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Discussion Starter #1
Big fuel leak :eek: on the Alfetta traced to the in-line regulator. Didn't take long to find.:p

Luckily this happened right in the driveway. Well, that's were I noticed it anyway.

It was a regulator like this one (branded CR/Pro):
Mr. Gasket #9710.jpg

Not too impressed with the design, Very surprised that it failed in such a dangerous way. (Note: if in doubt, go and replace yours . . .NOW). Didn't think it was that old but in hindsight, should of replaced it when the rubber hoses were done. Do any of them fail-safe, without dumping fuel all over?

How about this Holley 12-804 low pressure regulator, any better/safer?
Holley 12-804.jpg

Here is Centerline's regulator/filter. Very nice but not sure I like carbs that much . . . yet.
fp458.jpg

Please extend your wisdom.
Thank you.
Gerry
 

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I have used the one that you have on 3 different cars during the past 13 years and they have been trouble free. You might just have got unlucky with yours.
 

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The best advantage of the centerline part is the OEM style. For cars from 50 years ago,fuel was a lot worse that todays pumps supply, and the big glass bowl was needed to provide dirt and water separation.

I have also found that the barbs and the fuel lines are not always compatible. Metric lines are different ID than english ones, and the fuel lines do NOT fit well. This leaves you with the only fuel seal being the compression of a weak 1/2 inch clamp. I've had my OEM set-up leak just by having a bit of english fuel line.

Robert
 

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In 30 years I had not a single problem with the stock regulator, the 3rd one pictured. I used them on any car that had a carburetor. As long as they are filled with fuel they seem to last endless. No need to take them apart and don´t touch it at all if you haven´t got a low pressure fuel gauge to correct the setting after playing with it. It is adjusted perfectly by the factory.

Just clean it from the outside, fit the a new filter, spring and gasket every 20 years and you are done. To test the regulation blow compressed air into the intake. It should come out very limited and produce a sound like some cows do.:confused: Mooo...
If it does not mooo, the diaphragma might have a problem. I only found such a problem by used ones that had been stored away dried out for years. If you use a piece of fuel line to shortcut it, some even work after years on the shelf.
 

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Discussion Starter #6 (Edited)
Just call it 'Good enough'?

I went ahead and purchased the Holley (second pictured in first post). It seemed a better choice than the original Mr. Gasket type as the build quality seemed better and replacement diaphragms are available. The reviews/research on the Mr. Gasket type indicated that the build quality of these have been down in recent years with much of these coming from China (aren't they all?).

While looking for the Holley type, which by the way are sold by various resellers from $22 to over $70 (Eldebrock) for the same darn item, I ignored a review where someone complained that the output pressure would reach pump pressure when not flowing. Well, this is exactly how it works. With the electric fuel pump on and engine off, the regulator output will continue to increase to maximum pump pressure (1-2 minutes). How irritating. I don't remember the old regulator behaving in this manner. But as long as the engine is running, the pressure seems OK (regulated) . . . I guess. I notice the output pressure varying between 1.8psi to 2.5 psi during idle and while revving. Is this a reasonable variation?

At this point I'm about ready to pull it off, return it, and buy a new diaphragm, filter, and bowl seal for an old FISPA FRB-11 that's in storage somewhere. But maybe the current set up is 'good enough'?
Yea, hard to tell but there is a question or two in here somewhere. :p
 

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Fuel regulators don´t fluctuate, as they are there to prevent this. Most probably your carburetor will not suffer from it as long as you drive. But if it reaches pump pressure with the engine off it is defective, as it leaks internally. No other explanation.
Simple Weber fuel regulators keep pressure to fractions of PSI, for years.
Your best idea may be to stay with the old stuff and recondition it. It is a setup that can´t be improved because it just works perfect.

I have seen what they charge for a Filter King, now I understand why you try to use Holley or other! I used to buy them for 15 $. OK, maybe a few years ago...
Maybe you just exchange the one you bought new for a working one?
Maybe not all of them leak?
 

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The Holley regulator has trouble regulating if the fuel pressure delivery is not MUCH higher than the required outlet pressure. And reguardless of what they say in the specs, they dont give a consistant fuel delivery in the 2.5 to 3 lbs that Webers like.
 

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Resurrecting this thread.
The disc type regulators that worked well for me are problematic on my 45DCOE152's. To get adequate flow at sustained high rpm and high load I have to crank the pressure to maximum but now I have some flooding and hot start problems. Can someone recommend a regulator which will pass high volume at low pressure and give stable fuel pressure.
Thanks.
 

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Ed, the Filter King is somewhat similar to the original FRB11's. HOWEVER the range of pressure adjustment with a FRB 11 with a NEW viton diaphragm and bowl seal is about one pound, up or down. The Filter king COMES WITH fuel proof components and has a wider adjustment range.
For originality, I restore FRB 11's. For a better FRB11, try the Filter King. I only have experience with these two and DCOE's.
 

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Richard Jemison
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Fuel issues

Ed, I suggest you pull the covers and check the needle&seat size.
With your engine`s level of tune the normal size old design pieces won`t maintain higher pressures OR fuel the bowl adequately at high demand.

The two main jets, the idle jets, are all fueling at open throttle.
(Assuming 145 mains and 50 idle jets that's 3.9mm of hole for fuel to disperse from. Since a larger diameter hole flows a larger percentage of fuel based on ID than a smaller hole then the largest available Needle/seat should be adequate.
The largest available in the later "sprung loaded ball" design is 3.00 MM (Pierce Manifold part #79503-3.00) which should cure both pressure sensitivity and capacity.
 

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I will take a look at the needle valves and see what I have.

I ordered the 85 mm Malpassi filter regulator from RallyNuts in the UK. $101 inc DHL shipping. I have lost confidence in the current one.
 

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Richard,
flow is proportional to the area of the hole and adding the diameters gives the wrong number. A 2.2 mm hole has the same area as two 1.45's plus two 0.5's.
 

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...and a 2.2mm orifice will flow about 16 gals/hour of fuel at 3psi at zero differential. That equates to an engine producing about 195 HP. And that's for one carb. Having two 2.2s would make it a 390 hp engine.

A stock 1.50mm seat will flow about 7.5 gal/hr. With one seat in each carb, that's about 15 gal/hr, good for a 183 hp engine.
 

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That is useful information, Thanks. I am pretty sure that I have 2.00 needle & seats.
 

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Interesting info at least!
I researched this yesterday, found a bunch of formulae and just plugged in some numbers.

Gordon Raymond knows far more than I do on all the subtleties of the different Webers. Such as 23 vs 26 gram floats in either plastic or brass, variations that may effect needle/seat size. Gordon rebuilt my 40 DCOE 32s with 1.75 seats that went on an engine making less horsepower than yours. There is no want for more fuel even when on the track.
 

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I am probably going with a Malpassi (Filter King) Filter King : 30017FK85V08

Anyone have negative experiences with them?

Thanks.
Ed, I have used the Malpassi Filter King on all my cars for the last 35 yrs +.
I have never had a problem with any of them.
Have one now on each of my Ti Super Rep, and BMW 2.0 NK.

Steve
 

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I have had an offline discussion with Gordon and Jim. My conclusion is that the plastic floats produce higher closing force on the needle valve compared to brass floats due to their shapes (Archimedes Principle). We have all experienced flooding problems with 2.00 and larger seats and brass floats.
 

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You got it! Is that guy Archie 'talian guy? Bettcha 'e iz!
Guido...
 
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