I have a damaged (hole) in the filter of the petcock. Unable to find a replacement of the filter (I tried Bikerbandit.com and Powersedge.com) I decided to replace the petcock. Since most petcoks do not fit ( the filters are usually round and larger) I will have to make adjustments to the tank. Also, the vacuum line is eliminated. I assume I just plug up the connect to the carburator (?). Has anyone tried this? What brand/model petcock did you use and how was it installed? Will it work by just plugging off the vacuum line? I am at a loss as to what to do. Thanks for any help
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petcock replacement
- Thread starter badgertom
- Start date
hardtailed77
Never Finished
I heard somewhere that the 650 petcock that Mikes sells fits the 400. Maybe Travis or Drewpy could give you a straight answer though.
CadXS
XS400 Addict
If you want to replace the petcock completely you can get blanking plates so you can fit the simpler gravity fed petcocks with 3/8" NPT.
http://www.partsnmore.com/parts/yamaha/xs400/?filters[model]=xs400s
If anybody is feeling helpful they could post me one of these blanking plates...the site above quoted me $65 to send a $6 part to the UK...
http://www.partsnmore.com/parts/yamaha/xs400/?filters[model]=xs400s
If anybody is feeling helpful they could post me one of these blanking plates...the site above quoted me $65 to send a $6 part to the UK...
I'm about 80% sure that the petcocks from MikesXS will work. Don't hate me if I'm wrong though! I have them on my XS650s and SR500. They seem to be somewhat universal for Yamahas of that era. If you get a non-vacuum petcock, just cap off the vacuum port on the intakes and turn the petcock to off when you're done riding.
MikesXS also sells the replacement screens that might work if that's all you need. They are individual screens that go on each tube.
MikesXS also sells the replacement screens that might work if that's all you need. They are individual screens that go on each tube.
Pawl
Arctic chop & bob
Took a dripping xs400 petcock apart last summer, and over frosty beverages we took it all apart and figured out the zany contraption. I seems they work on vacuum to "open" the fuel flow, so turning over the motor, creates suction, allowing the fuel to flow . . . no engine turney over . . . no gassy flowwy! Just pull the fuel line off the carb with fuel in the tank and see if you get doused? We didn't. So simply plugging off the vacuum line could lead to a no gas flow situation.
they are good when they work and I rebuilt mine from a kit from parts'n more than 4 years ago and its still going strong.
I'm using the manual petcock with plate from Parts-N-More. If I can't remember to turn the gas on...or off, I need to pick another hobby.
CadXS
XS400 Addict
Houghmade, this is the set up I'm after to feed a single Keihin carb in a 2-1 system. How is it working? Does the plate seal to the tank ok? Still can't believe Parts-N-More want $65 to send the plate to the UK...bastards, lol.
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It works perfectly. The petcock comes with 2 or 3 hose barbs that can go in one of 2 places, so there are some options for running the fuel line. The plate is thick, strong and fits perfectly- no leaks ever...pity it costs so much for you. At $36 here (when I bought it) it made more sense to me than taking a chance on a rebuild kit that may or may not work (my petcock was "properly knackered" as you might say).
gentlemanjim
More Wrenchin than Ridin
Mikes XS are different the Partsnmore is a great source thanks CADXS.
If I had seen the Mikes XS petcock before the Parts-N-More, I may have gone for that. It looks good and is one piece rather than a plate and petcock. That being said, I'll stick to what I have now.
BTW- I removed the screen from the petcock inside the tank and now I run a replaceable (glass and chromed steel) fuel filter outside the tank.
BTW- I removed the screen from the petcock inside the tank and now I run a replaceable (glass and chromed steel) fuel filter outside the tank.
corona36
Amateur Restorer
Ok, first post. I have a 1981 XS400H. Tried to test out the seals for my petcock. Didnt go too well. Gasket is terrible, the aluminum where the filter attaches to the petcock has apparently turned to putty. Didnt even know that could happen. I'm going to just replace the thing altogether. Now my question is, which one do I need?
On MikesXS I see Part# 20-0019. That looks right. But wait... On PartsNMore, what the hell are all those things... Which one do I need, oh god, brain explosion
!!!!!
Ok, I'm ok again.
So which one should I go with, so lost right now. Thanks in advance for the help.
On MikesXS I see Part# 20-0019. That looks right. But wait... On PartsNMore, what the hell are all those things... Which one do I need, oh god, brain explosion
!!!!!Ok, I'm ok again.
So which one should I go with, so lost right now. Thanks in advance for the help.
akronevan2
XS400 Enthusiast
Keep me posted, I should rebuild my petcock too.
hmusket
XS400 Addict
Since you have to replace your petcock you won't go wrong choosing a manual petcock. The one from MikesXS seems to be the easiest bolt on choice.
Yep, I wouldn't go back to a vacuum petcock.
akronevan2
XS400 Enthusiast
Why wouldn't you?
corona36
Amateur Restorer
Ok, so MikesXS is out of stock. If I do order from partsnmore which parts do I need?
Definately the Universal Fuel Petcock, but which Petcock Adaptor Plate would I need seeing as they list 3 on there? Would I also need the Fuel Petcock Adaptor Nut since there are 2 listed there?
It would be so much easier if there were some in stock at MikesXS, but since I want to get this thing running ASAP I'm going to need to go with partsnmore. I just dont know which parts I need.
Definately the Universal Fuel Petcock, but which Petcock Adaptor Plate would I need seeing as they list 3 on there? Would I also need the Fuel Petcock Adaptor Nut since there are 2 listed there?
It would be so much easier if there were some in stock at MikesXS, but since I want to get this thing running ASAP I'm going to need to go with partsnmore. I just dont know which parts I need.
CadXS
XS400 Addict
The three different sizes are the distance between the mounting bolt holes. Measure the distance on your tank and order the corresponding part....
Because the vacuum petcock went bad to begin with and I do not see the point of a vacuum petcock. A decent manual petcock will never go bad.
