Check what I just pulled out of my carb. It was purchased from NAPA and installed 6 months ago.
I began to notice some sticking of the throttle on acceleration and this was the cause. I thought the blue cup was good in alcohol.

I bought a new one from Cliff Ruggles. The shaft is a bit shorter, but it works just fine. Lets see how long that lasts.

 

Your the second one to suffer this problem recently. I wonder if the gas station you frequent is keeping the ethanol at no more than 10%? Hopefully it's fixed.

 

Who knows what those gas guys are doing. Soon it will be worse thanks to 15%. I am normally a supporter of Clean Living, but using food to power cars makes no sense.

 

pcard,

Make sure the quadrajet accelerator pump bore is nice and smooth too.

 

Not all blue cups are the same. The amount of ethanol scares me. I had some roughness with my 2007 Charger R/T a couple years ago. The dealer showed me some samples of area gasolines, with ethanol as high as 30%! I'm not sure if that would effect even the best pump cup. It sure made the car run lousy, and the dealer said it was really srewing up some cars fuel injectors.

 

Joe (costpenn) just went through this with his 455 too. The new one he got from Sparky seems to have turned the corner, at least that's what he says.

From what I read on that thread (Bill Demmer) there's no guarantee how long any of these parts last with ethanol fuels, and most of the suppliers get their parts from the same source.

Good luck with the new unit Peter.

 

Joe - I thought of that after I had got that little choke rod hooked in the lever (you know what that is like), so I am taking my chances.

Thanks Allan, I will update if I have to go through this again.

Cheers, Peter

 

Grrrrrrrrrrrr.

I just put a pump plunger just like that one in my QJ about 2 months ago.

I'll keep an eye on it, and I'll report back if it fails.
If so, then it's Cliff or Sparky, and we'll see whether that one is better.

Very frustrating.

- Eric

 

we stopped using the blue cups-nothing but problems, I'm sorry to say. These were especially recommended for use with ethanol fuel. We went back to the black cups with very few problems.


bill

 

I've noticed a couple different blues too. One that came out of my '73 qjet was on the car for about six years (came with a rebuild kit from NAPA) and that was a lighter blue; the cup is still nice and soft too. The pump in the rebuilt kit that i got from Ruggles for my '72 qjet earlier this year has a darker and slightly smaller blue cup but with that spring behind it, it was a tighter fit in the accelerator pump bore.

 

You will certainly be inside of that qjet again, probably sooner than later . It can be addictive. "What do you do in your spare time, sir?" "Uhhh, Rochester Quadrajets". Next time i'm going to do it blindfolded, so I'm thinking about having a representative from the Guiness Book of World Records over.

 

I think the whole rubber parts issue is a moving target. It changes as the fuel changes. I used to buy NAPA kits too. At one time I started also buying an additional separate special pump with a blue cup (impervious to fuel additives) and it worked fine. But then the fuel changed. When did the 5% ethanol change to 10%? When did they add, then eliminate MTBE (Or what ever it was) and what replaced it?

The rubber parts have had to evolve as the fuel has changed. Cliff's cups ARE a darker blue than the blue NAPA sold, and they have the spring that keeps it tight in the bore. Cliff told me they had a run of bad cups a few years back but they were replaced by an updated version. I got one of those cups (on a red plastic pump I think) and it did fail after 3 1/2 years. When it finally failed, it would pump fine, but it stuck down in the bore and the spring couldn't push it back up immediately like it should. Cliff replaced the bad part, but again, it failed after 3 1/2 years and changing fuel configuration.

 

Thanks, Bill. That's good information, there.

- Eric

 

Just when i thought about replacing mine, I will wait....
Crap parts and crap gas - what a combo...