Fuel pressure regulators and airtex pump.

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lostboy
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Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sat Aug 20, 2016 7:38 am

I did a bunch of reading and wound up installing the airtex pump. It was working absolutely perfect, and then after a hundred miles or so, flooding occurred. I went and bought a spectre fpr rated at 1-4psi and installed it. It's all I could get on short notice. I had to adjust it all the way to get the pressure down enough. Again, it was back to running very well. This morning, immediately upon the pump starting the car started to run like shit and dump fuel out of the tailpipe. I don't have a gauge but I can judge by my glass filter that the regulator is not doing its job. I ordered the holly fpr and a gauge. To my surprise the holly is about 20$ cheaper. Has anyone experienced issues with their regulator? Is my fuel pump growing stronger?? Why would it work without a regulator in the first place if now it needs one? Judging by the Amazon reviews the spectre is garbage. 45$ garbage at my local AutoZone.
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)

Scott V
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Re: Fuel pressure regulators and airtex pump.

Unread post by Scott V » Sat Aug 20, 2016 8:52 am

are you sure you got a real airtex pump? lots for fake pumps out there that look like airtex & have the same airtex number on them.

your pump shouldnt start pumping more pressure.........when it happened that was the time to fix it......not install a fpr. just about any parts place will have the airtex e8016s pump.

if you got a real airtex pump.........they have a limited lifetime warranty. get another pump. cost = 0

-Scott V.

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lostboy
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Re: Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sat Aug 20, 2016 8:58 am

It came in an airtex box. It has only about 200 miles on it. You're sure changing the pump is going to fix the pressure issue?
I got said pump right from amazon: https://www.amazon.com/Airtex-E8016S-El ... B000C1LW0E
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)

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lostboy
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Re: Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sat Aug 20, 2016 9:04 am

You know, I'm going to wait for the gauge anyway. Couldn't hurt to see what its putting out, or what a replacement is.
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)

66vairguy
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Re: Fuel pressure regulators and airtex pump.

Unread post by 66vairguy » Sat Aug 20, 2016 3:46 pm

A bit confusing at first. Airtex sells both a mechanical pump and the electric pump.

Seems you are using the electric pump, and the proper pump model number. They have a good reputation. It should not need a fuel pressure regulator.

Do hook up a fuel pressure gauge other wise you are just guessing. Your problem could be a bad carburetor float, or debris causing the carburetor needle valve not to close.

Also make sure the pump has the Airtex label, a lot of Chinese knockoffs. The Carter pump looks just the same and has not had a good reputation.

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lostboy
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Re: Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sat Aug 20, 2016 5:26 pm

Usually my glass filter stays about half full. Now, even with the regulator, I can see gas rushing in its full, but you can see a strong current in the fuel
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)

66vairguy
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Re: Fuel pressure regulators and airtex pump.

Unread post by 66vairguy » Sat Aug 20, 2016 7:46 pm

I should have said - non Turbo cars DO NOT need a fuel pressure regulator as the carburetors are suppose to work at 4-5PSI.

The turbo cars work best when the fuel pressure is lowered to about 2PSI with a good regulator.

Not sure what you have.

A fuel filter is not a good indicator of fuel pressure. I hope you DO NOT have any rubber hoses in the engine compartment. Corvairs always used all metal fuel lines inside the engine compartment for safety reasons. Glass or plastic fuel filters are another accident waiting to happen. Only use metal canister fuel filters.

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lostboy
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Re: Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sun Aug 21, 2016 5:34 am

66vairguy wrote:I should have said - non Turbo cars DO NOT need a fuel pressure regulator as the carburetors are suppose to work at 4-5PSI.

The turbo cars work best when the fuel pressure is lowered to about 2PSI with a good regulator.

Not sure what you have.

A fuel filter is not a good indicator of fuel pressure. I hope you DO NOT have any rubber hoses in the engine compartment. Corvairs always used all metal fuel lines inside the engine compartment for safety reasons. Glass or plastic fuel filters are another accident waiting to happen. Only use metal canister fuel filters.

Good to know. I indeed do have small rubber connections. I'm going to redo it all probably starting with the pump. This really pisses me off. It's was driving so nicely.
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Re: Fuel pressure regulators and airtex pump.

Unread post by bbodie52 » Sun Aug 21, 2016 6:02 am

:dontknow: Nothing in this discussion seems to point to an inspection of the control system inside each carburetor. Has anything been done to inspect the floats for leakage, or for bent or damaged floats and proper float adjustment, or the condition of the needle and seat assembly in each carburetor? Is the apparent flooding only occurring in one carburetor, or both? The fuel pump isn't necessarily the cause of the problem.

Clark's even offers an improved design for the needle and seat assembly, as shown below...

:link: http://www.corvair.com/user-cgi/catalog ... ow_page=58
Image
Part number C3799: METAL FUEL INLET VALVE-60-69 FITS CARS & TURBOS

Weight: 0 lbs 2 oz
Catalog Pages(s): 48(10),55(12),58
Price:
1 - 3 $ 9.00
4+ $ 8.10

Image

Also, is your electric fuel pump wired to be on whenever the ignition switch is in the ON position, or is it powered through a safety interlock that only applies power to the fuel pump when the engine is being cranked or is running (oil pressure triggered)?

If your pump is on whenever the key is ON, continuous fuel pressure with the engine stopped could inflate the impact of a leaky needle and seat by allowing it to overfill a float bowl when the engine is stopped. The results would of course be immediately apparent when starting an already flooded engine.

Some examples of a fuel pump safety switch are shown below...

:link: https://www.google.com/#q=electric+fuel ... ure+switch

Airtex oil pressure safety switch stops electric fuel pump when engine stops to prevent continued fuel delivery through the system in the event of an accident. An important safety feature when installing universal fuel pump, this switch is designed for use with any universal in-line electric fuel pump.
Image
Image
HOLLEY FUEL PUMP SAFETY PRESSURE SWITCH
The Holley P/N 12-810 fuel pump pressure safety switch is a good peace of mind to help save your engine in the unlikely event of oil pressure loss. The safety switch is installed in conjunction with the oil pressure switch and if a loss of oil pressure should occur, the switch will remove power from the electric fuel pump stalling the engine due to a loss of fuel. This safety switch can help to save your engine if it losses oil pressure. Working Pressure range is 2-100 PSI.


Sample fuel pump safety switch wiring diagram...
Fuel Pump Safety Switch.jpg
Brad Bodie
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lostboy
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Re: Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sun Aug 21, 2016 6:50 am

Yes it's all wired into an oil pressure switch. It doesn't come on until pressure is built by cranking the engine. I had the carbs professionally rebuilt by "Custom Rebuilt Carburetors" in Middlesex NJ. The owner there assures me it's not the carbs but high fuel pressure that's causing the problem. (You know the one thing I don't do myself is probably the issue.) He said even the name brand pumps, because of the ethanol in the fuel have been pushing way larger numbers than what's advertised. I don't see what this has to do with anything. If I disconnect the power to the pump the engine runs fine for a while until of course it runs out of fuel.
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)

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lostboy
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Re: Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sun Aug 21, 2016 6:59 am

Image

I found the box.
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66vairguy
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Re: Fuel pressure regulators and airtex pump.

Unread post by 66vairguy » Sun Aug 21, 2016 8:58 am

The AirTex MECHANICAL fuel pumps have had an issue with high fuel pressure. Many have reported about 9PSI. It's a problem with the spring - nothing to do with ethanol. Many cut a coil from the spring and they work great.

So far I am not aware of a problem with the electric fuel pump. But as the saying goes - "Just because it's new does not mean it's good". It is possible the fuel pump is malfunctioning, but only a fuel pressure gauge will tell you.

As far as your carburetor guy saying "It's the ethanol" - that old excuse is BS. All parts from reputable suppliers tolerate ethanol fuels. I will say I got some off brand fuel hose from a local FLAPS that dissolved. Nothing on the package, but when I went to their site and looked up the fuel hose it said "DO NOT USE WITH ETHANOL FUELS" - that's what happens when you are in a hurry and buy brand X. Later I went to another FLAPS that had GATES "Barricade" fuel hose that is rated for ALL fuels sold today - worked great.

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lostboy
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Re: Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sun Aug 21, 2016 9:24 am

66vairguy wrote:The AirTex MECHANICAL fuel pumps have had an issue with high fuel pressure. Many have reported about 9PSI. It's a problem with the spring - nothing to do with ethanol. Many cut a coil from the spring and they work great.

So far I am not aware of a problem with the electric fuel pump. But as the saying goes - "Just because it's new does not mean it's good". It is possible the fuel pump is malfunctioning, but only a fuel pressure gauge will tell you.

As far as your carburetor guy saying "It's the ethanol" - that old excuse is BS. All parts from reputable suppliers tolerate ethanol fuels. I will say I got some off brand fuel hose from a local FLAPS that dissolved. Nothing on the package, but when I went to their site and looked up the fuel hose it said "DO NOT USE WITH ETHANOL FUELS" - that's what happens when you are in a hurry and buy brand X. Later I went to another FLAPS that had GATES "Barricade" fuel hose that is rated for ALL fuels sold today - worked great.
Wells that's the problem isn't it? I'm in a hurry and just want to drive! Honestly though, I spared no expense, even on the carbs. He's done other carbs for me before. It seems like the left one (bank 2) is the one that spills fuel but I assumed it was because its closer to the pump.
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)

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lostboy
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Re: Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sun Aug 21, 2016 12:58 pm

https://vimeo.com/179672475

Pardon my potty mouth. What's happening here is that I cut fuel pressure and everything is wonderful almost immediately. Once i allow pressure again, well.... You can see what's happening.
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)

66vairguy
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Re: Fuel pressure regulators and airtex pump.

Unread post by 66vairguy » Sun Aug 21, 2016 1:06 pm

lostboy wrote:
Wells that's the problem isn't it? I'm in a hurry and just want to drive!
Not what I meant, but I'll make sure not to comment on any of your posts in the future.

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lostboy
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Fuel pressure regulators and airtex pump.

Unread post by lostboy » Sun Aug 21, 2016 1:08 pm

66vairguy wrote:
lostboy wrote:
Wells that's the problem isn't it? I'm in a hurry and just want to drive!
Not what I meant, but I'll make sure not to comment on any of your posts in the future.
I was kidding 66. Lol I didn't mean any offense. You have been extremely helpful! Problem with typing is that it gets lost in translation. I was actually patiently waiting to see what you thought about my carb after watching the video. Please, don't take any offense from anything I say.
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)

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