Does anyone know of a way to block off the power valves? Will Holley power valve blocks work? I'm running a pair of them and even though I rebuilt them, they leak down and dilute the oil.
Anyone? These are the earlier versions with the check ball in the accelerator pump instead of the little red umbrella.
Pluging the power valve is kind of a race only thing milage will suffer the valve is ether ruptured or the gasket is leaking -wrong gasket.
I'm running two of them in tandem. It is on a stock 260 and they are stock .98 260 carbs. It seems to get plenty of fuel since both carbs function together. It idles great, runs pretty good and awesome at WOT but is a bit rich at lower speeds. I have my accelerator linkage one up from the slowest position at the shaft and the closest to the pump on the pump end. Then it started the leaking down not long after I got it running/driving but didn't do it for a couple months of sitting in the garage and getting started every so often. I am thinking I would like to just block off the power valves and see how it runs. Will Holley block offs thread in and work?
You said it's diluting the oil, meaning it leaks internally. The only way the power valve or anything else is going to leak down the throat of the carb is if the float level is too high or the float needle/seat is leaking. That will also cause it to run rich. I'd check the level first. And fuel pressure. Another thing that will get fuel in the oil is a bad diaphragm on the fuel pump. If you have a PCV system it will suck up the fuel vapors and run rich at part throttle.
To answer your question, the threads are the same. I have used the Holley power valves in a 2100 before but I have never tried to block them so I can't say if that will hurt or help your issue.
That makes sense. I am still running the stock fuel pump but it was a new one, don't mean it isn't leaking.
I'm new to the 2100, and was surprised how similar it is in design to a 94. Gonna run one on a 302. I tried plugging powervalves in a dual 94 setup, and had limited success. Tons of jet changes. Was wondering if you rebuilt yours? Is the throttle shaft sloppy? Sometimes that has a leaking effect (other then previously stated) Now I'm going to be on the hunt for a dual 2100 intake for my 302! TP
I am still wondering how the float bowls leak down when it's parked and still have the idea that's what's diluting the oil. I guess I need to take a closer look at the carbs even though I did rebuild them both. BTW, I built my own intake using a 302 EFI lower and setting the carbs on sideways. There's quite a bit more to it than that but basically that's what I did.
If you look at your carb you will see vacuum passage between the power valve chamber to under the throttle plates if there is a hole in the diaphragm or the gasket is bad fuel will leak through or around the power valve through the vacuum passage into the engine. The first thing you will notice it will be hard to start after sitting a few days because the float bowls will be dry.
First off, kudos on a homebuilt setup with some kool factor. Second, please seriously try to work with the power valves instead of against them, you might have a ruptured one or block passage or something else entirely going on- but removing the PV's on a mild street engine is pretty much always a bad move.
Yes you can use a Holley power valve plug on your Autolites. I have a 3x2 Autolite setup on my dad's 348 in his '58 Chevy pickup and the I blocked the power valves on the outer carbs with great results. The Autolite is by far the best running carb ever made, just keep tweaking on it.
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