Note: Please post questions in the Rubberside or PM me...

...a faulty vacuum operated petcock can cause either a flooding, or starvation problem, depending on the failure...
...both are very common, and they can both be dangerous...

So,... here's how to check your petcock,...

Check the vacuum line that goes from the rear of the petcock to the right side of the carb (Hint: it's usually covered with a chrome spring).  
If it has any fuel in it at all,... the petcock diaphragm is leaking and needs to be replaced.  You may have to give a light suck on the line to find out for sure (not kidding,... it may only leak when vacuum is applied).... (This will only test for flooding, or rich, sputtering issues)...
If you don't find any fuel in it,... you're not done... you need to go on to the Prime and cap test...

Oldfeller--FSO wrote on 10/03/12 at 12:36:07:

 
To do the Prime and cap test, start by pulling the vacuum line off at the intake port on the carb, and blocking it, and the line that connects to it coming from the petcock ...(Note: just pulling the line will create a HUGE vacuum leak,.. BOTH ENDS MUST BE CAPPED!)...



Then ride, with the petcock set to prime, and see if it runs better... If it runs better, the petcock is bad...

The vacuum petcock can be the cause of both,...
...fuel starvation,(if the vacuum diaphragm does not hold the fuel line open, to let fuel flow)...
...or flooding, (if the diaphragm leaks, and lets fuel run down the vacuum line, directly into the intake)...  
... in the former case,... if you have been experiencing fuel starvation,... particularly at highway speeds... you may be able to cure the problem by replacing the vacuum hose, or tightening the fittings... maybe...
...in the latter case, if the diaphragm is ruptured, fuel will fill the airbox and crankcase,(in which case you must drain the oil and replace it, and clean the airbox and dry out the filter)...

If you find gas in the vacuum line, or if it runs better in the test,...
...you have four options....
-replace with a new stock petcock,... ($80.00)
-rebuild it (Versy has instructions for this, also in the tech section),... $25.00)
-convert stock petcock to manual,... (free, but work)
-or replace with manual, Yamaha Raptor 660 petcock....($25.00)

... a new stock petcock will run you about $80.00...

Versy rebuild instructions are here...
http://suzukisavage.com/cgi-bin/YaBB.pl?num=1268804471/1

bobo383 has a clever conversion to manual on/off/reserve that has worked well for me,...
http://suzukisavage.com/cgi-bin/YaBB.pl?board=tech;action=display;num=1113631600

...but I eventually went with the Raptor petcock because it also makes tank removal easier....
This is the Raptor part no.  5LP-24500-01-00
2003 Yamaha Raptor 660 YFM660R
http://www.ronayers.com/browseparts.cfm?SearchString=5LP-24500-01-00&adv=5&kw...
NOTE... ( all Raptor 660 petcocks fit,... I included a specific model/year for internet ordering, and anal retentive counter salespeople...) (Raptor 350 petcocks won't fit)...
(also note,...the Raptor petcock clears the frame easily, and makes tank removal much less hassle)...
The Raptor is a direct fit replacement,... just remember to cap the vacuum tap on the carb...

Quote:


Here's a view of the Raptor petcock installed...


Quote:

Serowbot wrote on 09/02/09 at 16:00:29:

Actually you have 5 options, add replace vac line and replace diaphragm.  I've had to replace my vac line just about every year.

Any parts store has the little rubber boots that go over the nipple in the carb body and yes you do have to block it off.

Here is your tech post with videos for how to put on a Raptor petcock.

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1315418285


===================


Yes, fuel filters are a good thing.

Here is your tech post for a filter mod.

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1211846392

Does the amount of reserve change with a Raptor petcock? If so by how much?

Reserve on a vac stock petcock is 25-30 miles

Reserve on a Raptor is 20 miles

Nothing bad happens... it is just a safety valve...
It's good practice to turn it off when you park,.... just in the off chance that your float sticks... but, that is a very unlikely occurrence...(in the 1960's and earlier, before o-ring gaskets,... many carbs tended to weep fuel when parked, and shutting off the petcock stopped this)(modern bikes don't weep, unless something is broken)......

It's kinda' like asking,... what happens if you don't wear your seatbelt?...
Do you die?...
No...  only if you are in an accident,.. and that accident is serious,... and it occurs in a way that the seatbelt will save you...

Now,.. I do wear a seatbelt in my car,.. but my bike doesn't even have one, and I definitely wouldn't feel safer if it did...

I ridden bikes for 30 years... 26 of those were on bikes with manual petcocks...  and I only ever turn mine off, to remove the gas tank or do carb work...
I have had a stuck float one time in those years,... but it occurred, while I was riding, so a vacuum petcock would not have prevented it.
... and had I not noticed, a vacuum petcock would have hidden the fact from me until I rode again... That's not safe...
(EDIT ...just remembered, I've had a stuck float twice... second time I was parked, and saw the puddle)... there would have been no puddle with a vacuum petcock, but the float would still have been stuck, and would have continued it's leaking once I started up......
I'd much rather see the puddle of gas under my bike while it's parked, than get on it and find out at 60mph on the freeway...

I've bought, fixed, and sold 6 , and maintained 3 more Savages, plus owning one for 5 years, and seen 4 vacuum petcock failures in that time cause, (not prevent), a fuel leak that flooded the engine and airbox with raw fuel...

A "safety feature" that causes more leaks than it prevents, is not a safety feature...  and you will find no official word from Suzuki that it is a safety feature... it is a convenience feature for those that would forget to turn it on or off...  Many people, even mechanics, think it's a safety feature because they don't understand how it operates...
If your float ever sticks, and you have a manual shut-off... turning that off will stop the leak... a vacuum petcock will do this automatically, (as long as it is working properly), and only once you stop, (not while the engine is running)...
If your vacuum petcock ever leaks... there is nothing to turn it off...  You will have to quickly find some pliers, disconnect the vacuum line, find something to block off the hose, then disconnect the fuel line, and do the same,... all the while gas is flowing, possibly over a hot engine...

A vacuum petcock is an accident waiting to happen...
... about a third of members here have experienced a failure...
... another third probably will in the future...
.. and a last third will get lucky, and not have a problem...


Now, you have to ask yourself a question?...
"Do you feel lucky, punk?...  ...
Sorry,... didn't mean to call you a punk... it's just too cool of a quote.. ...

List of Things That Tell You It May Be Raptor Time


1)  Your bike stumbles or acts like it is running out of gas when you are going over 55 mph and then when you get to the pump you can't put in 2 full gallons of gasoline.

2)  Your bike dies on you and you play bloody hell getting it to start again (you can't get any gas from your sick vac petcock no matter what you do to try to get it to start).

3)  When you get a reserve situation and roll the vac petcock toggle to Reserve, the bike continues to stumble for nearly a minute before slowly picking up some power and speed as you struggle to get to a gas station.

4)  You get all sorts of abrupt indications your carburetor is dirty or your jetting suddenly went off (and you haven't changed your exhaust system or air filter system).   Especially applies if SeaFoam, etc has NO EFFECT on your "carburetor issues" whatsoever when you try it.

5)  You smell gasoline either coming from your vac suction line, your airbox or from your oil fill port when you unscrew it (so you can sniff your oil in the sump for the scent of gasoline) because you suspect you have one of the above going on and "it may be Raptor Time".


(actually matey, if you get to #5 and smell gasoline in your oil it is way past Raptor Time already and you may have damaged your bike some already)

Approximate Time Line for Various Petcock Issues


Always under development based on new information, check the revised date down at the bottom of the post for latest revision date.  
Also note the middle items can switch order position for you (the dates do overlap a lot you know)


1)  Vac line getting cracked/holey is the first item in the time line.
(Note:  this time line assumes you fix the vac hose and keep it fixed by yearly replacement or honestly, you will never get past step #1 to get to the rest of the items)
year 5-10

2)  Diaphragm getting partially stiff and failing to flow enough gas at full speeds is the second item in the time line.  
We generally call this "stumbling at highway speeds".
years 7-15

3)  "False reserve" indications start somewhere about here too.  years 7-15

4)  Getting an occasional (rare) stuck float at the ends of float bowl travel (3 raps with the screwdriver handle fixes it) starts somewhere around here too.  These generally happen when the bike "runs out of gas" on the open road when you still have like a half of a tank of gas.
years 7-15

5)  Diaphragm getting so stiff you can't start the scoot sometimes after it dies on you.  years 15-25

6)  Last comes diaphragm pinhole/crack death and the dribble of gasoline down into the air box and the sump.    years 15-25

Finally I received my Raptor Petcock, Spark plugs, and Oil Filters (Tomorrow I will get my brake pads)  


While waiting fot my parts I stopped  to Autozone, Pepboys, O'Reilly's to buy all this stuff :  Clamps, 2ft, 1/4" Fuel Line, Fuel Filter, and 5/32" Vacuum Cap (3.96mm)



Raptor Petcock Installed with fuel filter :


This is how the vacuum cap fit perfectly :  


  I Can't wait to Ride it tomorrow (/or later) with a new petcock, new oil change, new spark plug I just finished doing all this work today at 12am (4hrs of work and beer breaks ) ... Time to get a rest Zzzz for the big Test ...