Question about Power Valve

[shadowfax101]

I have been running really rich since I bought my jeep. I was finally getting aound the changing the power vavle.(I was told this would help the rich problem). I have a new one and I go to remove the old carb and I notice the power valve inlet on my carb is covered. It has like a cap on it. I was under the impression that is was vacuum opperated..

If it is vac controlled, what should be the source of the vac line? Would a plugged line cause me to run really rich?

Thanks guys

[joe]

Yes, they are vac controlled but I don't know when it changed. Some of the 2150's have a vac line externally hooked to the power valve and some draw the vac from inside the carb w/no external vac source. I don't remember which is which early-late though. My guess is that if there's a vac nipple on the housing for the PV and it's plugged, it(PV) was leaking and someone plugged the vac line.

[shadowfax101]

So when I replace the PV, should I find a vac line to reattach, or should I replug it?

Would having a bad power valve pluged cause me to run rich?

[joe]

Yeah, a torn/leaking PV will cause rough idle(rich) and poor acceleration. It basically works sorta as a vacuum operated accelerator pump. When you accelerate mainfold vac drops and allows the PV to add a bit of fuel. So yeah if you have a vac nipple at the PV I'd hook it up to a manifold vac source after you change the PV.

[mechanic58]

If I were you, I'd take that carb off and set it on a stump and strike it with an ax. LMFAO! That's what I did with mine. I thought I knew lots about carbureators until that GD smog 2150 that was on my 89' wag kicked my butt. If you don't wanna take your intake off...i'd recommend you get a new holley center hung float style 2 barrel and put on it. You'll be much happier.

[TexasJ10]

Before changing the PV, why not go ahead and hook it up to the manifold vacuum nipple that is closest to it on the front of the intake manifold near the thermostat housing? I think it is the same one that has the power brake booster hose on it. Who knows, maybe someone yanked it off without knowing what it was. Someone on here indicated that you could tell if the valve was bad by pulling the cap or hose and seeing if any fuel came out. IF you don't have any, it might still work.

[VAJeepGeek]

I know what your going through... I'm having troubles too, my PV is blocked off too and causing performance problems.
I found this site on the board a while back 'Motocraft 2150 (http://home.earthlink.net/~bubbaf250/2150carb/carb01.html)'. Hopefully it will help, it does really go into detail.

mechanic58 - don't suppose you know which holley works? Model Number that is...? smile.gif

[mechanic58]

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=3821&prmenbr=361 here's a link to the carb you need. This particular one has a manual choke...but I know holley makes one with an electric choke too.

[mechanic58]

woops...almost forgot, this holley will BOLT ON to your existing 2 barrel manifold Fred. BTW, I used to be stationed in NORFOLK. Don't miss it. LOL.

[reddog]

The 2150 is a good carb although it has been known to blow a power valve or two. Having the vacuum to the power valve plugged would cause the power valve to enrich the mixture continually. You can try re-attaching the vacuum line to the power valve but if you have the rebuild kit I suggest rebuilding the carb and attaching the vacuum line to the power valve.

Kerry

[Jeep Craze]

Hey if you are interested in switching to the holley 4412, I have one near perfect only has about 5,000-7,000 miles on it. It has the electric choke (I installed it) and everything. Had it on mine for alittle and decided to go w/ TBI. Let me know(Email me) if you are interested. Craig

[VAJeepGeek]

mechanic58, I don't blame you for not missing this area, it stinks!!! smile.gif

I just posted a diagram under 'Vacuum Dilemma', its pretty much the same topic... anybody with info would be much apreciated.

[shadowfax101]

Ok, thanks guys...I will stick a vacuum line back on to it.

Now I just need to find a free one. I know I had some rerouting done before I got it. I think the vacuum advance is using the vac line for the PV. I will have to work it all out

Jeep Craze..I am interested...I sent you a PM..