anybody run w/o a petcock? /thread size

cf_z · Post by **cf_z** » Wed Apr 15, 2009 10:55 pm

is anyone around here running without the vacuum operated petcock?

mine is malfunctioning, and i am thinking about just running a straight line to the carb.

does anyone happen to know what size threads are coming off the tank (that the petcock attatches to?)

thanks

Kenny_McCormic · Post by **Kenny_McCormic** » Wed Apr 15, 2009 11:08 pm

If you go that way add an inline shutoff, or buy a on/off/reserve style motorcycle petcock.

cf_z · Post by **cf_z** » Wed Apr 15, 2009 11:35 pm

is there really a need for it?

i mean ofcourse if i dump the bike the fuel will spill out, but other than that, theres no real reason right?

CaptDan · Post by **CaptDan** » Thu Apr 16, 2009 12:15 am

cf_z wrote:is there really a need for it?

i mean ofcourse if i dump the bike the fuel will spill out, but other than that, theres no real reason right?

If you ask me (and you didn't) - there IS.

All things being equal, a healthy carb float and valve will keep the fuel from over-filling in the carb. But what if the float goes south? Then what?

Second, what happens when you try to remove the fuel line from the carb for cleaning or maintanence? No petcock? No stoppa da gas.

Petcocks are easily obtainable. Do as HondaSan envisioned, and get a working one for your scoot.

CaptDan>

circusracer · Post by **circusracer** » Thu Apr 16, 2009 10:43 am

I have found a great cure for myself for the malfunctioning petcock. First I went to the hardware store and bought some 3/16" id clear fuel line, a lawnmower type fuel filter with 1/4" barbs, a lawnmower type fuel shutoff with 1/4 " barbs, and one hose clamp. Total cost is around $10.00. The 3/16" line fits over the carb nicely but just a tad loose, that is what the hose clamp is for: the carb. First remove the petcock and take a small drill bit and insert it in the "fuel outlet" of the petcock and drill until the drillbit pokes thru into the main body of the petcock, now you have free flowing fuel with no worries of vacuum. Next reinstall the petcock (no need to worry about thread sizes or fittings) put about a 1 1/2" length of 3/16" clear fuel hose on the petcock, I didnt use a hose clamp here becasue there is no pressure to force a fuel leak and gravity takes the fuel down anyway. Next I took a heat gun to soften up the fuel hose to slide over the 1/4" barb of the fuel shutoff, push on as far as it goes. When the fuel hose cools down it makes a very tight seal, no need for hose clamp. Next step is add a couple more inches of hose to the fuel filter, once again heat gun method, then add hose to the carb.
Now you have free flowing gas on deman, no worries, with a fuel shut off for when you need to remove and clean the carb. I have this set up on all three of my sprees and works great, you never have to crank and crank after sitting for a while to get started.

circusracer · Post by **circusracer** » Thu Apr 16, 2009 10:45 am

I still run the hose from the intake to the petcock, just to make sure I dont run into a lean issue. It has no effect on the flow of petrol.

circusracer · Post by **circusracer** » Thu Apr 16, 2009 11:08 am

circusracer · Post by **circusracer** » Thu Apr 16, 2009 11:11 am

Kenny_McCormic · Post by **Kenny_McCormic** » Thu Apr 16, 2009 4:25 pm

You should cap the vacuum port on the intake mani.

cf_z · Post by **cf_z** » Thu Apr 16, 2009 7:57 pm

i was thinking about drilling it just to see if that was the problem, but i wasnt sure if itd work

thanks man, ima do that this weekend and see what happens !!

circusracer · Post by **circusracer** » Thu Apr 16, 2009 8:19 pm

Kenny_McCormic wrote:You should cap the vacuum port on the intake mani.

Noted, I will take care of that tomorrow and let you know the results. Thanks Kenny

Wheelman-111 · Post by **Wheelman-111** » Fri Apr 17, 2009 3:21 pm

Greetings:

Before you mutilate any innocent petcocks, be aware that these fittings can be purchased in the plumbing department of any Home Depot near you:

Note the item numbers. Assemble with Teflon tape. The barb is too big for fuel line, but a lot of AutoParts fuel filters have a small fuel fitting telescoping into a larger one as sort of shown in pic. Big hose in, small hose out, problem solved. The whole mess was under $20., including filter.

Post by **noiseguy** » Fri Apr 17, 2009 5:13 pm

Wheelman-111 wrote: ...but a lot of AutoParts fuel filters have a small fuel fitting telescoping into a larger one as sort of shown in pic. Big hose in, small hose out, problem solved. The whole mess was under $20., including filter.

I've had problems with that exact filter not flowing enough fuel to the carb. Is that filter working for you?

Kenny_McCormic · Post by **Kenny_McCormic** » Fri Apr 17, 2009 6:04 pm

The problem with running no valve at all is if the float/needle/seat decides to fail, your house/shed/garage or whatever outbuilding have you may rapidly disintegrate into toothpicks.

circusracer · Post by **circusracer** » Fri Apr 17, 2009 9:04 pm

Got a vacuum nipple cap set at autozone for $2.00, capped of the manifold nipple and so far rode three miles today and everything was great.