WTH? Permatex Aviation Sealant no good?

[rodneym]

Background: Holley Black pump to a Holley VoluMax regulator (12-704).
Fuel in, one outlet to the fuel log, the other to pressure sensor (no return).
I turned the key, the pump primes for a couple seconds, fuel pressure shoots to 6 but then kept climbing to 10. Turned off/on, over and over - same 10 psi. If I turned the key on and switched the pump off, the pressure dropped to 0. Tapped on the regulator with a screwdriver handle. No difference. BTW, the high fuel pressure was not unseating the needles in the carbs.
I uninstalled the regulator and opened it up (look at the pics of the fittings). The Permatex Aviation sealant, which worked great, got all crusty inside. It's dry and brittle. I'm thinking that some crust may have gotten in the ball and seat. Or sensor...maybe??? I've taken the regulator completely apart. Diaphragm, ball and seat all look good. I'll figure out the pressure issue (but help would be appreciated) but my main concern is the sealant.
What is best? The white and yellow tapes degrade. Pipe dope looks like hell. Now I don't trust Aviation Sealant.
What are you guys using?



Please help?

[patrickt]

I don't know why it went crusty on you, it's generally regarded as very good stuff. Anyway, a lot of folks, many of whom are much smarter than I, swear by Hylomar Hylomar Universal Blue Sealant - PL32

[Jac Mac]

After close on 50 years I find myself continually re- evaluating sealants etc, what worked good a few years ago doesn't seem to be as good today, because a sealant has aviation approval doesn't mean its necessarily OK in a car environment, their (aviation) fuels etc are under much more strict controls than our mogas etc which has large variations in additives etc, seems to be case of finding what works for you today, but being prepared to change/search out a new alternative when it fails. With fuel lines rather than using sealants its safer to use a banjo or positive stop taper seat fitting or an o-ring/gasket washer fitting, even O-rings have problems with some of todays concotions.

[undy]

I don't think it has anything to do with your sealant or regulator...

The Holley Black pump has no internal regulator like their Red pump does. With a single line system, even with a regulator, you'll see pressure creep. I did and had the same problems when I had a setup like yours. I installed a return line to my tank and used a quality bypass regulator and all my high pressure fuel problems went away.

[bingo2]

I use this: Thread Sealants : Permatex® High Temperature Thread Sealant

[rodneym]

Thanks for the suggestions

Undy, the Holley Red has an internal regulator and the black doesn't?
I couldn't find anything online about this?

Why would pressure creep suddenly happen?

[RICK LAKE]

Rodneym Rod That black material looks like internal partials of rubber hose. I last year went through a problem of fuel pressure and found out that the internal rubber hose has come apart for the ethonal in the gas. I also lost the diapham in the fuel regulator and pressure worked some times or retunred to fuel tank. I don't know how old the lines are in the car but if any rubber is used, you have about 8-10 years. After this time, you can and will get a failure. Gas additives don't help. Not 100% sure on Avigas or race fuel. This is why 5-10 micro fuel filter are so important for a good system. They saved me from cleaning 8 injectors. Did replace all the rubber hoses with stainless, except between fuel pumps and outlets to lines. Good luck ps yellow tape is for oil and fuel lines. Water is for white tape. sealers are for life, one time on. Rick L.

[undy]

Originally Posted by rodneym

Thanks for the suggestions

Undy, the Holley Red has an internal regulator and the black doesn't?
I couldn't find anything online about this?

Why would pressure creep suddenly happen?

You'll notice the note in description "no regulator required" which means it has an internal regulator. That regulator acts like a separate return line, as it returns fuel directly back to the suction side of the pump which is integral in the pump's housing.

Holley Performance Products 97 GPH “RED” Electric Fuel Pump*12-801-1

Here you'll see that the pump puts out 14 PSI and it states "regulator required"

Holley Performance Products 140 GPH "Black" Electric Fuel Pump*12-815-1

With a single line system on the black pump you won't get the fuel return like you get on the internally regulated red pump. What you do get is the constant hammering on the regulator, which over time allows the fuel pressure to inch up. At idle the fuel flow in minimal which makes the hammering and fuel creep worse. My single pipe system also worked OK for a period of time too, like yours. I then started to notice carb flooding and hot start problems. The slowly increasing pressure started to overpower my Holley float needle valves and dribble fuel out the bowl vents.

If you don't really need all the GPM that the Black pump provides I'd switch to the red pump. That would be cheaper and easier than running a new return line to your tank. I really believe that would fix your problems.

[rodneym]

undy,
The Holley Red, Blue and Black all have a Pressure Relief Valves that, if stuck, can and will cause pressure creep, so the Holley Hotline says.
Won't be fun finding out if that's it. Empty tank and disassemble

[undy]

Relief valves and regulators, two different animals. If the regulator is doing it's job then the relief valve working properly becomes a moot point.

Can you give me the link to where you're reading this?

[rodneym]

undy,
There's no link. I spoke to a guy at Holley customer service.
I didn't ask him about the Red. I always though it just pumps at 7 psi. The Black pumps at 14.
He said that if the PRV is stuck (open or closed, I can't remember), that you can get pressure creep. It can get stuck either from the ethanol in the fuel causing water corrosion, or from what they use to test them (if it sat on the shelf a while - I doubt that's it, I've got over 1k miles on the pump).

[Jerry Clayton]

If your running a carb use a mechanical engine driven pump----------

[rodneym]

Jerry, I respect your opinion very much but isn't a mechanical pump a bit sub-par at 770HP? I know I don't live at that HP but I always thought it was good to have a safety factor built in.
Do you have a scoop on something more high-end than a Carter/Holley/Ebrock?
It wouldn't help my fuel temp by going to mechanical but it would be nice to ditch the electric pump and regulator.

[Frank Messina]

I don't know whether it's corporate politics or stubbornness that prevents Holley from telling buyers about the need for return type regulators. Either way, a deadhead regulator is fine for drag racing where the motor is running for 2 - 3 minutes at a time. For anything else a return type regulator is the key to stable pressure and long happy pump life. I like the log style regulators from Mallory and Moroso for their simplicity and functionality. I went with the Moroso and put the $180 difference to work elsewhere. Works great and my fuel pump seems content also
Frank
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