Holley 750dp rebuild

[mrjack10]

I'm rebuilding a 750 DP, 4779-2, and it has not been used for a long time.
Isn't it supposed to be a "loose ball" inside the metering block, that you can hear if you are shaking it ?
Is it just in one meterin block or in both ?

[kudakidd]

the loose ball is in the accelerator pump well. It's a check valve so to speak.

[mrjack10]

So I assume it's supposed to be in both metering blocks for the DP then...
hmmm...they seems to be stucked, because I can not hear them....

[kudakidd]

I hope you're not talking about the brass floats making a 'tinking' sound. The check balls are not that loose. In other words, they won't sound like a bearing in a spray can!

[mrjack10]

Not in acc pump well or in the fuel bowls, I mean inside the metering block...

[kudakidd]

I've been rebuilding Holleys for 30 years and I don't ever recall something loose in the metering block. You have idle mixture screws, main jets, power valve, maybe jet extensions and vent whistles, but the rest is just orifices.

[mrjack10]

Now you're making me confused....
A friend of mine told me that once and as I recall it there was some ticking sound inside the block when I rebuild my 4160 750 couple of years ago...
But when  you have work with Holleys for 30 years I trust you way more than I trust myself and my bad memory...

[MEK-Dangerfield]

There is nothing floating around inside, if that's what you are thinking. Yes, I guess the floats could make some noise if you shake the carb., but that's about it. There would be no purpose for some loose ball floating around in there. In fact, I would be afraid of it plugging up one of the jets. 

  Mike

[Chryco Psycho]

definatly nothing is supposed to be loose inside the metering block

[Oldschool]

Sounds like something may be broken inside there.   Not sure it would be worth trying to rebuild it.....   

[mrbill426]

Those metering blocks are simply drilled castings, no moving (check-balls, etc) inside them.  Mixture screws and power valves are about the only moveable parts there.   Only check-ball I recall in a DP is the check valves in the accelerator pump wells on the float bowls.  What I LOVE about Holleys, very few moving parts to wear out or have to adjust. 

 

[mrjack10]

Thank you all for the info....I must have remembered wrong....The Holley is now rebuild and all jets etc are changed to stock (except for the power valve, had to change that one due to little vacuum with that camshaft). It is my friends Holley, so we put it back to his 70 Duster and my what that car run good.
It has a 360, Kb pistons, ported J-heads, M1 intake, Mopar 292 camshaft and headers.
Only thing that's bad now is the rear ratio...he has 2.73, so I told him to search for a 3.55 that would do good
to that car and engine.