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Opel Tinkerer and Rescuer
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Discussion Starter · #1 · (Edited)
Just got a used double pumper from Gil...

Its jetting and such seems a bit off.. (Carb was sooty inside too).

Primary:
Fuel:132
Air: 175
Emulsion Tube : F66
Idle: 50

Secondary:
Fuel:127
Air: 145
Emulsion Tube : F66
Idle: 55

Seems close to the Otto sizing chart.. :)

Primary:
Fuel:135
Air: 165
Emulsion Tube : ??
Idle: 50

Secondary:
Fuel:140
Air: 160
Emulsion Tube : ??
Idle: 55

Seems on the one I have the fuel is a bit small on the secondary, same with air. Using the Otto Baseline.

Bob.. what jettings have you found work well in your Double Pump setups?

What about the Emulsion tubes?

Last but not least, what about the diaprahm for the sceondary pump.. looks like the main one but it is a bit different in that it doesnt have the piece for the lever to touch. Can I cut one down? OR do you know where I can get the part?

Charles
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #2 ·
One other thing.. I guess this is mainly for Bob since he has experience with the Double Pumpers..

The top gasket in the standard 32/36 is "Slightly" different than the double pumper.. There is a hole for the long tube in the top.. can I just cut a nothc in the other gasket and will that be good enough? Or do you have a source for the right gasket?

Charles
 

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GoinManta said:
Bob.. what jettings have you found work well in your Double Pump setups?
What about the Emulsion tubes?
Charles, I have no recollection of this. I only have one double pumper left, but I haven't seen it in years. I'll have to do a search. I do recall it needed a smaller secondary idle jet since the secondary accelerator pump squirter covered the void pretty well on its own.

Last but not least, what about the diaprahm for the sceondary pump.. looks like the main one but it is a bit different in that it doesnt have the piece for the lever to touch. Can I cut one down? OR do you know where I can get the part?
I do remember this part being different too....and at one time I was able order the correct part from Interco. I rebuilt a handful of these carbs in the early '90's, but they were rare...I think they were only made for two years in the mid '80's (the year is cast into the underside of the carb body).

The top gasket in the standard 32/36 is "Slightly" different than the double pumper.. There is a hole for the long tube in the top.. can I just cut a nothc in the other gasket and will that be good enough? Or do you have a source for the right gasket?
Now you're really reaching.....
I don't remember at all. I probably ordered a complete (proper) kit back in the day, but I doubt they're available now.

I remember the secondary accelerator pump vacuum hose being very sensitive to kinking or having a vacuum leak. If this happens the secondary pump doesn't open and the carb bogs big time.
But when it's running right and dialed in, these carbs are awesome. I remember you could floor the throttle from a standstill with a stock-engined automatic tranny Opel and it would not only pull cleanly without the typical bog associated with a progressive carburetor, but would spin the tires too.

I could look into the barn one of these days and try to find my last remaining double pumper to answer some of your questions.

Bob
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #4 ·
Thanks.. I am looking to see if I can find any anywhere.

I think I can modify the stock top gasket to work and modify a aceelorator diapragam to work.

Charles
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #5 ·
Since this thread will possibly be found byu others needing this info..

the two parts are parts numbers:

47407.115 - Seconadary diaphragm (Cost $10.17)
41705.040 - Upper Gasket (Cost $3.39)

Available through :

http://www.piercemanifolds.com/contact.html

They were great !..

BTW Gil at Opel GT Source has another rebuildable 32/36 double pump for anyone interested.
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #6 · (Edited)
One word for this carb... SON OF A B**** !!! My motor went from being over carbed with the 40FAV, to under carbed with a std 32/36.. To this carb... OMG.. All I can say is that the car spun going into 1st and 2nd and chirped the wheels going into 3rd. So Jetting seems perfect.. I think the sooty conditions of the carb when I got it were due to a cracked housing near the venturi. A small carck, but I am sure on that threw off the response of teh carb. I fixed it up with my dremel tool and some JB Weld. All seems excellent so far.

The difference with the 32/36 Double Pump is amazing... ! The motor in the Manta is strong, but has truly only had minimal work done to it and most bolt-on. It was rebuilt with AMC pistons to make it a high compression 2.0L, an Bob Legere intake, 75' exhaust, and that's about it.. This carb could not be better matched.

Know that the carb was not a "Special Edition" Weber, nor was it some wierd first edition as thought. It's actually a production carb from Weber for the Ford Tanus in europe. Which BTW was a 2.0L motor. I have pictures and such I will post shortly. Along with the blow-up of the carb, etc..

Similar to the 40FAV, the 40DFAV was built for 6 cylinder Ford of Europe cars. Both were not meant to be sold as aftermarket carbs. Which is why they are both rare. But if you can find a Ford Tanus/Cortina in Europe, you should be able to find this carb.

Charles
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #7 ·
Been driving the car to and from work recently.. having the extra pump on the secondary is even more noticeable at high speeds above 70. When you hit it at 70 you feel more power and acceleration, and its VERY noticeable.

Find attached the zip file of the blow up of the double pump.

Charles
 

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boomerang opeler
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GoinManta said:
Know that the carb was not a "Special Edition" Weber, nor was it some wierd first edition as thought. It's actually a production carb from Weber for the Ford Tanus in europe. Which BTW was a 2.0L motor. I have pictures and such I will post shortly. Along with the blow-up of the carb, etc..

Similar to the 40FAV, the 40DFAV was built for 6 cylinder Ford of Europe cars. Both were not meant to be sold as aftermarket carbs. Which is why they are both rare. But if you can find a Ford Tanus/Cortina in Europe, you should be able to find this carb.

Charles
i think these carbs were on the mk3 and 4 cortina S (sport) with the 2litre pinto engine and the escort RS2000 mk2 with the pinto. they are not on the sierra or granada/consol
 

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GoinManta said:
Been driving the car to and from work recently.. having the extra pump on the secondary is even more noticeable at high speeds above 70. When you hit it at 70 you feel more power and acceleration, and its VERY noticeable.
Charles, I'm not doubting your words that your car runs better, but you do realize that the secondary pump shot is only momentary, right? It only activates just as you crack the second throttle plate open. It does not continue to spray fuel from the secondary accelerator pump in the upper rpm range.

The 40 DFAV will make more power overall, IF correctly calibrated. It's probable that the 32/36 double pumper is just more closely jetted.

Bob
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #11 · (Edited)
RallyBob said:
Charles, I'm not doubting your words that your car runs better, but you do realize that the secondary pump shot is only momentary, right? It only activates just as you crack the second throttle plate open. It does not continue to spray fuel from the secondary accelerator pump in the upper rpm range.

The 40 DFAV will make more power overall, IF correctly calibrated. It's probable that the 32/36 double pumper is just more closely jetted.

Bob
I realize that, the 40DFAV was too much air, I didn't have the larger valves or Cam to take advantage of it. Duane recommended pulling it for a 32/36 because he thought is was too much carb for what I had. It bogged the motor, I had tried to jet it and with my limited jetting skills couldn't get it. Got it close but it was never quite right.

With the double pump it is the shot it what I notice in high end acceleration. It gives the engine a jolt improving its 70-75 or 75-80 times.. and then the engine is strong enough to hold the higher speed. With the other 32/36 carb when you hit it at high speeds it only gradually accelerated.

Same is true when going up the gears, each time you let up and shift you get a extra punch of acceleration at each shift...

Will admit the jetting is probably the best setup I have ever had with a 32/36 on any Opel. Which would explain the fact I got the Manta up to 95 (With more left in the engine) before I chickened out (Front end is a little lose, next project). With the other 32/36 I seemed to top out at 90 it still had some speed left, but it was slow to accelerate any faster.

Just checked and top speed for a UK 1.9L High compression Manta was 106 MPH, which I think my Manta is more than capable of (If I sort out the front end). I am going to have to dyno the Manta sometime soon ;)

It's a fun carb... getting the other one from Gil and going to rebuild it as well.. debating on putting it on the Blue Max or selling it. Because unlike the std 32/36 it has a connection for the vapor canister. So I can keep the Blue Max looking stock with stock emissions. The only one that will notice its a Weber are Opel owners, at local shows it would go unnoticed.

Charles
 

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Charles;
Is there a fuel line fitting on the second accel pump?
 

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I assume that it is just a port within the casting of the carburator.
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #14 ·
No it feeds from the fuel bowl. There were two major connections on the carb and I figured a way to hook them both up. Thinking the second was for the accelorator pump. To my surprise the one at the upper part wasnt a fuel connection but a vapor one (For a carbon canistor or something I assume).

So I had fuel shooting out the top of the carb at first :eek:

Fortunately it had no adverse affect on the carb itself, and once I plugged that one up it was fine.
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #15 ·
jordan said:
I assume that it is just a port within the casting of the carburator.
If you look at a std. 32/36 you will an emboss on the top (Thats where the vapor line would be), the empty square on the backside of the carb is where the secondary is located.

Charles
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #17 ·
Exactly like that, you would seem to not have the fitting for a vapor line on the top though. Not a big thing since I had to plug mine anyway.

What is the number after the 32/36 DGAV... Mine is a 18A.

To get the secondary diaphram, I have the part number in this post and pierce manifolds has them. Other than that it's a standard Weber rebuild kit.

BTW the two vacuum lines ports connect to each other (See diagram above)

Charles
 

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Opel Tinkerer and Rescuer
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Discussion Starter · #18 ·
Here are the pics.. Will take pics later when I rebuild the other one, along side a stock 32/36 to note the differences.
 

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