ELECTRIC FUEL PUMP CONVERSION IDEAS & SUGGESTIONS

[bbodie52]

Here are some ideas for reconfiguring the fuel distribution lines in the Corvair engine compartment. We often see somewhat hazardous layouts using rubber fuel lines to connect an electric fuel pump conversion to the engine compartment. The need to route the fuel distribution across the engine to reach several carburetors may create an unsafe conflict with the moving fan belt and pulleys. The comments and photographs below depict two possibilities that help to avoid plumbing routes that can be dangerous if a potential conflict with the fan belt is not considered. The use of steel tubing similar to the original layout is often recommended to help prevent possible fuel leaks that could be a fire hazard.



http://corvaircenter.com/phorum/read.php?1,1045363

Posted by: oldqmguy
Date: September 20, 2019 02:37PM

The Input Line to the Fuel Pump is 5/16" and is a Flare Fitting at the Pump.

The Output Lines to the Carbs are 1/4" and Flared on both ends.

Clark's sells new fuel line kits if you are using the standard factory pump.

This is what I have on my '67 Monza. I am putting in an electric pump so I had to "invert" the lines to the carbs and make a 'new' Input line.

I hope this helps!

Dale cool smiley

Dale E. Smiley CPBE
Life Member The Society of Broadcast Engineers
RETIRED Broadcast Engineer
CERTIFIED CORVAIR NUT
CORSA/Circle City Corvairs/Corvair Performance Group
Avon, Indiana
WB9SFF
1967 4-Door Monza PG!

Fuel Line Layout Suggestion for Electric Fuel Pumps

Fuel Block and Filter Arrangement Suggestion

The Airtex E8251 I selected delivers the correct fuel pressure and fuel volume for the Corvair engine. It is also a fuel pump designed to support marine installations in boats, and because of this the pump also does a good job of pulling fuel long distances. It can be installed near the engine compartment on the Corvair, and does not need to be close to the fuel tank. UNFORTUNATELY IT APPEARS TO HAVE BEEN DISCONTINUED AND IS GENERALLY NO LONGER AVAILABLE. So most electric pumps will require an installation close to the fuel tank. Check the installation instructions for the electric pump you are considering.


A power cutoff for for the electric fuel pump that cuts power if the engine stops for any reason is also recommended. A simple oil pressure sensing electrical switch is often suggested, but such switches are somewhat bulky and in conflict with the oil pressure instrument panel warning light switch that already occupies the connection point next to the generator or alternator. A new mounting point can be created using the "Adapt-a-Bolt" offered by Clark's Corvair Parts that modifies the oil filter mount. The cost for the safety switch plus the Adapt-a-Bolt runs about $52 - $65.


An alternative fuel pump controller is an electronic system offered by REVOLUTION ELECTRONICS. With a price of about $65, This electronic variation uses a tachometer sensor connected to the ignition coil negative terminal to monitor engine activity. If the engine stops, the electric fuel pump power is immediately cut off. The added features not found with the oil pressure switch option include a built-in power relay, a circuit breaker that takes the place of a power fuse for the fuel pump, and an initial electric fuel pump system 3-second pump priming that initializes the fuel in the fuel lines prior to starting the engine.

Fuel Pump Controller
This universal electric fuel pump controller is designed for cars and trucks being upgraded from a mechanical fuel pump to an electric inline or in-tank fuel pump.

• Pump only runs if there is a tach signal from the ignition (Just connect to the negative side of the ignition if you don’t have a factory tach)
• Primes the pump for three seconds at initial key-on.
• Includes a 7.5 amp circuit breaker.
• Includes an internal relay.
• Includes 15 feet of 16 gauge wire to energize the fuel pump.
• One year warranty
• 30 day Money Back guarantee

Where is the electric pump mounted? The original mechanical pump was very good at sucking the fuel from the distant tank though many feet of plumbing to the engine compartment. As long as the plumbing was fully intact, had no air leaks in the two short rubber hoses in the fuel path, and a clean tank with a clean fuel strainer at the tank outlet, plenty of gas would reach the mechanical pump, where it was pressurized appropriately (4 to 5 psi) and fed to the carburetor(s).



Many electric fuel pump manufacturers recommend installation near the tank. These pumps do a better job of pushing the fuel long distances, and they prefer something close to a gravity feed from the tank to the electric fuel pump inlet (filtered). The correct pump must be selected, so that it provides the Rochester HV or Carter YH carburetor(s) with low pressure of 4-5 psi (the Carter YH on the turbo prefers even lower pressure). If you install this type of fuel pump at a high, distant location, such as inside the engine compartment, it may suffer from fuel starvation and might not provide enough fuel volume to the carburetors.

The electric fuel pump I selected for my Corvair was a marine type (Airtex E8251 Universal Solid State Electric Fuel Pump for Marine Applications). It is recommend for installation close to the engine, does an excellent job of pulling the fuel all the way from the tank to the engine compartment area, and provides good fuel volume (Operates at 2.5 to 4.5 P.S.I., delivers 30 G.P.H. at free flow). It is also very quiet in operation.

For an electric fuel pump, this Airtex E8251 seems to be the exception in design that works very well for the Corvair layout. It avoids having to be installed under the car, near the gas tank. It is fairly quiet in operation, and it delivers fuel pressure that is very acceptable to Corvair carburetors.


https://www.amazon.com/Airtex-E8251-Uni ... 693&sr=8-3

Make sure your electric fuel pump is installed according to the manufacturer's recommendations, in a good location, has appropriate fuel pressure for the Corvair, etc.

All electric fuel pumps should have their inlet filtered (by a fuel filter in a metal housing, for safety) to protect the pump. The power should be on only when the engine is being cranked or the engine is running. A safety power switch that senses engine oil pressure or uses a tachometer sensor at the ignition system will insure fuel cutoff if the engine is not running.

I recommend the electronic fuel pump controller. Its cost is a little higher than the oil pressure switch, but because the location for mounting the switch on the engine is already occupied by the instrument panel warning light switch, and this area is crowded next to the generator/alternator, the Adapt-a-Bolt may be needed to place the safety switch at the oil filter location. The cost of these two items is close to the electronic controller cost, and the electronic controller also offers additional features not included with the simple oil pressure switch.


Revolution Electronics Electric Fuel Pump Controller
https://www.revolutionelectronics.com/P ... _Pump.html https://www.amazon.com/Revolution-Elect ... 023&sr=8-3


OTHER OPTIONS...

Holley 12-810 Fuel Pump Safety Pressure Switch
https://www.amazon.com/Holley-12-810-El ... 335&sr=8-3




Mr. Gasket 7872 Fuel Pump Safety Switch
https://www.amazon.com/Mr-Gasket-7872-S ... 335&sr=8-9




https://ssl.corvair.com/user-cgi/catalo ... ow_page=28

Part number C7521: ADAPT-A-BOLT-STOCK FILTER* IF USING W/ OIL TEMP SENDER-NEED TO DRILL ADAPTOR DEEPER

Weight: 0 lbs 6 oz
Catalog Page(s): 28,27D(RM19)
Price: $ 26.40

[bbodie52]

...The availability of replacement mechanical Corvair fuel pumps — now or in the future — is highly questionable. And the price for replacement Corvair mechanical pumps seems to be climbing to far more than a brand-new electric fuel pump! The cost of redesigning and modernizing your Corvair fuel pump system to include an appropriate electric fuel pump with the correct output pressure and fuel delivery volume, proper safety cutoff components, safe, well-designed, and carefully routed fuel lines, a new metal-cannister fuel filter to protect the new electric pump mechanism, and the recommended electronic fuel pump control system, is not that much-more than the $100 (currently unavailable) mechanical fuel pump listed by Clark's...

...
https://ssl.corvair.com/user-cgi/catalo ... ow_page=65

...We have only been able to locate 2 manufacturers of original style Corvair fuel pumps. Since 1973, we have consistently seen 1-2% of new fuel pumps fail. From about 1998-2001, the failure rate went to nearly 10%! We finally convinced the pump manufacturer that they were using the wrong diaphragm material! Currently, about 1%-2% of the fuel pumps continue to have problems. The problems have usually been seepage of fuel or complete failure resulting in no fuel or a rupture of the main diaphragm. The main supplier (C3403) is now using "antiwicking" diaphragms & has returned to all 3 diaphragms having fabric reinforced material. We've also added a pump from a 2nd supplier (C3403A). Our experience with both is nearly identical. A spare pump is always a good idea

Part number C3403: NON-GM FUEL PUMP-62-69 FITS 60-61 IF C259 ROD USED. ** LIMIT 1/ORDER

Notice: This part C3403 is currently out of stock. You may still order, you will not be charged and you will be notified when we have this part.

Weight: 2 lbs 4 oz
Catalog Page(s): 65
Price:
1 - 1 $66.60
2+ $64.60

Part number C3403A: 62-69 FUEL PUMP REBUILD KITS ARE NOT AVAILABLE

Notice: This part C3403A is currently out of stock. You may still order, you will not be charged and you will be notified when we have this part.

Weight: 2 lbs 4 oz
Catalog Page(s): 65
Price: $99.75

Since these pumps are now in short supply (Clark's is currently out of stock from both of their supply sources, and it is unknown when they will be renewed with more pumps), your best bet may be to make the change to an electric fuel pump coupled with a good inline filter to protect the pump and engine (place the filter between the tank and the pump) and an electronic pump controller. see the following...



I noted that the second Clark's pump is now $100 each, and out of stock. The cost of the electric pump I recommended, plus the electronic controller, is about $105. Switch over would also add the cost of a metal-canister fuel filter, and some plumbing hardware change costs. But the Corvair mechanical pump cost is rising and is also unavailable, even from Clark's! It looks to me like the time is now for a switch to an electric pump!

Clark's may have some idea about the future availability of quality Corvair mechanical fuel pumps. If no manufacturer is willing to produce them due to low demand, high production costs, low profit, etc., the future days of new, affordable replacement Corvair mechanical fuel pumps may be numbered. This could be a real problem when a failure occurs on the road, since replacement parts may be made of "unobtanium". This situation may determine the future path for those who drive their Corvairs regularly. A conversion to an electric pump may be inevitable for most owners. I resisted this change and encouraged the continued use of the "proven" and "durable' mechanical pumps for a long time. But if suppliers like Clark's Corvair Parts are having trouble keeping them in inventory, the mechanical fuel pump for the Corvair may become the "Achilles' heel" of the Corvair — especially in those Corvairs that are used often, or as "daily drivers".

An Achilles' heel... is a weakness in spite of overall strength, which can lead to downfall...

Mechanical Fuel Pumps
http://corvaircenter.com/phorum/read.ph ... 693,page=1

[gbullman]

Brad,

Very nice layout of fuel lines in these photos. Gives a good sense of what is possible if you're willing to give up the look of the original fuel feel system.

[1949chevy]

Thank you bbodie52 for posting my LINK...Jimmy

[tjim01]

bbodie52 -

I've been researching electric fuel pump installations for the '65 Corvair I just picked up and saw this post. I've had several Corvairs, but this last one came with an electric fuel pump, but no safety switches and is precariously mounted underneath near the tank. I don't like the setup and will change it, therefore the research. I would prefer to mount everything in the engine bay (I have an aversion to this pump being underneath the car and prefer everything be together and accessible to monitor). This brings me to my point...in the attached pic, is the setup pictured in the engine bay yours? If so, can you define this setup a bit more? It looks clean and tidy - although I'm not sure all components are pictured, but am particularly intrigued by the "fuel distribution block"? Is there an advantage here using the block? I kinda like the idea to eliminate all the hard lines in the engine bay and use SS Braided line from the block....thoughts? Is there a part number for this block?

[County98]

Good post, I'll be doing this soonish.

[bbodie52]

This is not my installation, but I like its looks and layout. The filtered PCV plumbing is all wrong. The PCV tube that includes a metered orifice should be connected to the vacuum balance tube. The end of that PCV tube that normally connects to the air cleaner assembly should still connect, via hose, to the custom air filter on the nearest primary carburetor. It does not need to be connected to BOTH individual carburetor air cleaners... one is sufficient. If you have a 140hp engine with two secondaries, the secondary air cleaners are not an option for connection to the PCV tube.

I would suggest the Airtex E8251 marine-style pump, since it delivers the correct pressure for the Corvair and it appears to be designed to pull the fuel long distances when not co-located with the fuel tank. I kind o like mounting it somewhere forward on the "firewall", on the starter motor side of the sheet metal. This is relatively cool area not exposed to engine compartment heat, and can be well-protected from physical damage. A short feed line from the pump outlet to the fuel filter, fuel distribution block, etc. can be routed through a grommet-protected hole. A marine-style Fuel Filter Water Separator might be considered for your Corvair, Being highly hygroscopic, ethanol will enable whatever fuel it's blended with to absorb more water. If your car sits for somewhat lengthy periods. I feel that the water separator fuel filter might be helpful in removing water before it hits your carburetors. And, as mentioned earlier, the use of a fuel distribution block and high-quality fuel lines will help keep your engine compartment safe from a leak and fire possibility.


Fuel distribution blocks, marine fuel filters, etc. are listed on Amazon.com and many other sources, in many styles and with a variety of features. Search on Amazon or Google it.

[tjim01]

Right on....Thanks for the input. FYI - You blue vert is absolutely gorgeous...I salivate every time I see it.

[65Monza140]

From Clark's "What's New?" page:

Clark Repro Fuel Pump
Initial testing is complete and pumps are being produced! Expected in stock Summer 2024.

C6600R

We will receive 3 pre-production samples and will do final testing before full production begins. Larry Claypool has agreed to also test one & give his evaluation. Although we are testing and evaluating these based on 50 years of experience, nothing will be the same as years of real life usage. Our pumps will come with a 2 year guarantee. For use in Corvair cars and FC's.

Update October 2023: We have continued testing the sample fuel pumps and identified a couple improvements that need to be made. We are working with the factory on these improvements. We are comitted to producing the best pump possible and testing as much as possible. This has caused some delays in the pumps being available but we feel it is worth the wait to avoid problems.

[65Monza140]

Is anyone running EFI and if so, what pump are you using, (What pressure does it put out)?

I'm planning on running Brown's EFI in the 140 using only ONE port per head to start with. I'm not real fond of putting electric pumps in gas tanks, so will probably put it behind the steel wall next to the tunnel in some shielding with an inline filter. Not sure yet.

Any input here is very welcome!

[2LZ]

I have the Clark's setup coming, including block-off plate where the mechanical pump lives. Gonna be interesting.
Normally, an electric pump lives close to the tank. Most like to "push" than "suck". Not sure about the Clark's pump. I'll find out.

[Lane66Monza]

Is anyone running EFI and if so, what pump are you using, (What pressure does it put out)?

I'm planning on running Brown's EFI in the 140 using only ONE port per head to start with. I'm not real fond of putting electric pumps in gas tanks, so will probably put it behind the steel wall next to the tunnel in some shielding with an inline filter. Not sure yet.

Any input here is very welcome!

What don't you use Ted Brown's in tank pump system.

[jimbrandberg]

For EFI I used a round pump behind the bulkhead that was correct for 42.5#s at the fuel pressure regulator at the end of the line. I didn't have to adjust the fuel pressure regulator at all.
It was metric straight threads at the inlet and outlet so it took some time to figure out fittings.
I used the stock 5/16 sender with better fuel injection hose and clamps to the pump.
I used steel alloy line and flare fitting after the pump to the engine compartment in the stock location through the tunnel.
I was worried about vibration noise but it was fine with rubber mount.
There's 2 flare to AN adapter bulkhead fittings at the front of the engine compartment.
I used Aeroquip AN-6 throughout the engine compartment through the 2 fuel rails feeding the 6 injectors and such.
I used 3/8 alloy steel line for the return to tank. I used a welding bung in the bottom of the tank on the left side in the same little angled spot where the sender is on the other side. I put an angle inside the tank so it was not pointed directly to the sender pick-up. I wanted the return under the surface to avoid a lot of spray and fumes on the top of the tank.
It's a drive by wire throttle and if a person wanted to put in the throttle rod again the return line might be in the way but I did try to tuck it out of the way.
In hindsight I would probably just use a 5/16 return line.
I might use Ray Sedman's gas tank section next time, it looks lovely.
I can't remember the pump I used offhand but it's a familiar brand name and I got it from Summit.
Jim Brandberg
Isanti, MN
CorvairRepair.com

[vairmech]

Well pretty much of what has been said here I have just done. I do not believe in making an electric pump PULL fuel as it is meant to PUSH fuel. I also do not hard mount the fuel pump. Sorry, but the Airtex is noisy. I elected to go with a different pump and only 1.5-2.5 psi.
Below is my installation in my 62 van.



After using this controller, I will not use any of the oil pressure switches again, the wires get pretty long with the oil pressure switches. With this you only need to run one wire from the negative of the coil to the front, a tach wire. It even has a 3 second prime timer.


Here is the reason I did what I did keeping everything so tight, it had to fit under the air filter cross tube.


As I said, I do not hard mount electric fuel pumps! If you want to hear the thump-thump of the pump go ahead and hard mount it, it get's real tiring fast.



I know this is a fuel pump thread but I made my own PCV system with NO valve needed. It's modeled after late Corvair system.

[2LZ]

Interesting about the noise when hard mounted. Something to keep in mind. Thanks.
Anyone else on mounting ideas and where?

[Lane66Monza]

On my sold Greenbrier, I mounted a Facet clone square body pump on the outrigger rail behind the tank on the left side. I used a 1/4" rubber pad to insulate it from the rail. Also used rubber washers to insulate the steel bolts, washers and lock nuts from the rail also. Most quiet operation of ones I heard to date.

I would never trust a fuel pump installation to the road hazards and service life a ty-wrap will experience. Give the ty-rap 3 years and it may have failed or will.

Below is a photo of the other improvement I did, which was replace the long rubber hose on the tank with a contoured cunifer fuel tube I made to come down from the sender to the back of the tank. Short rubber hoses are then used to connect it to the sender and the main line. Keeps from pulling a tank down when hose springs a leak somewhere on the length exposed to elements.

Here is wiring diagram I used on my 66 More Door and the sold 64 Greenbrier. Diagram doesnt show wire gage to use, but I used 14 gage if 10 amp fuse protecting it and 18 gauge if 1 amp fuse protecting it. I use the oil pressure switch as the ground for the whole circuit. The 3 way switch up front does the priming with the Momentary side of the switch (up selection). If the fuel pump control circuit fails for some reason, I can select the On position (down selection) to put power direct to the pump bypassing the electronic circuit. The indicator light is illuminated whenever power is appied to the wire to the pump, no matter which circuit is doing the power application. Good troubleshooting tool. If light is on, then either pump ground or the pump is bad.