Baptism by fire... Electric fuel pump install.

[ahhhoo]

Hello... New member, new car and steep learning curve.... As I continue my quest to try to learn about my new headache, I hope someday to possibly tune my 65 Monza 110 from rough idle issues, Today, I notice the fuel pump is leaking lots of fuel from the seep hole. Reading up, these manual fuel pumps are pretty much garbage. I would like to just pop another manual fuel pump in, but Clarks will not have their new and improved fuel pump out til summer.

This leads me to look into an electrical fuel pump. I have watched a few videos, but I feel (for this amateur) not enough info for me to fully understand the wiring and install. Can anyone recommend any literature, step by step guide, for us dummies?

thanks -al

[American Mel]

I don't know why everybody seems to believe that the mechanical fuel pumps are garbage?
Mine have lasted almost 60 years!
I would say that makes the Corvair fuel pump quite a work of engineering.
Asian imported fuel pumps have had issues, but that doesn't make ALL mechanical fuel pumps bad!
.
Someone will soon surely give you more instructions than you need, he usually does.

[Phil Dally]

Al Lane has the best electric fuel pump wiring diagram out there...wait for his post.

[azdave]

Asian imported fuel pumps have had issues, but that doesn't make ALL mechanical fuel pumps bad!

If Asian pumps are all you can find then that does in fact make them all bad.

8 of the 8 I tested in the last two years from China began failing in around 8-10 miles of use. The shafts are too long or the retainer bolt locator hole is missing or they leak fuel or the O-ring oil seal is cut improperly or the check valves fall out. They are all made in the same place and then branded and boxed for any retailer who wants to sell them as their own product like Delphi, Carter, GMB, etc.

I prefer the mechanical myself and have been rebuilding old OEM pumps for my own use.

[Lane66Monza]

Herer is my wiring for an external electric fuel pump. I used it on a Greenbrier and my 66 More Door. My 66 Coupe is getting Ted Brown's in-tank fuel pump for carbs.

Key points: Don't cheap out on the pump. Get a good one. Have a good electrical system that covers all possible issues. Don't worry about others think about your electic fuel pump control system. Make it do what you want for safety and reliability. My system will shut of the pump in a significant impact to the car or when engine has lost it actual oil pressure.

Since our engines don't have fuel injection, they will run until the carb bowls are empty. You have to aware to turn off the switch in the interim as at idle, engine could run for a minute or two. But you could get Ted Browns EFI system, which would solve that also and get better starting and operation too.

Here is my schematic for the external pump. It will contain same items to control the in-tank pump. Wiring routing will change slightly. I won't have to modify the main fuel line at the front of the car, like has to be done for the external pump mounted behind the tank and bulkhead. Most external pumps are noisy. I have dampened the pump with rubber mounting, but I still hear the tapping of the pump when idling and at slow speed.

Wiring diagram

External pump located on frame behind tank, right side of car.

In-Tank Pump
https://corvair-efi.com/parts-accessori ... -corvairs/

[ahhhoo]

Let me correct myself.... Replacement mechanical fuel pumps. This current pump was bought at Clarks in 12/2022. Also, if their is not a descent mechanical fuel pump on the market, what are my options? Should I wait for Clarks new model?

[Lane66Monza]

Since late 2022 Clark's has been saying they will have a new mechanical fuel pump. This is in their catalog now regarding their advice on using their current pumps. Both pumps are out of stock. So no help in keeping with a mechanical pump. Last word from Clark's was pump would be available in Fall/Winter 2023. Well, we are now in Spring/Summer 2024.

"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."

If you want to use your car this Spring & Summer, get an electric pump in now and wait for Clark's to finish their on car testing in a year or two. Then you can make a decision whether to go back to a mechanical pump. Myself, the in-tank pump is the easiest to do mechanically. It is the original Chevy Vega pump adapted to the Corvair fuel tank sender. Yes, a bit more expensive, but well worth the ease of installation. The electrics will take time, if you do them right for safety and reliability. I understand noise is gone since pump is submersed in fuel.

Anther piece of info on the Vega pump on the in-tank fuel pump mod. You can change the pump by itself using any pump you find, but beware of low cost chinese junk on this pump also. The original pump was a KEM ($50 - 250 replacemeent) from what I could find, but a $55 Carter is a good USA replacement.

Quote for Carter site: "Carter Fuel replacement Electric Pumps consistently deliver fuel at the precise pressure and flow rate the vehicle demands. At Carter we are proud to say our quality Heavy Duty pumps are made in our Logansport, IN plant right here in the USA."


I hope all this info helps you make up your mind.

[66vairguy]

I don't know why everybody seems to believe that the mechanical fuel pumps are garbage?
Mine have lasted almost 60 years!
I would say that makes the Corvair fuel pump quite a work of engineering.
Asian imported fuel pumps have had issues, but that doesn't make ALL mechanical fuel pumps bad!
.
Someone will soon surely give you more instructions than you need, he usually does.

More dumb advice from Amel. I guess he thinks "everybody" doesn't know what they are talking about.

Fact is the orginal DELCO fuel pumps were never exactly reproduced and this is the source of the problem. Over they years reproductions have had problems that are well documented. According to "everybody", AirTex probably did the best job of making a good reproduction fuel pump, but they had some quality control issues when the pumps production was moved to Mexico. AirTex is now owned by another company and there have been no posts about support for the fuel pump.

Clark's has made an effort to find a manufacturer to make a quality Corvair fuel pump, but it is still a "work in progress".

[gbullman]

Al's information is spot on. I did one variation on that by not including the oil pressure safety switch. I figured if the inertial switch was good enough for some factory installs I was OK with just that. The thing with the oil pressure switch is the wiring needs to run the length of the car whereas the inertial switch can be mounted to the inside of the firewall and simplifies things. I pulled my hot from the blade connector fed by the Heater fuse and then have an inline fuse more appropriate for the fuel pump. I also have a manual switch when I want to just run accessories and as a bit of a theft deterrent.

Attached a photo of the Inertial Switch install on my 66. Not sure why the photo rotated 90 degrees when I attached it, click on it and it rights itself.

[aj_ed]

I too agree with some of you on the mechanical pumps. The original pumps have been great for me. I have built 3 engines in the last 10 years, all using used pumps off my shelf. One off my 65 corsa, one off a 63 102, and one from ? I cleaned the rust off them, and re-staked the valves. All 3 hav'nt failed, and still being used. I even built a radical Weber motor (with regulator). Just my experience.

Ed in Wildomar, Ca.

[dixon5553]

i too have not had any issues/problems with the OE pumps....

[Lane66Monza]

There are pros about the low oil pressure switch addition and also the use of a tach signal (no cons to either being used) to control the fuel pump On signal.

I see the tach signal as a nice to have signal, but not much benefit. What causes a loss of a tach signal: bad key switch, loose wire, bad distributor coil or points, either case the engine shuts down and pump shuts down due to loss of tach signal
But if LOP switch was part of the system, pump would have shut down also due to low oil pressure. It more rare to lose a tach signal than oil pressure, in my opinion.

But without the low oil pressure switch in the circuit, if you miss the light on a bright day, one cooked engine. With the switch, pump stops and engine will stop in about 10 seconds at speed due to bowls emptying. Engine will be hurt but not destroyed. You will get the hint of an engine problem when you see speed dropping. Without the LOP switch and you are blissfully cruisin', one ruined engine. Lack of oil pressure cause is either internal or a bad switch. Vega PS64 LOP switch was used in 1.76 million Vegas. I would say very reliable. You can still get a GM labeled today for $20, but Standard price is less than $12, The S956 connector needed for the switch will set you back about $31 at Rock Auto if in stock, otherwise they can range up to $65. Search carefully, if you go this route.

[Phil Dally]

American Mel is right...some original pumps are still in service.

[ahhhoo]

thanks everyone for their insight, especially Al with his diagram. I am going to call Clarks tomorrow to see if they have an update. If the pumps are on schedule, that may play into my decision. :)

[American Mel]

More dumb advice from Amel. I guess he thinks "everybody" doesn't know what they are talking about.

Dumb?
Who is the one who doesn't know the difference between a Statement, and Advice?
I never gave any advice, just an simple statement about my personal observations.
Judging by the follow-up comments, I'd say my observations were/are correct.

[Frank DuVal]

American Mel is right...some original pumps are still in service.

Yes, but they are hard to source for replacements for most people! The local FLAPS does not have them on the shelf.