Pressure regulator?

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Gr8polarbear

Gr8polarbear

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Does anyone know what this is. I thought it was a pressure regulator but can't find anyway to adjust it. The guy i bought the car from said he adjusted the pressure higher due to the dual quads but I think it is to high and want to adjust it back. If it is a regulator how do I adjust it? If not what is it?

20240620_091017.jpg
 
That’s not a regulator. It’s just a simple fuel log.
 
Correct, fuel pressure regulator is somewhere else, between the fuel pump and that log.
 
Does this thing serve a purpose other than show me the pressure and split the line into 2?
 
Gr8polarbear said:
Does this thing serve a purpose other than show me the pressure and split the line into 2?
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That's about it. Are you gonna show us the rest of the fuel system so we can tell you where the regulator is?
 
I might crawl under the car today and see if i can find it. It might be back by the pump because it is not in the engine compartment. I just have the line that comes up to this and goes to the carbs.
 
Gr8polarbear said:
I might crawl under the car today and see if i can find it. It might be back by the pump because it is not in the engine compartment. I just have the line that comes up to this and goes to the carbs.
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Maybe he was pullin your chain?
 
This is what a fuel pressure regulator should look like, may be a different color.

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That is a log style regulator, Moroso used to make them. The pressure is controlled by washers that are inserted into the tube. Personally, I think they are a POS, a friend had one on his race car and it was constantly contaminating the oil with gas. He is lucky he didn't explode the oil pan with as much gas as he had in the oil. I would change it to a screw/locknut style regulator.
 
Sorry if I was misleading, I have never seen a log regulator before!
 
85glht said:
Is this necessary on a stock mechanical pump?
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It could be an issue. We went through this problem with a buddy's 440. The stock replacement pump was putting out like 6#. Joe went to Car Quest for a new pump and it put out around 10#. Without measuring the pressure, you won't know what it is. (unless you are having a rich running condition which is what we were chasing)
 
The pump in my picture is a Carter M 6270, advertised at 6.9- 9.5 psi. I run a 6-pack, didn't think that after checking the fuel pressure that I had a problem. Decided to go with regulator anyway. Those are the Fragolia push lock AN fittings.
 
Another thing I noticed, in the instructions for the moroso unit it says a return line must be used as it regulates pressure after the carbs. What would be the return on the OPs log appears to be capped off.
 
TT5.9mag said:
Another thing I noticed, in the instructions for the moroso unit it says a return line must be used as it regulates pressure after the carbs. What would be the return on the OPs log appears to be capped off.
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Maybe. I thought that capped off end was just another hook up for fuel lines.

Of course I didn’t know Moroso made an adjustable log style return regulator either so there is that.
 
I would sure replace that with a normal holley-style regulator. They aren't real expensive.. I've got two or three brand new laying around, they usually come with the pumps I buy.
I've got the regulator on the inner fender panel, with two braided lines to the carb (holley). The lines and fittings cost about four times what the regulator would cost.
(I just spent $140+ for three foot-and-a-half Teflon lines and fittings to fix a fuel leak on my car.)
 
toolmanmike said:
It could be an issue. We went through this problem with a buddy's 440. The stock replacement pump was putting out like 6#. Joe went to Car Quest for a new pump and it put out around 10#. Without measuring the pressure, you won't know what it is. (unless you are having a rich running condition which is what we were chasing)
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That is exactly the condition that i am trying to fix. The gauge is sitting at 7 psi with the fuel pump on and that is way to much for a carter carb.
 
Nope, 7 psi is NOT to much for a Carter carb [ or an Edel carb ]. I have run 10 psi at the strip as quick way of increasing the fuel level slightly.
Carter published a chart for adjusting float level, relative to needle/seat size & fuel pressure. Chart goes to 10 psi.

img244.jpg
 
That is interesting most things that i have read states that edelbrock/carter starts having issues above 5.5-6.0 psi.

Is there a way to visually tell if the bowls are over flowing into the carb.

I have noticed in the past after shutting car off and not turning the pump off quite a few seconds before i park, the next time i open the hood i will see what looks like brownish spots on top of the intake right below where the primary butterflies are to the left and right side of the carb. I notice this under both carbs. I guess this could also be due to originally it had aluminum spacers and the carbs would get really hot. Now i have phenolic spacers that i just put on and have not drove it enough to see if the spots reappear.

I found out that this unit is a Barry Grant 170020 fuel log.
 
If the carb flooded due to debris under the n/seat [ or excessively high ] fuel pressure, fuel will drip from the booster nozzles.

If fuel level rises because the pressure is higher, but not high enough to overcome the n/seats, then you will not see that unless the float level was misadjusted initially & the fuel level was already high in the bowl. Hope that makes sense!

All of the Carter 4 bl carbs have a very high leverage ratio of the float against the n/seat & are therefore less susceptible/prone to flooding than other brands...
 
Since the carbs are so old what are the chances of the springs for the needle and seat being worn out?

There is nothing dripping out of the squirters.
 
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Gr8polarbear said:
Since the carbs are so old what are the chances of the springs for the needle and seat being worn out?

There is nothing dripping out of the squirters.
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If the carbs are tired it certainly would not hurt to rebuild them. Not an expensive proposition.
 
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