All Small Six Help! Did I just screw up my new build?

[Frank]

Mechanical fuel pumps don't release pressure. When a hot engine is cut off they frequently build pressure, can be double-digits, because of the fuel heating up in the lines near the hot engine and nowhere to go. Can't know if there's a pressure issue without a gauge.

 

[awasson]

Hey! Great news @WillingnessLimp!!! That is fantastic. I was hoping it was something non-destructive.

Now, regarding the spacer... You have uncovered my suspicion about a vacuum leak. That spacer does not have gaskets glued to it. That is a piece of phenolic and it has paper bonded to each side to protect the surface while it is being machined. Plexi and Lexan has the same material. You need to add gaskets to each side. You can leave that paper on or remove it. If it's saturated with fuel and has been leaking, I'd remove it and put proper gaskets on each side.

I am so happy you've discovered the issue and it was simple.

Cheers,
Andrew

 

[WillingnessLimp]

Mechanical fuel pumps don't release pressure. When a hot engine is cut off they frequently build pressure, can be double-digits, because of the fuel heating up in the lines near the hot engine and nowhere to go. Can't know if there's a pressure issue without a gauge.

Got it! I’m gonna add 2 fuel pressure gauges: after pump (before pressure regulator) and after pressure regulator (before carb).

Thanks @awasson! Yeah, I was under impression that those papers are acting as a gasket as well…another learning curve lol
I have 2 gaskets, that I’ll use next time, just need longer carb studs then

 

[awasson]

You've got the same fuel pressure regulator I have and it's mounted where mine is too. It has a 1/8" NPT fitting that faces you if you're looking at it and that is meant for a Fuel Pressure Regulator. I bought this one:

https://www.amazon.com/Measureman-Glycerin-Pressure-Stainless-0-15Psi/dp/B07T71VDVB?th=1

It has a rubber stopper at the back. Before you install it, remove the stopper to allow the pressure to normalize and then put it back on.

 

[drag-200stang]

I see no point of the second gauge before the reg. Maybe temp just to see. It is the pressure at the carb that matters, if stays good at all times, that is all that matters. If this was EFI then we may care.

 

[WillingnessLimp]

I see no point of the second gauge before the reg. Maybe temp just to see. It is the pressure at the carb that matters, if stays good at all times, that is all that matters. If this was EFI then we may care.

I guess I was thinking to check the inlet pressure, as Holley states to have a max inlet pressure of 7 psi.

 

[WillingnessLimp]

You've got the same fuel pressure regulator I have and it's mounted where mine is too. It has a 1/8" NPT fitting that faces you if you're looking at it and that is meant for a Fuel Pressure Regulator. I bought this one:

https://www.amazon.com/Measureman-Glycerin-Pressure-Stainless-0-15Psi/dp/B07T71VDVB?th=1

It has a rubber stopper at the back. Before you install it, remove the stopper to allow the pressure to normalize and then put it back on.

Thank you! Didn’t know it has an outlet for a pressure gauge.
Honestly, I don’t remember an outlet on the face of it, but I’ll take a look tonight. You are not talking about second outlet for the fuel, right?

Also, does this outlet on the carb should be plugged or left as it is?

 

[DON]

I see no point of the second gauge before the reg. Maybe temp just to see. It is the pressure at the carb that matters, if stays good at all times, that is all that matters. If this was EFI then we may care.

I kinda like the idea of knowing what the fuel pump is doing. Especially since there are so many problems with them

 

[WillingnessLimp]

Having a thought about the rocker arm.
When I was cleaning/rebuilding it, I got new rocker shaft. And when I was putting it all together, the arms were sliding in nicely, but the support “towers” seems having troubles sliding in and looked like there were turning into slightly oval shape. I had hesitations about putting it all back together, but because arms were moving freely, decided to run it like this.
In this case, should I consider replacing the whole assembly? Or just get all new arms and supports?

 

[drag-200stang]

That is kind of normal. If the stand/tower bolt is over torqued it can damage it, do not over torque them. No more than 35 ft lbs. and two turn for each bolt at a time till tight.
It is probably fine as long as the rockers move freely and the stands show no signs of cracks. You will have to be the Judge as we cannot tell from here.
Also if the shaft has a flat ground the length of shaft it should be down for better oiling.

 

[DON]

That could be wear on the stands, maybe measure up and down then across and see the difference, then a measurement on the shaft.
Even if there is wear on them, I don’t think that is your problem

 

[awasson]

Thank you! Didn’t know it has an outlet for a pressure gauge.
Honestly, I don’t remember an outlet on the face of it, but I’ll take a look tonight. You are not talking about second outlet for the fuel, right?

Also, does this outlet on the carb should be plugged or left as it is?

Darn. I had a closer look at your video and you pressure regulator looks like it's different unless it's backwards to mine in the mounting bracket. Below is a photo of mine with the fitting for the gauge.



The outlet on the carb is an overflow. Mine has never over flowed but to be on the safe site, you could run a line to dump it somewhere away from the engine. Maybe another catch can arrangement.