Cascade Crew

nonsensekid20 · Posted: Wed Mar 14, 2012 8:50 pm Post subject: Carb Pickup

So I figure that my stock TBI fuel pump that isn't currently hooked up, needs to come out. Does anyone have a carb pickup laying around? Andy doesn't have the one he had anymore. And on a side note, would it be worth it to cut out the stock metal tubing leading from the tank to the engine compartment and replace it with rubber fuel line?

aaron_sK · Posted: Wed Mar 14, 2012 8:53 pm Post subject:

WTF did Andy do with the one I gave him to give to you?!? Duh

No rubber line under the car. No bueno.

Alphius · Posted: Thu Mar 15, 2012 8:22 am Post subject:

I know it's not the best idea, but in my brother's Trans Am he has my '84 Z28's carb pickup. It had the little pusher pump, which we removed and tossed in the garbage. We then clamped a rubber fuel-rated line to the feed and extended it to the length of a stock non-pusher carb pickup. It's been running fine with that in place for a few years now, and his TPI pump assembly lives in my Camaro's tank now. Maybe you could do the same with the TBI pickup that you already have.

Never run rubber line under the car. The stock line is plenty big enough for quite a bit of power.

aaron_sK · Posted: Thu Mar 15, 2012 8:30 am Post subject:

Gabe, with the setup in your little bro's car there is no sock?

FWIW, as a guy who tends to go overboard, I would find a junkyard carb car and get the entire fuel line from under the car as well as the pickup. That way you don't have the EFI filter under there and it comes up on the correct side of the car for your mechanical pump.

But what do I know. Razz

Alphius · Posted: Thu Mar 15, 2012 9:14 am Post subject:

We attached the sock to the end of the rubber fuel line with a hose clamp. Razz

He got my entire carb lines/pickup/tank and I took the TPI lines/pickup/tank from the '87 T/A for my car.

nonsensekid20 · Posted: Thu Mar 15, 2012 5:39 pm Post subject:

I didn't think I needed it anymore so he chucked it I think. It seems to be pulling through the TBI pump no problem. It's not hooked up. It's just when I hit the gas at any given time it lags then picks up. Someone said it was because it was starving it when I hit the gas since it was pulling it through the old pump. Someone else said it was fine having it like that because if that was the problem it would be lagging all the time, not just when I hit the gas. Not really sure what's right. Could my carb just be out of adjustment? Another person said Holley's are notorious for the lagging thing and going out of adjustment a lot. My head is kind of spinning. (And not from the gas fumes...this time Laughing

)

aaron_sK · Posted: Thu Mar 15, 2012 7:51 pm Post subject:

Pulling through the pump is dumb, you need to fix that.

Running any performance car without a fuel pressure gauge is dumb, you need to get a gauge on it.

Holley's that have been poorly tuned are notorious for bogging.

nonsensekid20 · Posted: Thu Mar 15, 2012 8:12 pm Post subject:

Trying. lol. I need another pickup. Should've just got the one from Andy before he got rid of it. I'll mess around with the tuning again. I thought I had it good but I'll hook the vacuum gauge to it and see what it's doing.

aaron_sK · Posted: Thu Mar 15, 2012 8:47 pm Post subject:

If you had it good and it went bad after a lot of romping on it, take a look at the lever riding on the pump cam.

nonsensekid20 · Posted: Thu Mar 15, 2012 9:25 pm Post subject:

aaron, I noticed you said something about the pump cam in a previous post. "Make sure the pump cam is properly adjusted. The slightest bit of lag in it will cause a huge bog. It can and will come out of adjustment. Iv;e had it happen." How do I adjust this? I was reading what Gabe said before that you hook up a vacuum gauge to tune it. and sent me to this site.. http://www.angelfire.com/fl4/pontiacdude428/HolleyInfo2.html.. however, that didn't tell me how to tune using the lean/richen screws on the side. I know this might be a stupid question and probably was already answered, but I hook up the vacuum gauge and try to get the highest possible vacuum rating. But what vacuum am I supposed to hook it to? vacuum advance that goes to the dist? I've messed around with the screws before and it didn't seem like it did much by turning them. Am I supposed to bump the gas each time after turning it?

aaron_sK · Posted: Thu Mar 15, 2012 9:37 pm Post subject:

That page is a 404 error.

Hook the vacuum gauge to manifold vacuum.

Use manifold vacuum for the distributor as well.

Don't use ported vacuum for anything except passing emissions.

If you screw the idle mix screws in all the way the car should die. If it affects no change you have a blown PV.

Use the vacuum gauge to tune the idle mix for maximum reading at the same RPM (meaning you'll have to fiddle with the tow screws and the idle speed to balance all of them). Make sure sure the two mix screws are about the same position.

A bog-and-go problem sounds like a pump shot issue. Not coming in fast or too small. Stick an eyeball down the throat while working the throttle. The shooters should pump a significant shot instantly. If it's slow you have a misadjustment or the wrong pump cam.

nonsensekid20 · Posted: Thu Mar 15, 2012 9:44 pm Post subject:

I need to fiddle with the mix screws but I also need to get that damn electric pump out of the tank! I keep telling my dad it needs to come out and he insists it's not the problem... and it's kind of annoying. Does anyone have a carb pickup laying around? Sorry Aaron. haha. I should've grabbed the one you gave Andy. I think I went out to get it one day and he was moving or wasn't home. Or something.. But anyway. I need one. I was trying to tell him there's a reason they make carb pickups and TBI pickups. Mad

aaron_sK · Posted: Thu Mar 15, 2012 9:51 pm Post subject:

Put a pressure gauge on it and prove him wrong.

*Edit: If you want a read take a look at this:

http://www.bob2000.com/carb.htm

nonsensekid20 · Posted: Thu Mar 15, 2012 10:00 pm Post subject:

He's convinced it's something between the mech. fuel pump and the carb. and yes the car dies if you turn the mix screws too far. I'll see about getting a fuel press gauge. I can't wait to get that carb pickup in and have it fix the problem. haha. oh and about the rubber lines under the car, IIRC that's what luke ended up doing. But I could be wrong.

nonsensekid20 · Posted: Fri Mar 16, 2012 9:24 am Post subject:

A bit of a read, but actually good info. Wish I would've found this sooner. http://www.holley.com/data/TechService/Technical/Carburetor%20Tech%20Info.pdf

Aaron check out the section on the power enrichment system. Talks about the myth behind blowing power valves.

chevymad · Posted: Fri Mar 16, 2012 10:35 am Post subject:

The holley on my truck has the powervalve protection built in. People can attest to the cloud of black smoke my truck put out when I ruptured the power valve on the dyno. They claim 100%, nothing is 100%

nonsensekid20 · Posted: Fri Mar 16, 2012 2:10 pm Post subject:

I'm hoping that won't be a problem for me. Carbs aren't exactly cheap.

Aaron you don't have another carb pickup laying around in there? Andy was sure you'd have another one. Very Happy

Alphius · Posted: Fri Mar 16, 2012 3:31 pm Post subject:

If you blow out the power valve it is pretty cheap to replace if I recall. You don't have to replace the whole carb. Wink

aaron_sK · Posted: Fri Mar 16, 2012 4:10 pm Post subject:

It is important to read all documentation from Holley with a large grain of salt.

They have good info but they are beholden to the EPA and the Federal government because they are selling you an on-road device. That's why all their manuals tell you to do silly things like run ported vacuum to the distributor.

Power valve is easy. Right between the jets on the other side of the metering block.

Anything can blow out of any orifice at any time in a carburetor. Razz

If you're worried about a blown PV the test is easy as I outlined earlier.

I have no other carb pickup. I had a few EFI ones but scrapped them.

nonsensekid20 · Posted: Fri Mar 16, 2012 8:16 pm Post subject:

Man I don't know the details about carbs. Still learning. Embarassed

But as for the PV, it's not that because if I lean the mix screws too far (or all the way in) the car dies. When I had the vacuum gauge hooked up it read 15 @ 900 rpm. How much would it be to order one from O'Reilly's? And can I take out the TBI pickup and take out the electric pump? Or is it all built in?