Weber 32/36: Fuel Pump Recommendations

[HondaBoy]

well i finally got the accord running with the new weber on it and fresh cylinder head. i set the timing just about as good as i can get it. also i've set the fuel as far as it will go. i think its not getting enough fuel. i havent replaced the fuel pump, it is after market but not beyond an OEM pump. i'll tell you what its doing. it'll idle ok, but slightly lumpy. when i give it WOT it boggs and doesnt want to rev up unless the throttal is somewhat gradually opened fully instead of all at one time. i dont think it is, but it may be the timing. but i do need to put a higher volume fuel pump.

i'd like a fuel pump that is going to flow more volume and not starve the carb at high rpms. i already have a fuel pressure regulator on it, that maxes out at 5.5 psi of fuel pressure. maybe this carb needs a bit more?

[2ndGenGuy]

From what I've read (I still run the stock fuel pumps on both my cars w/o regulators), the Holley Red fuel pumps are good. Anything high flow for carbs, but low pressure is what you want. Then set your FPR at 3 PSI.

[2oodoor]

yep the Weber does not like pressure over 4psi----starts to weep thru the top hat gasket, and causes fumes to affect the mixture.

Why do you think it is starving for fuel? Is your throttle cable allowing full travel of the throttle shaft.. common issue with these is the set up they give you in the kit barely opens the secondaries.

double check timing if you already haven't, if you can, use a timing light to see if it is going to full advance (in case the centrifrigal wieghts in the bottom of the dizzy are froze.)

[HondaBoy]

well as i have the distributor setup is just like i had it before when it would run the best. so i havent changed anything. it will fully advance. if i manually open the throttal, it still has the problem of bogging. so i dont know. i was told this wouldnt be too fun adjusting.

[2oodoor]

you can run more advance with this carb, makes a world of difference. Also you can use the vacuum advance conneciton closest to the dist body and leave the other one open or just cap it. Also you have to reset the dist timing any time you messed with the T belt which you had to do removing the head.
These carbs are very simple to adjust. You won't have to change the timing once you have it, but you may have to tiny tweak the mixture and curb idle to go with weather changes for optimal smoothness. Dont freak out , it is not a big deal at all. Takes every bit of one minute to do. If you later want to get fine tuned you can change emulsion tubes, and other jets, EASY again.. the hardest part is ordering the friggin pieces. This is a very simple carb.
Hopefully you do not have the T belt a tooth of or something though, and if you have ANY vacuum leaks, and it is common, you will have trouble getting the idle mixture constant.

[HondaBoy]

well i had really thought it wasnt getting enough fuel. wrong. but i did set the fuel pressure at 2 psi for now. i found the diaphram in the distributor advance/retard to be leaking between the two sides. what i did was take the vacuum line off, set the timing and its doing much better. but definately going to be something to do with that. might order a new one from work.

so as for the jets and emulsion tubes, they are pretty easy to take out and install? and how easy, would i just have to take the top of the carb off and there they are? if so i may do this sooner.

i'm just going to go head and get the new advance diaphram from where i work since there is a problem there. i'll see how things go from there. also will be seeing about a new fuel pump.

[2ndGenGuy]

Yep, just take the top of the carb off. The two jets on top are the air corrector jets, and under them are the emulsion tubes. I just pull mine out with a paper clip.

[2oodoor]

You can see them , and probably get them out without even taking the top of the carb out.
There is not a whole lot on the forum about this subject, I have found more info on yota forums. Anyway as for what the best combination of jets,tubes to use you will need to get an AF meter. Meanwhile you may not even need to do anything with it until you have driven the car and got to know exactly the carb some.

[cygnus x-1]

Don't buy a new fuel pump unless it's not maintaining pressure. What you're describing sounds more like a timing or mixture issue. Those vac advance diaphragms are notorious for leaking. I once went to the junkyard looking for advance diaphragms that didn't leak. Out of maybe 10 I checked, I found 1 that didn't leak. And it was for the wrong type of distributor.
But really what it sounds like is that the pump jet is too small. When you push the throttle the accelerator pump in the carb squirts extra fuel in to the mixture to compensate for the initial inrush or air. When the air velocity picks up the main jets kick in and supply the correct amount of fuel. If your pump jet is too small you will get a stumble when you first hit the throttle. Then after a second or so it will rev up like it's supposed to. One thing you can try to see if this is really what's happening is to pump the throttle 2 or 3 times before holding it down. That will dump in more fuel and help correct a lean condition. If you do this and the stumble gets WORSE, then it's actually too rich and you need a smaller pump jet. Do you happen to know what size the pump jet is? It might be listed in the paperwork for the carb.

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[HondaBoy]

i dont think it even said. it came with the most vague of instuctions and not much of anything else. but i did get it from a weber dealer. it was supposedly the right one for my car as it came in a kit specified for the A20.

i may look and see if i can find any specs on it. i've only found it to have the problem when the secondary is opened, no problems with the bogging when only the primary is opened. i'll see how things go after i replace the diapram on the distributor. i'm going to try and get one here in a couple of days.

[cygnus x-1]

i dont think it even said. it came with the most vague of instuctions and not much of anything else. but i did get it from a weber dealer. it was supposedly the right one for my car as it came in a kit specified for the A20.

i may look and see if i can find any specs on it. i've only found it to have the problem when the secondary is opened, no problems with the bogging when only the primary is opened. i'll see how things go after i replace the diapram on the distributor. i'm going to try and get one here in a couple of days.


That definitely sounds like you need a bigger pump jet then. You can also look at the jet to get the size. There will be a number stamped on the side. The pump jet is between the two barrels kind of off to the side; sort of a round piece with two legs sticking out. You *might* be able to see in there with a flashlight.

Keep in mind those kits are really only a starting point. Every engine is a little different. With a stock engine it should be close but still may need a little tweaking. Performance will also vary somewhat with temperature, so if it's cold outside you may be running a bit lean.

One final note, instantly burying the pedal when the engine is below maybe 2500RPM will probably always create a brief stumble. At low RPMs there isn't a lot of airflow through the carb so it won't react as quickly.

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[HondaBoy]

hmm. well i may order a larger jet for the secondary. i dont know if that will increase midrange power or not, but i was looking for more. also going to order a car sometime soon since i think i'm ready to do that.

[cygnus x-1]

If you're going to get into carb tuning I would suggest getting a wideband O2 sensor and AFR gauge. It takes a lot of the guess work out of it. You might also consider a jet kit, especially if you get into other mods like a cam and header.

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[2oodoor]

you could.. tune it to take WOT from idle and have it perfect.. but then you would lose something on the other end when you want to drive normally. Those carbs have a plug that blocks off the squrit from the accel pump jet into the secondary venturi. You could try taking the plug out I guess, but then when you want to drive on the primary only, which would be normal driving , you would have a build up of fuel on the secondary throttle plates going to waste. \
It looks like you could make these 32/36 into sychronous carbs like a 38/38 by changing a few things, like the linkage on the carb itself , the jetting, and the booster holders, and venturi inserts.