I finally had my fill of FI and ripped out the entire fuel injection in 30 minutes. I was finally able to clean my engine out nice Installed dual weber carbs. I'm going to hold on to my fuel injection if I ever change my mind or sell.

Question. I installed a new low pressure fuel pump so my lines are empty. When I turn the key, I can't hear it like my FI fuel pump. What is the best way to prime these when they are new?

Everything is hooked up except for the throttle cable. Should I disconnect the fuel lines to get the air out of lines. I do not know if these are vacuumed or not is why I am asking.

What carbs?

Is the pump actually running when you turn the key on?

With carbs, when the pump is running it will deliver fuel to the carb float bowls. Any air in the lines will pass through to the float bowls and out of the float valve. Once fuel follows the air then the float bowls will fill with fuel and the float will shut off the flow. A double pump or two on the throttle will result in fuel coming out of the accelerator jets

However, if you wired up your fuel pump where it only runs when the coil is producing power (like the FI does, and is a good safety feature) then you'll have to add a manual switch to turn on the pump to do the above. Or, you wire the fuel pump to also run when you're cranking the engine (the like FI does).

On crap....we're back to wiring again. Have to put the FI back on

No need to remove lines,if setup right it will self prime after cranking for a while ,have you wired the pump via SirAndys method in the info section ?.
Pull your negative from the coil and crank over using a remote starter switch or second person on the key,you can check for leaks than way...safer than when its running.
Good luck.

I think you just used the stock wire for fuel pump but did not do some modification to get power supply to that fuel pump wire. FI will give the power supply to that wire.

I did not change the setup with the wires to the existing fuel pump. I used the same ones I had in my high pressure pump from the fuel injection.

I just don't hear this fuel pump like I did my other fuel pump.

What type of pump did you install? Rotary or facet? It doesn't take much to build 3ish lbs of pressure. The rotarys are very quiet. With the key on, not running, operate the linkage fully by hand a few times while looking down the carbs for fuel exiting the pump jets.

The pressure is VERY different. Like 30psi vs 5. Hopefully you swapped appropriate pumps. Glad you saved it because learning and understanding FI is so worth it.

I don't know which but it is suppose to produce 3.5lb max. Got from Pelican but it is CB Performance pump. I will give try pumping the linkage and see if I get anything. Nothing so far.

Oh I know that. It is definitely 3.5lb psi. I did the swap to start driving. After ripping everything out, it has to be my wiring harness or MPS or both was my problem. Every other option was exhausted. Dr914 offered to check my MPS which I will mail to him.

If not done do Andy's ground wire between the relay board and chassis mod. The board relay And fuse need to be place. If only to get it running. the pump will be activated continuously but stop running after the pressure builds. 3 full pumps and a bit of throttle feathering it should come to life. Did you get the CB Weber book when you bought the pump?

"Dr 914" is here to sell you parts. You are already on this forum, he should just answer up instead of asking you to mail him stuff. Why do you think you need an MPS with carbs? And why would a self proclaimed expert ask you to send him an FI part to troubleshoot your carb problem?

I think this is your problem. Go back to what @ndfrigi said in post #5 and then look at this article: http://www.914world.com/specs/SirAndyCarbFuelPumpRelay.php The ECU for the FI is what turns the stock pump on. With that gone, you have to do the simple mod to get your fuel pump relay to kick on.

I was just coming up to ask that.....My fuel injection harness is gone so I probably have no power to my fuel pump. Thanks for the info! I will look that up.

I still want an explanation to why MPS was even brought up regarding a carb conversion.

Yes. No pump power right now.

Don't believe that will work as the jumper lead (earth) you will need to fit to body as per that DIY supplies power that would normally be covered by the FI harness which you no longer have,reason you don't hear the pump.

It was an issue with the FI I was having. Has nothing to do with the carb setup.

Ok, I connected the 4 pin to the ground as mentioned per the sirandy info and now when I turn the key, I hear the pump. Now I have gas but trying to crank her, I have flames in one or both the carbs. A little scary. She won't start but I'm not pushing her. Only got my 10 year old daughter turning the key as I play with the throttle.

Are the jets not spraying is my only idea?

Did you set the float levels on both carbs when you installed them? First thought is that maybe the float valves aren't shutting off fuel when the bowls are full. Beyond that, I'll leave it to those who actually know something about carbs.

Model of distributor? Go through the setup procedure.

No, no, no.....This is when I had my FI installed. I was trying to narrow down an issue. Sorry I ever brought it up. My MPS has nothing to do with this thread.

I purchased a Dansk distributor from Pelican.

I am now thinking my timing is off. I am getting gas but not firing in sequence. I have no idea how to check timing.

Carbs are king

180 out

Post how you have it wired?

The Dansk from pelican is the quivelent of a 009? Is there a notch on the top edge of the distributor body at what should be cyl #1?

I'm not seeing a notch. That is probably my problem. My plug wires may not be firing in correct order. I wired like my last distributor had them but this one may be different.

I have it wired the same way my FI distributor wires were.

No. 1, 4, 3, 2. Review chapter 3 of your Haynes.

Your FI fuel pump wires were energized/grounded by the FI ECU via the relay plate.

No worky for carbs.

I know. I did the SirAndy info for converting over to carbs with the extra ground wire. My pump runs now when the ignition is turned and cranking. However, it doesn't want to shut off when the key is turned off. I have the pull the plug off the no. 4 pin.
http://www.914world.com/specs/SirAndyCarbFuelPumpRelay.php

Will do...Thanks!

Edited noon for errors.


That doesn't make sense.

Per that link and its accompanying photo, you're actually grounding the T4b III circuit, "third" wire, which grounds the fuel pump relay solenoid, closing the circuit for the power side of the fuel pump. The power side of the fuel pump circuit comes from fuse S13, which is energized directly from the battery. That's why the pump comes on.

The fuel pump relay gets actuated by power through the power supply relay (PSR). The PSR is only hot with the key on, through fuse S9.

If your fuel pump is running with the key on, then that implies to me that there's an issue with your PSR circuit or your fuel pump circuit.


For reference, T4b-IV ("fourth" wire, bottom left in that photo) gets power when the ignition switch is in the "Start" position. If you ground that terminal it'll short circuit during cranking.

Unless I'm misunderstanding something?

Note that these are based off of my 1974 electrical diagrams.

go by the picture

With key on and pump running, pull the fuel pump relay. Pump should stop running.

With key on and pump running, pull the power supply relay. Pump should stop running.

Do both tests with key off.

Report results.

#1 - you need this jumper on your relay board (lower left):




#2. - you need to get a fuel pressure regulator and gauge and set the pressure to 3psi max.

My dual Weber 44's run fine with the above.

GN

Fuel pump relay pulled, pump goes off.
Power supply relay, pump stays on.

No bueno. You either have an internally-shorted relay plate or someone has been messing around with your wiring. With the power supply relay removed you should not be getting power to the fuel pump relay solenoid Pin 85 and/or relay plate pin T4b-I, the upper right in that photo above, both on same circuit.

Edit: here's a screen capture of the circuit. You can see when the PSR J16 is removed, there's no way for the fuel pump relay (J17) to get +12V at pin/circuit 85. Without that, grounding T4b-III wil have no effect on the fuel pump circuit (30 to 87; connector TT14-13 goes to fuel pump).

Edit 2: is there anything connected to the T4b-I pin, the upper right one next to the grounding wire you installed?

Click to view attachment

Well it was cool of George to try and help, wouldn't you agree Rand?

I will work on the fuel pump not shutting off after I get this thing started.

My rotor goes clockwise and I have my plug wires firing in order. Is it suppose to fire off the #1 plug first every time and then move on to the #4, #3, #2?

I am getting backfires through both carbs while cranking. Does this mean I am not getting enough fuel? I have not adjusted either carb. From what the instructions showed, she should start and then you can fine tune.

Figure out where TDC on cyl #1 is. Use the engine cooling fan mark(s). What ever location the rotor is pointing to, respective of the cap terminals, should be where the #1 plug wire goes.

For the pump. Have a look at the classic thread forum and read andy's write up. Do it exactly the same way. It works.

the ground needs to be #3 not #4 as before mention.. to work with carbs ..
the second version pictured works for him , but the norm is ground #3

So basically, pull the black plug on the cooling fan and keep just slowly turn the ignition until I see the mark on the fan. Then look at the rotor button. That will tell me the #1 cylinder......Do I have that correct?

sounds like you need to static time engine from the beginning. turn engine until tdc on #1 on compression stroke. both rocker arms loose. rotor should be pointing at #1. if it is not, reclock distributor so that it is. check points are just opening with test light. replace cap, wire # 1 goes on that terminal, #4 wire next to it, #3 next and finally #2. that should get you close enough to start it. then time with a light once running. my carbed 1.7 runs best at 34 degrees btdc. the timing is set off the cylinder/stroke position, not distributor position. if distributor is clocked incorrectly you will be off.

Did you turn your engine over to TDC#1 before you started? If not then your distributor is probably improperly indexed/timed with TDC#1.

If you don't know where TDC#1 is, read the workshop manual for further clarification. At TDC#1 #1 piston should be at the top of it's stroke, and both valves should be fully closed, if you're not sure, then take the valve covers off and confirm. Also the rotor should point towards the front of the crankshaft.

No, I did not. This is a learning experience. I am trying to find the TDC mark now. I will post back when I do and see how things go from there.

Working on this now and will post back.

I found the TDC on my fan. Saw where my rotor button was pointing. Installed the cap and put the #1 spark plug wire to it, then #4, #3,#2.....Turned the ignition and SHE STARTED!!!!!!!!!

She runs a little rough but now I can fine tune it. This is awesome....Thanks so much guys.

Now I have to work with this fuel pump staying on.