Fuel pump conversion questions....

[ccole]

Hello all-
Have a question regarding my 1984 6.2 Chevy.... For a couple months now, it has been acting up; surging at stop signs, hard starts when engine is warm, very difficult to re-prime engine after fuel filter change. I suspect the mechanical fuel pump has finally failed.
I have heard talk of replacing the mechanical fuel pump with an electric fuel pump and have a couple questions regarding this upgrade. First, what pump do you guys prefer? Something such as the red holley? Also, where do you locate the pump and tap into the curent fuel lines? My last question is what do you do with the mechanical fuel pump? Leave it on truck and leave the plumbing alone or is something else recommended?

Thank you!

[Mr. Bone]

Hello,

I suggest a thread search on the subject. I think you'll find lots of helpful info.

Best.

[ccole]

Replaced the lift pump with a replacement last night. Wow....that rear bolt holding the pump in place was tricky. Pretty safe bet that next time I will replace it with a electric inline fuel pump.

[bbbear]

Replaced the lift pump with a replacement last night. Wow....that rear bolt holding the pump in place was tricky. Pretty safe bet that next time I will replace it with a electric inline fuel pump.

Sounds like hard work. Since I'm a lazy guy, I intend to replace my mechanical pump with the inline Autzone electric pump, part # E 1101 S, $49. However, unless someone can tell me why I shouldn't do it, I'll leave the mechanical pump in place and simply by pass it. I'll also loop the mechanical pumps fuels lines by connecting the ingoing fuel with the outgoing fuel..
The following is a picture of the Autozone electric pump alongside some gp heaters I'm putting together: http://www.kodakgallery.com/Slideshow.jsp?mode=fromshare&Uc=6ct8bbj.2l6r829b&Uy=-7i6w3w&Ux=1

[DmaxMaverick]

Sounds like hard work. Since I'm a lazy guy, I intend to replace my mechanical pump with the inline Autzone electric pump, part # E 1101 S, $49. However, unless someone can tell me why I shouldn't do it, I'll leave the mechanical pump in place and simply by pass it. I'll also loop the mechanical pumps fuels lines by connecting the ingoing fuel with the outgoing fuel..
The following is a picture of the Autozone electric pump alongside some gp heaters I'm putting together: http://www.kodakgallery.com/Slideshow.jsp?mode=fromshare&Uc=6ct8bbj.2l6r829b&Uy=-7i6w3w&Ux=1


How do you intend to address the need for a failsafe? You may be in for more expense/hassle than just replacing the mechanical pump. They're not that difficult.

[bbbear]

How do you intend to address the need for a failsafe? You may be in for more expense/hassle than just replacing the mechanical pump. They're not that difficult.

I don't trust that particular mechanical pump. It could get a small tear in the diaphram and have little to no symtoms while pumping fuel into the crankcase oil. Not good. I merely intend to use the existing mechanical pump to block the hole. ( Do you see any problems with that? You know, looping the lines on the mechanical pump?) An electric pump makes for easier starts and is much easier on the starter, as well as the driver's sanity when searching for air leaks, bleeding the system, or changing filters, etc..

Thank you for initially bringing up the notion of a failsafe. I learned a lot about how various systems might work. It was fascinating. I even brought it up on another forum. After a lot of thought, were I burning gasoline, I'd certainly go for a failsafe and figure some way to run the electric pump's ground wire through the oil pressure guage. But since diesel and WV0 are not that easy to ignite, a failsafe is no longer in my plans. As it is, the left hand tank is diesel and used for starting, and the right hand tank is WVO which is flipped on when the engine is warm, and used 95% of the time.

Of course it can be done, but trying to ignite WVO is akin to trying to ignite molasses. Diesel also takes a bit to light it up.

Still, were I a professional trucker, like many here, who daily pull heavy loads through rugged terrain, I just might install a failsafe.

[DmaxMaverick]

Sorry. Not good enough to discredit the mechanical pump. If you don't want one, don't use one, and leave it at that. In all the near 100 years the mechanical pump of current discussion has been standard equipment until recent models, can you recall the incidents of crankcase oil contaminated with fuel due to the pump? You are more likely to trash a $1500 IP, among other things, with a failed electric fuel pump, especially a cheap $49 pump.

The failsafe......
Your choice to omit it is your choice. It is not legal, regardless of the fuel, be it gasoline, Diesel, or WVO. Even antifreeze doesn't burn, until it does (it will). The problem is not only combustion, or the combustibility of a fuel. The last thing you need at a traffic collision is fuel, of any kind, spraying all over. #2 or WVO will burn just a hot as gas. BTW, the vast majority of drivers/passengers involved in traffic collisions are not commercial drivers or vehicles. They are the very vehicle you describe as your category. Ask your insurance company their take on it. Get involved in a crash and pump fuel all over the scene, you will be responsible for all that occurs because of it, civil and criminal, and your insurance company won't shed a tear for you. Bypassing or omitting the failsafe would be irresponsible. According to your descripiton of your WVO system, you are already there.

[john8662]

The AC-Delco replacement pump is the good one for the 6.2.

I've tried the Carter replacement mechanical pumps, I had one fail in short order, well lasted 6 months.

The AC Delco it replaced was original, and it was one of those "since yer there things"

With that said, I have great faith in the Mechanical fuel pump, as it is very reliable, and quits pumping when the engine quits running.

With a few fuel pressure tests I have also found that the mechanical pump supplies more fuel that the standard electric pumps. Also, intersting is that it makes pressure almost instantly at start, if the fuel system is leak free of course.

But...

I do like the electric pump placed inline before the main pump that can be operated in the engine bay or cab for fuel priming on a momentary switch, to be used only for priming.

This came in handy when someone (no names) tested to see how far his formerly fuel efficient '82 pickup would go on 1/8 of a tank. Needless to say, E probably meant E for a reason. I heard that he had to call his Girlfriend to come get him in her *cough" Honda car to go get some Diesel fuel. At least the priming was easy...

eh.. oops!

I think a failsafe with an electric pump is necessary as mentioned above, not only for the fire hazard, but for the sake of the mess it could potentially create!

If converting to the electric pump, I'd recommend looping the lines where the Mechanical pump resided (don't cut lines, just get hose over the flare on the threaded side) and bypass the pump.

The conversion can be completed then by removing the pump from the engine completly, with it's matching block plate and push rod, then replacing it with a standard fuel pump block off plate.

Block off plate?

Yep, ANY SBC (like a 350 for example) shares the same pump pattern, buy a SBC block off plate, make it Annodized blue maybe?

J

[bbbear]

Sorry. Not good enough to discredit the mechanical pump. If you don't want one, don't use one, and leave it at that. In all the near 100 years the mechanical pump of current discussion has been standard equipment until recent models, can you recall the incidents of crankcase oil contaminated with fuel due to the pump? You are more likely to trash a $1500 IP, among other things, with a failed electric fuel pump, especially a cheap $49 pump.

The failsafe......
Your choice to omit it is your choice. It is not legal, regardless of the fuel, be it gasoline, Diesel, or WVO. Even antifreeze doesn't burn, until it does (it will). The problem is not only combustion, or the combustibility of a fuel. The last thing you need at a traffic collision is fuel, of any kind, spraying all over. #2 or WVO will burn just a hot as gas. BTW, the vast majority of drivers/passengers involved in traffic collisions are not commercial drivers or vehicles. They are the very vehicle you describe as your category. Ask your insurance company their take on it. Get involved in a crash and pump fuel all over the scene, you will be responsible for all that occurs because of it, civil and criminal, and your insurance company won't shed a tear for you. Bypassing or omitting the failsafe would be irresponsible. According to your descripiton of your WVO system, you are already there.

Since I got the notion of the cheap electric pump from Autozone, part # and all from one of Dr. Lee's modifications, I suggest you take it up with him.

[bbbear]

The AC-Delco replacement pump is the good one for the 6.2.

I've tried the Carter replacement mechanical pumps, I had one fail in short order, well lasted 6 months.

The AC Delco it replaced was original, and it was one of those "since yer there things"

With that said, I have great faith in the Mechanical fuel pump, as it is very reliable, and quits pumping when the engine quits running.

With a few fuel pressure tests I have also found that the mechanical pump supplies more fuel that the standard electric pumps. Also, intersting is that it makes pressure almost instantly at start, if the fuel system is leak free of course.

But...

I do like the electric pump placed inline before the main pump that can be operated in the engine bay or cab for fuel priming on a momentary switch, to be used only for priming.

This came in handy when someone (no names) tested to see how far his formerly fuel efficient '82 pickup would go on 1/8 of a tank. Needless to say, E probably meant E for a reason. I heard that he had to call his Girlfriend to come get him in her *cough" Honda car to go get some Diesel fuel. At least the priming was easy...

eh.. oops!

I think a failsafe with an electric pump is necessary as mentioned above, not only for the fire hazard, but for the sake of the mess it could potentially create!

If converting to the electric pump, I'd recommend looping the lines where the Mechanical pump resided (don't cut lines, just get hose over the flare on the threaded side) and bypass the pump.

The conversion can be completed then by removing the pump from the engine completly, with it's matching block plate and push rod, then replacing it with a standard fuel pump block off plate.

Block off plate?

Yep, ANY SBC (like a 350 for example) shares the same pump pattern, buy a SBC block off plate, make it Annodized blue maybe?

J

Thanks for the adult approach and the great info. As I said, I got the info from an article by Lee Swanger aka The Clevite Kid. It's titled, Electric Lift Pump and Racor Filter for the early Diesels-and a Performance Update. However, Lee left the mechanical pump in place and installed a dash switch for the electric pump... After reading your suggestions, I'll probably do the same. That is, use the electric pump for bleeding and starting, then switch off and let the mechanical pump do its job. Oh yes, that was the wrong part #. It's E 8012 SM. Lee paid $39. for it about 10 years ago and chose it over the more expensive AC pump at half the price.

[Robyn]

I have a set of bolts that will scew into the fuel pump bolt holes that have the heads removed.

The trick is to rotate the engine by hand until the push rod is as far into the engine as possible. Sit the pump into the aperture in the block so the pump arm is under the push rod.
Install the two long bolts as pilots and then work the pump in and then replace one of the studs with the original bolt and then with that one just sort of snug do the other bolt and poof your done :D

Learned that trick after I learned all the colorful metafores by trying to do it without the alignment studs. :rolleyes:

best of luck

Robyn

[bbbear]

I have a set of bolts that will scew into the fuel pump bolt holes that have the heads removed.

The trick is to rotate the engine by hand until the push rod is as far into the engine as possible. Sit the pump into the aperture in the block so the pump arm is under the push rod.
Install the two long bolts as pilots and then work the pump in and then replace one of the studs with the original bolt and then with that one just sort of snug do the other bolt and poof your done :D

Learned that trick after I learned all the colorful metafores by trying to do it without the alignment studs. :rolleyes:

best of luck



Robyn

Excellent tip! Thanks Robyn.