Electric Fuel Pump Install

[SneakerZed]

Good Day Everyone,

I have a good friend who lives where he does not have an internet connection and he asked me to help with modding his CUCV M1008 with an inline electrical fuel pump and a spin-on fuel filter. All the parts have been purchased but I have a few questions that (maybe I missed or just could not find) about the install (I am by no measure a mechanic):

- As suggested in a post, I would like to wire the fuel pump (12v) to the ignition but I do not know where to run the wires too. Could someone let me know where to connect the wires too - A pic would be awesome.

- Can I leave the existing fuel pump in place? And if so do I just plug it? If it must be removed, where can I get a cover plate for the hole?

Thank you

 

[cucvrus]

OK I have to ask. Why change it to electric? I got to know why. The OEM pump is a breeze to change. My wife changed several of them just to prove she could do it. I was there giving her tips but she changed it in 1 hour. How easy is that? As a previous owner no fewer then 50 CUCV's I have never did any of these changes and see no reason to do so. That is my opinion. I drove my 1984 CUCV M1009 to Baltimore and back yesterday. And put 150 miles on it today. ALL Stock. Again my opinion. And I have been working with these trucks for 30 years. What do you gain? The OEM pump is $20. at Autozone and has lifetime warranty.

 

[MarcusOReallyus]

Feel free to ignore cucvrus. He goes on this rant every time somebody mentions switching to electric. There are pros and cons to both. Some can't see that, and insist it always has to be their way.

A few random answers for your questions:

1. The cover plate is standard 350 Chevy block. Easy to find on the Internet. You can get a chrome one for just a few bucks, if you want to look tacky.
2. I would not power directly from the fuse block. I would run a fused line from the 12v block on the firewall, and then switch that with a relay triggered from a hot point on the fuse block. You want it running when the key is in the RUN position. That way you aren't putting a load on 30 year old wiring.
3. In a couple of threads, I have read about some folks leaving the mechanical pump in place. I guess that gives you the best of both worlds.

 

[gimpyrobb]

What did the pump and filter cost you?

 

[Recovry4x4]

What did the pump and filter cost you?

Opportunist!

 

[gimpyrobb]

Hey now! He said he already has his pump and filter.

 

[MarcusOReallyus]

Opportunist!

You say that like it's a bad thing?

 

[SneakerZed]

I believe the cost for everything was less than $200

 

[cucvrus]

That makes perfect sense. I always spend $200. when I can fix something for $20. and some labor. NOT. Why not ignore common sense.and go with the masses. Start cutting lines and add things that only you know how it works. That way you have a totally top secret design and your the only only one that knows what is supposed to be there and what is not. It makes future diagnostics a joy for all. A fuel pump that just hangs on the side of an engine and does nothing is still a potential place for an oil leak. Just saying. Ignore me now but ask me later. I liked the OEM plan so I stick with the OEM plan. 500,000 plus miles of CUCV personal use experience. Sorry to offend but it is the truth.

 

[Skinny]

Oh no...not the dreaded electric fuel pump controversy.

I for one like the simple pimple mechanical pump, it has served my use just fine. By searching, you will be able to find plenty of install write-ups of how to get the electric pump in and what to do with the old mechanical pump. I certainly don't want to see this spiral out of control of what to do as I think we have been down this road before. I would do some reading before making a decision on what to do for yourself. Certainly ask any questions after doing some due diligence as we are all here to help based on what you want to accomplish.

Wow, that is like my first politically correct post

 

[acesneights1]

To the OP, good idea. Get rid of the mech pump. It was a bad design and GM later went to electric LP's in the GMT400.
The mech pumps, they are OK but when the pump gets a little worn the electric pump helps prevent drain back also the fuel pressure is more stable with an electric pump BUT you need to use the right one. Any ol electric pump can cause issues. You want 4-7 psi.more than 7 psi messes with the cold advance .Also you want a pump that is flow on fail. The Db2 Can run with no LP but you will see a severe loss of power. Also on the mechanical pumps can leak diesel into the crankcase. Don't leave the old mech pump on the engine. It will eventuallly leak oil. The best LP to use is the factory GM lp for a 93 K3500, 6.5td. It was the best flowing pump and was designed specifically for the DB2. Having an electric pump also makes fuel filter changes much easier. Most people tap power lead to the IP and route power to the LP via relay. It is best to incorporate an OPS from 93 K3500 as well . This will provide fire safety in case of collision.
Feel free to PM me with any questions. I have converted many 6.2s. I run an Airdog on mine but that is way overkill and unnessicary.
I ended up with a spare one thanks to the slimeballs at Lee's Auto Ranch.

 

[Recovry4x4]

Good Day Everyone,


- As suggested in a post, I would like to wire the fuel pump (12v) to the ignition but I do not know where to run the wires too. Could someone let me know where to connect the wires too - A pic would be awesome.

- Can I leave the existing fuel pump in place? And if so do I just plug it? If it must be removed, where can I get a cover plate for the hole?

Thank you

Starting right now, if you have answers or advice directly related to the questions quoted in red, feel free to offer that info. If all you want to do is feed the debate over which is the proper or preferred way to deliver fuel to the injection pump, pick at others or advise others to ignore posts, prepare for a well deserved vacation. The original poster asked specific questions, help the guy out instead of this ridiculous hijack of his thread.

 

[llong66]

Hi, I converted to an electric pump as part of my 6.5l turbo install. I used a fuse tap from the fuse block and wired in a fuse, 10 amp I believe. Im sorry I cant remember which fuse I chose but you want one that is only hot when they key is on, easy to confirm with a volt meter or test light. As already stated, you can use the blockoff from a sb chevy that almost any autoparts place should have. You will want to make sure and keep, I believe it is the bottom two bolts as they are specific to the 6.2/6.5 motors. You dont want to leave the old mech pump on as running it dry WILL cause it to fail and you will have a serious oil leak!
To Acesneights1, can you please elaborate on what you mean by OPS from a 93. I am all for doing anything I can to Increase safety! As I said, I did not go the relay route but may in the future.

 

[acesneights1]

The oil pressure sending unit on the 93 also doubled as a safety switch for the lift pump. It would not turn the lift pump until the oil pressure builds and turns it off in case of loss of oil pressure. If you wire your lift pump to keyed power direct and crash and your truck is burning your lift pump will continue to fuel the fire. I realize this is an unlikely scenario and most people don't worry about it but it is the right way to do it. You would have to tee the 93 OPS into your oil supply and use it soley for that as the sending unit function probably wont work with the CUCV idiot light.
It's best to supply keyed power through a relay that connects the lift pump directly to the battery. I'll try and draw a schematic later

 

[phil2968]

So when you turn your key on the lift pump will not operate because of no oil pressure. That will make it tough to bleed the air out after an oil change. You would need a bypass switch.

 

[MarcusOReallyus]

Hi, I converted to an electric pump as part of my 6.5l turbo install. I used a fuse tap from the fuse block and wired in a fuse, 10 amp I believe. Im sorry I cant remember which fuse I chose but you want one that is only hot when they key is on, easy to confirm with a volt meter or test light.

I don't recommend this approach. Run power from a solid power source (battery or the 12v buss on the firewall) to a relay, and switch the relay from an appropriate source on the fuze block.

That wiring is old, and some of it is already overloaded. Why add to the load?




acesneights1, that's really good info about the OPS. To add an override switch for priming purposes would be very simple.

Does the OPS interupt power or ground to kill the pump?

 

[Skinny]

Why not run a three position switch: ON-OFF-MOMENTARY

OFF would make a great theft deterrant
ON for the usual
MOMENTARY for bleeding

 

[MarcusOReallyus]

Hey, SneakerZed, just in case you are still with us , here's a post that shows the fuse box and what positions are hot & not. There's both a picture and a PDF diagram for your viewing pleasure.

http://www.steelsoldiers.com/showth...-not-working&p=1022465&viewfull=1#post1022465


So, to summarize what we've learned here:

1. Replacing the mechanical pump is the personification of evil and the worst crime any person could ever commit.
2. Some of us criminals don't see it that way, and a lot of folks have made the conversion and like the results.
3. The mech pump should be removed because running it dry will destroy it. Also, if you run the electric and mech in tandem, you risk a failure dumping diesel in your oil sump. That ain’t good!
4. The block-off plate is a standard Chevy 350 plate, available online anywhere from 6 bucks to 35 bucks, from eBay to Amazon and just about any place that sells Chevy parts. (I checked.)
5. If you get a chromed one, you are a tacky individual and should probably be shot.
6. Save the bolts from the pump for the block-off plate - they may be specific to the 6.2/6.5 block.
7. You can run power directly from a switched location on the fuse box. Lots of folks have done that with no problem.
8. Better yet, run power from a solid 12v source like the battery or the 12v point on the firewall (near the GP relay), to a relay, and then to the pump. Use the switched location on the fuse box to switch the relay.
9. If you want to get fancy, you can install an OPS (oil pressure sensor) from a later model 6.5 which will kill the pump if your engine quits. This is a safety feature in case of accident.
10. If you do that, you might want to install an override switch so you can use the pump to prime the system when needed. Figuring out the wiring for this is left as an exercise for the reader.

So there ya go. Lots of opinions, some solid info, and a good time was had by all.


Another two cents: You can use any fuel rated rubber hose, but if you want metallic pipe going through the engine compartment, consider using the cupro-nickel stuff. It’s sold under several brand names, and it’s very easy to use, and more corrosion resistant than stainless steel.

 

[Skinny]

That post pretty much sums it up, lots of options and lots of write ups to help you either way.

Don't forget to add:

11. If you complain that installing a new mechanical pump is hard, you are just a cotton headed ninny muggins

 

[dstang97]

OK I have to ask. Why change it to electric? I got to know why. The OEM pump is a breeze to change. My wife changed several of them just to prove she could do it. I was there giving her tips but she changed it in 1 hour. How easy is that? As a previous owner no fewer then 50 CUCV's I have never did any of these changes and see no reason to do so. That is my opinion. I drove my 1984 CUCV M1009 to Baltimore and back yesterday. And put 150 miles on it today. ALL Stock. Again my opinion. And I have been working with these trucks for 30 years. What do you gain? The OEM pump is $20. at Autozone and has lifetime warranty.

can you lend your wife out for a few months. I have a ton of stuff that's broken.. Lol your are a lucky man.