How to check pop off pressure

[rkd]

Is there a country boy way to check pop off pressure? I just ordered a carb kit and four springs. This is my 91 650 LX single carb, SBN.

I have a couple of compression gages, a radiator tester, a couple mityvacs, air compressor, transmission pressure gages, brake pressure test set, etc.

Any suggestions? I was trying to avoid buying the tester, since this is the last 2 stroke I plan to have... (but if needed I will probably get one...I am a tool freak, I guess)

Assuming I still have the stock spring, why would pressure get too high, or does the engine aging just lower the available pressure.

I rebuilt the carb last fall, it ran great a couple times, idled better than ever, and ran fine once this year, but would not restart in the water the last time we took it out. With some starting fluid, it fired right up in the yard to flush.

I thought it was pouting because we got a new VX110, but that does not seem to be the real problem.

Thanks.

[wmsky]

Re: How to check pop off pressure

From the SBT FAQ forum: http://www.sbtontheweb.com/forum/showthread.php?t=13965


Sorry. I didn't read the first sentence well enough first time through. What sadchapter says below should work. From what I can see, a popoff pressure gauge is just a hand pump with fairly sensitive pressure gauge on it that you use to pressurize the fuel inlet of the carb. I'm sure that it also holds the high reading for you as well. But if you already have a sensitive enough gauge, you really just need some way to slowly and carefully pressurize the fuel inlet while you watch the gauge. Hell, you could probably use a bicycle hand pump.

[sadchapter]

Re: How to check pop off pressure

This one might work , use a reduction valve on a oilfree air compressor and set it at 30 PSI , attach a rubber hose or something to the air connector and press it against the hole that fuel goes into and thru needle and seat in carb body . Then increase PSI till it pops , read reduction valves value. Thats your popoff preassure.

There can be no leaks in hose or around hole in carb or you get wrong reading.

When all is tight , perform test 3-5 times to get a accurate reading.