bench test

[screamin deal]

OK just got done putting carb back together after polishing seats and replacing needles. Checked float levels. I am now ready to bench test. I need a slow motion explanation of what and how.

[prometheus578]

With the float bowls off,turn the carbs upside down.. in some sort of tray or baking pan.
Hook up a fuel source.. if you use your gas tank, make sure it's on prime so the fuel free flows.
Ok.. fuel hooked up.. now lift the floats so that the needles rise and gas flows everywhere. (This is done to clear the air from the lines)
Now.. using compressed air, or paper towels, dry everything up nicely.
Sit back and watch for gas leaking at the needle/seat area.
No leaks?
Go upstairs and make a sandwich.
Bring it back down to the garage and eat it while still watching for leaks.
No leaks?
You're done!

[screamin deal]

Thanks for the reply . I will try this tomorrow and hope I do it right. Fuel source hook up may be tricky. I believe it needs to be hooked to the tee's in between my outside and inside carbs. And it will flow up with the carbs upside down with enough fuel pressure. I will let you know how it turns out.
Thanks

[DGXSER]

If you have your source tank above the level that you want the fuel to go to, it will flow there if it can, any liquid will seak its own level including fuel, even syrup will do it, just takes alot longer due to thickness of it.

If you guestimate (or measure) the height of your top of tank on the bike, above where the floats sit when on the bike, and put your fuel source level above that, you will have it covered. This will create at least the same amount of pressure trying to lift the valve off of its seat, as you will have on it when mounted on the bike.

[screamin deal]

Ok tried to do bench test and found my fuel tank petcocks to be pouring fuel in any of the three positions. Test became a mess and was unsuccessful. I now need to fix petcocks. I need to know if they can easily be replaced or fixed.EASILY Ha Ha Ha He said easily. Alright so nothing comes easy for me. Please share your knowledge. Thanks

[screamin deal]

Another question, could this have been part or all of my fuel flow problem in the first place.

[TopCatGr58]

Hey Screamin,

Petcock rebuild kits are easily available from GeorgeFix on Ebay as well as other places, but you need to be sure to order the right kind, there are differences between standard and special petcocks. I didn't check the info in your profile, would be helpful to edit your signature to put the year/model of your bike in that, so that it's quickly seen when folks want to provide feedback which can be very model specific!!

Aftermarket replacements of the entire petcocks are a bit more of a pain, usually requiring an adapter plate of some sort.

The leaking petcocks just helped you to spot the leaking carb problems earlier, but were not necessarily cause and effect!

T.C.

[prometheus578]

I agree with T.C.'s last statement.
A constant flowin' fuel system (bad petcock) will eventually overcome the seal of the needle and seat when the bike is not runnin'. Might take days... might take weeks.

[oldyam80sg]

I got 2 petcocks off my 80 SG if they will fit -you can have them.I put Pingel petcocks on in the late 80's early 90's.You will need the towers but everything is there.

[screamin deal]

OK I am working on my 1979 xs1100sf . How can I put more info and pics in my profile? Annnd will the petcocks off of a 1980 fit cause I sure would rather not rebuild ...with my luck and all. ok onward to search for georgefix.
Thanks, you guys are the greatest!

[screamin deal]

can't find georgefix, only saw petcocks for 650 xs on ebay I think I edited my profile and signature . we'll see

[oldyam80sg]

Does anyone know if these will fit?If they do screamin deal they are yours.

[bikerphil]

signature

Yep, they'll fit. All Special petcocks are the same (left & right).

[oldyam80sg]

O.K. Now that bikerphil has confirmed that they will fit(thanks bikerphil)all i need is an address and they will go out tomorrow.PM me with an address.

[TopCatGr58]

Hey Pete and Screamin',

Slow down, because IF Pete took his off in the late 80's or early 90's, they still have 15+ y/o rubber parts, that have probably hardened anyways, and would still require a rebuild kit! So....look for rebuild kits for the SF petcocks on Ebay, or other sources, like PNM( www.partsnmore.com ), because you'll probably need them anyways, whether with your OEM petcocks, or the ones that Pete could send!

T.C.