thanks  CA ExhaustCoatings for the info and source. This is the first new (to me) idea I have heard that might help mitigate petcock troubles, and their terrible consequences. Do you think there is any need for the stainless snubber? I guess I can find the hose barbs to hook it up locally.
So where in South Jersey are you? I'm in Lower Delaware. Let me know if you're heading my way.

John

Brass is fine, that is what I used. Install it with the disc towards the intake manifold. I installed it 3-4" from the manifold connection just under the carbs. I secured it to the carb support bracket.
http://www.chemiquipproducts.com/  download the catolog.
Finding a female 1/8" hose barb is the hard part to find. mc'master has both.  http://www.mcmaster.com/#44555k123/=1qq4na   $2.51
http://www.mcmaster.com/#44555k128/=1qq4y9   $8.69  snubber .5 micron disc http://www.mcmaster.com/#4034k11/=1qq5ag   $1.00
  I'm east of phila.

[Ricky-D]

You ought to go ahead and do a de-smog while your at it. Get rid of all that extraneous vacuum stuff sitting on top of the motor. if you were to combine a Pingel petcock with a de-smog there would no longer be any vacuum lines to any carburetor, and finally,  relieve you of all the related worries and aggravation that would occur in the future.

[Bladedog]

De-smog is definitely on my list of things I want to do (partly because I know it's an improvement, and partly because it's almost free!) but I am putting it off uuntil I can get some direct help from another well-informed Valker, maybe someone in SoCal.

Petcock rebuild went smooth- no more dribbling gas while the hoses are off!

Thanks folks!

[BigMac (SoCal)]

I can help you with any questions about the desmog. The Shop Talk page will tell you whats involved. California is trying to send some legislation through to smog any motorcycles 2000 year and later. I believe you already have my email address. Shoot me an email and I'll give you my phone no. I've done 5 or 6 desmogs.

Dave 

[Bladedog]

Dave- will definitely be in touch soon.  I'm sure I'll be driving you nuts with questions on the Virginia City trip.  See you then!

[BigMac (SoCal)]

Great, looking forward to meeting you.