Facet electric fuel pump?

*more*

One thing I have to emphasize is that I have all those years and miles to make judgements and comparisons to the original Mikuni set up. For many years and hundreds of thousands of miles, that was my baseline. I've said this before, for all the rants I read about the original POS carb, when it's working right, it was awesome. "EFI smooth" is how I put it in another post. If I didn't have so many miles on the truck, it would prolly still be on the motor. It did not fail until 280,000.

These trucks are very honest though. When something is amiss, it will tell you with a symptom. Or try to tell you at least. Then it's up to you to piece it all together.

The parts manager recommended a Mitsu dealer tech that could possibly finish the install, but I've not gotten that far with him yet. He wanted to mount the electric pump under the hood. I never got that far with him but in hindsight I would say "well why are electric pumps almost universally mounted in the tank?" Because they need to be in the rear, that's why. But hey, I'm just a dumb-ass service writer. If I listened to him, I would have an even bigger cluster or even multiply my driveability issues.

A wise man once told me that he learned more about life in a conversation with a homeless bum than in many conversations he had with college professors with multiple PhDs. Is that why God gave us two ears, but only one mouth? You tell me.

I need to find somebody who will do this MY way. And I don't mean to sound snarky when I say that. Put another way, nobody knows this truck like I do. Even a veteran Mitsu tech has to respect that.

The dieseling or run on has been improved by 90%. The final 10% will be corrected when I finally get this system fully sorted. The return line fixed most of it, which is kind of why I'm so embarrassed, to be honest. At least I can turn the key off and it won't run on for more than a few seconds. That clutch and pressure plate got some serious abuse from popping that clutch to kill the motor. Since 2007. :shakehead:

I can feel some sloppiness in the drivetrain from that. But I'm not going to address that until this fuel system is fully sorted.

I really don't know what to say. I ask for input and thoughts, and what do I get? Nothing. Zilch. Nada.

I came here because I am just as passionate about these trucks as any of you, even more so in a lot of cases. I don't own one to do performance mods, because I drive one because they are so cheap to operate.

I'll just do what I think is best for me.

That said, I don't think this board will know how it worked out. I really want to share how my combination of parts will work, but if you guys don't really care, why should I?

Sorry guys.

Does this mean your not going to leave a tip? :)
Don't give up on the board...sometimes the right person for your question just hasn't arrived to answer it yet. We also try to emphasize that you do what is best for you. We always try to supply all the right tools to do the job, but it's hard to find all the right people to do every job. With your input, it helps make the board become more knowledgeable for the next person with a similar question. You may be that person that helps them.

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Originally Posted by BradMph

Does this mean your not going to leave a tip? :)
Don't give up on the board...sometimes the right person for your question just hasn't arrived to answer it yet. We also try to emphasize that you do what is best for you. We always try to supply all the right tools to do the job, but it's hard to find all the right people to do every job. With your input, it helps make the board become more knowledgeable for the next person with a similar question. You may be that person that helps them.

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Well that was kind of my point Brad. I ask for feedback for the P4070 and 12-804 pressure reg set-up, and all I get for almost a week is crickets chirping.

I'm like damn...

I guess I should have started a thread on intake icing.

I could jack-leg the shit out of it, but I was more interested in the regular user's thoughts on this particular set up- as opposed to "do what you want and let us know how it works out." I'm well past that point.

There is a right way and a wrong way to do just about anything, and since this is my truck we're talking about, I was sincere in asking for feedback in what I have planned. But sheesh all I hear is crickets. :(

Pretty sure this will work, all I'm looking for is a thumbs up or two...

Sorry man, but I have been slammed lately. Sometimes I can't get to all the posts. They come pretty hot and heavy at times.
As far as that regulator I had problems with it creeping up on the pressure. I tossed it and went with a return style. The other problem I have now is under heavy throttle I loose pressure and the system shuts off. But that is probably from fuel loss during acceleration. So I need to jam a hole bunch more foam in the tank or add in a fuel well with trap doors. Holly told me it was because I did not have enough restriction in the system,,,, Huuu??? I thought that was what the regulator did was make a restriction. So I added in a restriction jet in the return line so I'm double regulated.

Like Brad said some times we can't get to all the posts or people just don't have that part in there truck. I can't say anything on the pump. Never used that one. A majority of the time I'm on here is spent tracking IP addresses and blocking the spammers from China. So many times I only go off of what I see in the side bar. If it grabs me then I'll take a look or if it has zero replies I'll at least try to point them in the correct direction. This thread is a post 80 so I just figured it was being worked on by at least 3 or more guys. Sorry.

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Originally Posted by camoit

Sorry man, but I have been slammed lately. Sometimes I can't get to all the posts. They come pretty hot and heavy at times.
As far as that regulator I had problems with it creeping up on the pressure. I tossed it and went with a return style. The other problem I have now is under heavy throttle I loose pressure and the system shuts off. But that is probably from fuel loss during acceleration. So I need to jam a hole bunch more foam in the tank or add in a fuel well with trap doors. Holly told me it was because I did not have enough restriction in the system,,,, Huuu??? I thought that was what the regulator did was make a restriction. So I added in a restriction jet in the return line so I'm double regulated.

Like Brad said some times we can't get to all the posts or people just don't have that part in there truck. I can't say anything on the pump. Never used that one. A majority of the time I'm on here is spent tracking IP addresses and blocking the spammers from China. So many times I only go off of what I see in the side bar. If it grabs me then I'll take a look or if it has zero replies I'll at least try to point them in the correct direction. This thread is a post 80 so I just figured it was being worked on by at least 3 or more guys. Sorry.

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Don't take it the wrong way...it wasn't meant that way. From the set-ups I have been exposed to here, I haven't seen anyone yet with that set-up. A few are running the Carter P4070, but without a pressure reg. The ads say "No pressure regulator needed", but I'm calling BS on that as I mentioned earlier. The stock motor with that flow output- seems to me it would just nearly choke a stock motor with way too much fuel. If if reduces pressure by limiting a little flow, why is that a bad thing? It's 70gph for pete's sake. AND THE MOTOR IS STOCK.

I just really want to get this thing right. I've run it long enough with a stopgap fuel system in place.

It gets more than enough fuel with a stock pump and no reg and the stock pump max output is 4.2 psi. Running the stock pump with a real Weber for over a month has proven this to me.

The Carter P4070 runs 3-6 psi and that is way more pressure than needed- 4.2 is too much.

That is the crux of my question.

Inglese is the one who only recommends a Holley 12-804 with Webers. The last time I talked to him, he indicated he would try to answer any question I had. I may call him back and pick his brain a little more. I understand he would be guessing too, to be honest. An educated guess, but a highly educated guess is my take.

The holly regulator might work with the carter pump as it is a low pressure pump to start with. The one I used was a holly pump that builds 15 psi so I was forced to go with the return style regulator. The one that came in the box was just like the 12-804.
My pump is a holly blue and man o man does it pump fuel. The regulator that came in the box slowly creped up on the pressure thats why I went with the return style. It is 4.5 - 9 psi I must run 6 psi.

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Originally Posted by camoit

The holly regulator might work with the carter pump as it is a low pressure pump to start with. The one I used was a holly pump that builds 15 psi so I was forced to go with the return style regulator. The one that came in the box was just like the 12-804.
My pump is a holly blue and man o man does it pump fuel. The regulator that came in the box slowly creped up on the pressure thats why I went with the return style. It is 4.5 - 9 psi I must run 6 psi.

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From my research it looks like the 12-803 is 4.5-9 psi and the 12-804 is 1-4 psi. Both are adjustable within the stated ranges.

So you have the 12-803 in other words- but they look identical.

My feeling is- like I stated earlier the 12-804 seems tailor made for the Weber DGV on stock 4cyl. motors.

1) P4070 mounts is the rear on a mount made to fit one of the bed mounts. Electric fuel pump in the rear because it "pushes" fuel up to the motor. Use a stock filter before the fuel enters the pump, and you can also use the existing fuel supply line.

2) Mount the 12-804 on the LF inner fender. The 'bottom' of the reg is for the main line from the tank- (it is clearly labeled "in" whereas the other 3 fittings are labeled "out".)

3) Of those 3 outputs, one goes straight to the carb (I can easily put a simple in-line filter in that line,) one houses the fuel pressure mini-gauge that I bought, and the 3rd is just plugged off.

4) The return line is already hooked up to the carb.

That is the set-up I envision and that I think will work perfect on a stock motor.

Another part of the problem was the instructions that came with the counterfeit Weber. If I remember right, the instructions just said to plug it off. :bang:

That's where my 'run-on' problem came from. Hooking up a return line cured 90% of that problem- that's why I feel that the needle and seat is still being "over pressurized" and why I am still getting idle fluxuation in varying degrees.

I am still getting a slight degree of surging that I feel is idle circuit related as opposed to main circuit related. This will also be corrected when the system pressure is at or below 3psi.

Try 4-7 psi. 4-7 psi is better.

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Originally Posted by davidandrew

Try 4-7 psi. 4-7 psi is better.

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With a join date of today, I have to believe you are trolling.

Or may even be a regular user who is playing in his internet sandbox...

Troll.

the 12-803 look identical. Just different pressure. Of course what I have now is just larger in all aspects.

Engine run on is from the throttle plates being open to far at idle, and just a touch rich when you shut it off. IF it does not have the idle cut off solenoid it's a larger problem. Mine was that way. Many times a surge can be from being ether to lean or to rich. If it's an idle surge that is the problem and you need to preform the lean drop.

I have the factory Weber manual in the manual section in the first gen manual. But I would guess that the Webertation manual is a straight copy from weber.
Have you preformed a lean drop since you put on the new regulator? I want to say they describe it in the weber manual. If not it is in the UTI training manual with step by step instructions. There is also a thread on how to do it in the archive, and I might have placed it on this board at one time. Just search lean drop in the archive.
Then again there was no inter net when I hooked up my weber so I just ran the thing from the stock mechanical pump. Worked fine for me. But there were problems I never cared about.

My regulator is identical just higher pressure. If you don't have the bypass line does the pressure creep up on you tell it's at the pump max pressure. That was my problem. After about 25 seconds of running the pump the pressure would clime to 15 PSI.

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Originally Posted by camoit

the 12-803 look identical. Just different pressure. Of course what I have now is just larger in all aspects.

Engine run on is from the throttle plates being open to far at idle, and just a touch rich when you shut it off. IF it does not have the idle cut off solenoid it's a larger problem. Mine was that way. Many times a surge can be from being ether to lean or to rich. If it's an idle surge that is the problem and you need to preform the lean drop.

I have the factory Weber manual in the manual section in the first gen manual. But I would guess that the Webertation manual is a straight copy from weber.
Have you preformed a lean drop since you put on the new regulator? I want to say they describe it in the weber manual. If not it is in the UTI training manual with step by step instructions. There is also a thread on how to do it in the archive, and I might have placed it on this board at one time. Just search lean drop in the archive.
Then again there was no inter net when I hooked up my weber so I just ran the thing from the stock mechanical pump. Worked fine for me. But there were problems I never cared about.

My regulator is identical just higher pressure. If you don't have the bypass line does the pressure creep up on you tell it's at the pump max pressure. That was my problem. After about 25 seconds of running the pump the pressure would clime to 15 PSI.

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I'm still running the stock mechanical with no pressure reg. Most of the driveability issues I have have been greatly diminished with the Spanish made Weber install. But there are still a few niggling issues that remain.

Nobody here has that same setup, (stock 2.6, P4070, Holly 12-804) so I thought I might be on my own with it.

Trying to adjust the idle mix with too much fuel pressure is an exercise in futility. No other way to put it.

I do believe somebody was right when they said the Webers get real fussy with any fuel pressure over 3psi.

I don't have a fuel pressure gauge, but I would bet my left nut it's over 3psi. Everything else on the truck has worn minimally, I don't see why the mechanical pump would be any different.

Thanks for your input, Camoit.

The thing with the mechanical pump is it's a spring that makes the pressure. All the cam does is, reset the diaphragm so the spring can push it. I have seen springs do strange things. But your correct in thinking that you will be the first to have that configuration of parts. But to me a pump is a pump. It comes down to the flow it can run. A restriction is what makes the pressure.

Try the lean drop and see what it does with the set up you are using now. It may just fix all and then your done.

I know you don't want to believe it, but the mechanical pump will cause the problems you are having, and a reg won't fix it. The Weber is too sensitive to the pulsation of the mechanical pump because of its close proximity to the carb. If your pump is only putting out 3-4 psi, it is almost dead, as a new pump puts out 9-13 PSI. I have run Webers for over 30 years, and installed them on several trucks - if you want the rest of the issues to go away, go with an electric pump - you won't regret it.

P4070, Holly 12-804

I have that exact same device setup, lol. Your not alone in this world. Though I run a 2.0L engine with a header but shouldn't make a big difference. I also had to adjust the pressure on the regulator to almost full open to get the proper pressure and flow I wanted. I also removed the 2nd fuel filter I put in right in front of the carb. It was a glass see through one that friggin unthreaded itself because of a bad thread tapping job at the parts factory and I'm sure could of burned the truck down. Stupid manufactures.

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Originally Posted by pennyman1

I know you don't want to believe it, but the mechanical pump will cause the problems you are having, and a reg won't fix it. The Weber is too sensitive to the pulsation of the mechanical pump because of its close proximity to the carb. If your pump is only putting out 3-4 psi, it is almost dead, as a new pump puts out 9-13 PSI. I have run Webers for over 30 years, and installed them on several trucks - if you want the rest of the issues to go away, go with an electric pump - you won't regret it.

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Pennyman, I have a factory shop manual for 1989 and it says that the factory pump puts out 2.4-4.2 psi. (Page 14.2 in the factory manual.) However that is equivalent to 20-29 kPa or the metric measurement as you know.

But I think you're right, the proximity to the carb is the problem, not the psi that the stock pump delivers.

I've already bought both the 12-804 and P4070- I am just waiting for my chosen wrench to finish putting up his shop. He's doing the metal building thing- the slab has been poured and he's in the process of getting the building. He already has a lift.

Thanks for all of your inputs guys.

I can't help it these original parts on these things last forever. LOL

Don't forget the flow the pump can put out. I wonder what the flow in GPH is on the stock pump. An electric pump will have a higher flow.

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Originally Posted by camoit

Don't forget the flow the pump can put out. I wonder what the flow in GPH is on the stock pump. An electric pump will have a higher flow.

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The Carter is 70 gph. The shop manual does not specify a specific fuel output for the factory pump, just the outlet psi.

70 gallons per hour for non-EFI should be plenty for this application.

I need to check with Mitsu and see if the fuel pump gasket is available separately. If it is, I can use it to have a cover plate made where the factory pump is mounted. I have leftover sheet steel for the electric pump mount. I only used half of it. :thumbup:

Rockauto.com has the stock gasket. You can get them from NAPA also.

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Originally Posted by camoit

Rockauto.com has the stock gasket. You can get them from NAPA also.

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If those two parts outlets have it available, then I should be able to get it through CarQuest.

Thank you.

Ummm So how did this end? Did the parts get installed? Are the problems gone? :shrug:

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Originally Posted by arford

Ummm So how did this end? Did the parts get installed? Are the problems gone? :shrug:

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Go to the 2nd Gen electric pump install thread. It ended well.

IMO that thread should be pinned but what do I know.

Try to ask for help or give help and you get treated like an interloper.

That's been my experience. Not in the clique I guess. Or more likely the owners of this site really don't care that much.

I wanted to put up a thread about what I learned in jetting and adjusting the Weber carb but the reactions to what I have put up so far are so tepid I don't even want to bother. It's why I had to figure it out myself for the most part. Then you try to help others and the thread gets buried.

I feel like I am talking to myself most times.

Sorry for sounding so harsh but it's true.

Much sympathy here, seen and experienced a bit of that myself.

lol I am new and I've experienced crickets to my posts for help as well. LOL

I guess its just the way things are..

I'm glad to see that everything went well and I will be taking a similar trip as you did with converting to a weber/electric pump/Regulator set up soon.

Only question I have is that I have seen mention of an addition of an "Oil Pressure regulator switch" Why do we need to install one of those?
Does it replace the oil pressure idiot light in the dash, or can i just omit that part of the conversion?

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Originally Posted by Kaos731

lol I am new and I've experienced crickets to my posts for help as well. LOL

I guess its just the way things are..

I'm glad to see that everything went well and I will be taking a similar trip as you did with converting to a weber/electric pump/Regulator set up soon.

Only question I have is that I have seen mention of an addition of an "Oil Pressure regulator switch" Why do we need to install one of those?
Does it replace the oil pressure idiot light in the dash, or can i just omit that part of the conversion?

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The oil pressure cut off switch accomplishes 2 things-

1. It will turn the pump off if (God forbid) you get in a wreck and are unable to switch the ignition key off. In other words it turns the electric pump off when the oil pressure drops to '0'. It does not affect the warning lite or gauge depending on what you have.

2. It's nice to have one if you are sitting in the truck for a period of time and want to listen to the radio w/o the engine running.

They are both good reasons to have a oil pressure cut-off switch installed but I just haven't gotten around to doing it yet. I am on disability from strokes so the truck is not used that much but I will get around to it eventually as 'something to do' LOL.