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Discussion Starter · #1 ·
Installed the electric fuel pump and it is working good. Ordered the block off plate and two gaskets per the cataloge. Gil or Dennis sent me two gaskets and a block off plate with a 1 inch hole on the middle. Now I have not taken off the mechanical fuel pump but it seems to me that a block off plate should be a solid peice of metal not one with a hole in the middle. Could some one verify that this is the right piece? :cool:
 

· Pathologic Opeler
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wrong one

i think you got a spacer to limit plunger travel in a mechanical pump.

the block off has no hole.i have one ,not installed yet and it is solid

ps:i will ship the disk tomorrow on the carb
 

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Discussion Starter · #5 ·
Matt M240Z said:
what reasons did you have for taking out the mechanical pump? bad pump? better fuel delivery? free power from running the mechanical pump?
The old mechanical pump was getting weaker and weaker and getting harder and harder to start- had to pump about 15- 20 times to get it started in the morning. Electric fuel pump- one pump and starts right up everytime. :cool:
 

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Discussion Starter · #7 ·
Graham said:
T Tom,

I have the same problem, can you give me the specs on the electric fuel pump?
Went to Auto Zone- told them I wanted a low pressure electric fuel pump ( 3 to 4.5 psi) $39.95 got a cheap pressure regulator valve set at 2.5 psi $4.95- works like a champ. :cool:
 

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if you have the equipment to do light fabrication. A fuel pump block off plate is diamond shaped. 32 mm or1.259 across the center, 70mm or 2.75 long, bolt holes at the long ends are 51mm or 2.0 to centers, holes are 8.6mm or .34. The plate is typicly 10 mm or .39 thick.

CSK (Checker, Shucks, Kragen) sell a good Purolator pump thats pretty quiet and works well with webers or Solex. OpelDean has the specifics on the pump.
 
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Search feature?

Rehashing old stuff here, but found the answer to ALL your questions by simply using the "Search" feature to find my earlier post on this topic, complete with pics even! :rolleyes:
 

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Mechanical fuel pump starting

baronbors said:
The old mechanical pump was getting weaker and weaker and getting harder and harder to start- had to pump about 15- 20 times to get it started in the morning. Electric fuel pump- one pump and starts right up everytime. :cool:
Did you mean "pump" the accelerator pedal or turn the engine over "15-20 times"? Unless it's leaking gas, don't think "weak" pump has much to do with your "hard starting". Other than leaks, mechanical pump is pretty much "GO/NO-GO" . . . works or doesn't.

Assuming mechanical pump, let's briefly review generally accepted "carb engine/mechanical fuel pump" starting method. You pump the accelerator pedal twice to "SET" (engage) the choke and "prime" the intake plenum, then start engine. If still using stock joined manifolds and, especially if not using a phenolic spacer and/or a carb heatshield (applies to ALL carbs!), unfortunately about all it does is set the choke! Let me explain.

Typically on engine shut down, much of the fuel in the carb bowl is evaporated due to heat soak from the exhaust directly beneath the carb plenum. That means there is not enough fuel remaining in the bowl and/or accelerator pump to prime the intake plenum properly when depressing the accelerator to "set" the choke.

If you're experiencing this problem, first correct the intake to carb stack-up if you're not using both phenolic spacer and heat shield. Trust me, Opel would not use these unless absolutely necessary (GM bean counters, remember?). In view of this, let me recommend a slightly different starting method for you.

Crank engine half a dozen times BEFORE depressing accelerator pedal to set choke and prime intake plenum. Pump will replenish fuel in carb bowl while cranking and then accelerator pump will be more likely to squirt some fuel into the plenum while setting the choke. TMO.

BTW and FYI, I don't have any "cold start" problems with my completely stock '69 Kadett with joined manifolds and Solex carb using the generally accepted and normally used "press accelerator pedal twice and then start engine" method.
 

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On all six original Opels (1 Kadette, 3 Mantas, 2 GTs) in our family since 1970 the starting sequence has always been the same, and never failed. Pump the accelerator pedal twice. Then insert the key into ignition switch. As you crank the engine, gently depress accelerator slightly. Fires smoothly every time.

We converted one GT to electric fuel pump. We key the ignition to energize the electric pump. Then flip the non-OEM switch to engage the starter. Don't mess with accelerator until engine has fired.
 

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Discussion Starter · #13 ·
tekenaar said:
Did you mean "pump" the accelerator pedal or turn the engine over "15-20 times"? Unless it's leaking gas, don't think "weak" pump has much to do with your "hard starting". Other than leaks, mechanical pump is pretty much "GO/NO-GO" . . . works or doesn't.
You are right unless you have a combination bad fuel pump and accelerator pump
Assuming mechanical pump, let's briefly review generally accepted "carb engine/mechanical fuel pump" starting method. You pump the accelerator pedal twice to "SET" (engage) the choke and "prime" the intake plenum, then start engine. If still using stock joined manifolds and, especially if not using a phenolic spacer and/or a carb heatshield (applies to ALL carbs!), unfortunately about all it does is set the choke! Let me explain.

Typically on engine shut down, much of the fuel in the carb bowl is evaporated due to heat soak from the exhaust directly beneath the carb plenum. That means there is not enough fuel remaining in the bowl and/or accelerator pump to prime the intake plenum properly when depressing the accelerator to "set" the choke.

If you're experiencing this problem, first correct the intake to carb stack-up if you're not using both phenolic spacer and heat shield. Trust me, Opel would not use these unless absolutely necessary (GM bean counters, remember?). In view of this, let me recommend a slightly different starting method for you.
[FONT=Comic Sans MS]I am- Dennis at OGTS set me straight on that point[/FONT]Crank engine half a dozen times BEFORE depressing accelerator pedal to set choke and prime intake plenum. Pump will replenish fuel in carb bowl while cranking and then accelerator pump will be more likely to squirt some fuel into the plenum while setting the choke. TMO.
Pulled the carb and re-jetted and re-built the Weber this week
BTW and FYI, I don't have any "cold start" problems with my completely stock '69 Kadett with joined manifolds and Solex carb using the generally accepted and normally used "press accelerator pedal twice and then start engine" method.
Now i just hit the pedal once to set the choke- turn the key and it starts right up
Question- I have the idle set at 1100 RPMs ( the engine just seems happier at that setting as opposed to 900 RPM ) and the cold idle with the choke closed is about 2000 RPM- is this normal or should i set the cold idle lower? :cool:
 
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