Got a few Questions hopefully someone can help me out with ,I got a major flat spot on acceleration the book (Gregorys) says it may be
a,Blocked accelerator pump discharge jet or sticking check valve
b,Faulty accelerator pump plunger washer
c,Faulty accelerator pump linkage
I have looked at the pump linkage and it appears to be fine ,replaced the plunger washer which had a tear in it but still didnt fix it so process of elimanation says it has to be A discharge jet or sticking check valve.
Now my first question ,Is the discharge jet located next to the main jet& same location as the check valve.2nd i probably need a jet removing tool where do you find these. 3rd should i be using a ek manual instead of a gregorys (more detail)?thanks D
Flat spot on Acceleration
D61,
Firstly, try this tip:
Remove the air filter assy, Get the engine up to temp, whilst the engine is running, place your hand completly over the top of the carby, then at the same time give it a couple of full throttle revs. Don't be to frightened that the engine vacuum will suck your hand in, it won't. It will just leave a slight ring around your palm for a couple of mins.
This method will do 2 things: It will tell you if you have enough fuel, as it will be on the palm of your hand. It will also clear loose partial blockages in the main jet and power valve circuit.
If the flat spot is still there, then maybe your accel pump plunger is not sealing or there is a blockage in the port.
To find whether there is blockage there, turn the engine off and with a torch peer down the throat of the carb, and work the throttle. You should see a stream of fuel discharging from the accelerator pump plunger circuit. The stream will only be of short duration, and similar to a standard spray bottle pattern but not as long.
You may only get around 5 full pumps before the float bowl empty's, so don't be alarmed if you see run out, or not work all of sudden.
If there is no action there, check under the float bowl on the outside of the carby and see if the little u linkage is still intact and operational with the throttle, maybe it is that worn it is no longer operating, or the spring retainer has come off and has disconnected itself., for memory there are three holes, and the position of the pump plunger should be in the centre hole.
On the inside of the carby that rod goes to the accel pump rod, where there is a little circlip that holds the spring on the pump plunger in situ, maybe this circlip has come adrift also. Removal of the top air horn will be required to find out if it is still connected there.
If you replaced the pump plunger already, did you note if it was a leather type or plastic. If it is leather then you need to soak it Auto trans fluid for around ten minutes to soften, then tease it out slightly to provide a good seal in the chamber.
If it's the plastic type, lubricant is required before installation as well.
If no fuel is present there still, then the main supply port is blocked in the float chamber, where the check ball sits, if you go this far, you may aswell pull the carby of and rekit it.
Regards John
Firstly, try this tip:
Remove the air filter assy, Get the engine up to temp, whilst the engine is running, place your hand completly over the top of the carby, then at the same time give it a couple of full throttle revs. Don't be to frightened that the engine vacuum will suck your hand in, it won't. It will just leave a slight ring around your palm for a couple of mins.
This method will do 2 things: It will tell you if you have enough fuel, as it will be on the palm of your hand. It will also clear loose partial blockages in the main jet and power valve circuit.
If the flat spot is still there, then maybe your accel pump plunger is not sealing or there is a blockage in the port.
To find whether there is blockage there, turn the engine off and with a torch peer down the throat of the carb, and work the throttle. You should see a stream of fuel discharging from the accelerator pump plunger circuit. The stream will only be of short duration, and similar to a standard spray bottle pattern but not as long.
You may only get around 5 full pumps before the float bowl empty's, so don't be alarmed if you see run out, or not work all of sudden.
If there is no action there, check under the float bowl on the outside of the carby and see if the little u linkage is still intact and operational with the throttle, maybe it is that worn it is no longer operating, or the spring retainer has come off and has disconnected itself., for memory there are three holes, and the position of the pump plunger should be in the centre hole.
On the inside of the carby that rod goes to the accel pump rod, where there is a little circlip that holds the spring on the pump plunger in situ, maybe this circlip has come adrift also. Removal of the top air horn will be required to find out if it is still connected there.
If you replaced the pump plunger already, did you note if it was a leather type or plastic. If it is leather then you need to soak it Auto trans fluid for around ten minutes to soften, then tease it out slightly to provide a good seal in the chamber.
If it's the plastic type, lubricant is required before installation as well.
If no fuel is present there still, then the main supply port is blocked in the float chamber, where the check ball sits, if you go this far, you may aswell pull the carby of and rekit it.
Regards John
There's nothing as Sweet as a EK V8
Thanks John for the quick reply ,just as you said putting my hand over the carb and giving it a few revs was enough to clear it of blockages 
It is always good to pick up on any little tricks , I picked up a jet removal tool off ebay for future use anyway.So does the ek manual have heaps more detail compared with the gregorys and worth getting myself one?
Thanks D
It is always good to pick up on any little tricks , I picked up a jet removal tool off ebay for future use anyway.So does the ek manual have heaps more detail compared with the gregorys and worth getting myself one?
Thanks D
GMH manual
Hi D,
John has put the acid on this - thanks John - (Stewart has opened up an opportunity to store information and advice such as yours within the tech section - we probably need to spend a few weeks re-formating material both new and existing and when satisfied - have it "stickied"........)
D-
I have various workshop manuals of all Holdens up to HR - The factory ones I find to be more helpful - the generics, although quite informative, fall a bit short in some areas - I would suggest to anyone to try and get a factory manual - just don't loose an arm for it.
Of course, your best source of info is either here, or within a club.............
This site is supported by many, many experienced and capable members, most of whom are more than willing to assist...................
frats,
Rosco
John has put the acid on this - thanks John - (Stewart has opened up an opportunity to store information and advice such as yours within the tech section - we probably need to spend a few weeks re-formating material both new and existing and when satisfied - have it "stickied"........)
D-
I have various workshop manuals of all Holdens up to HR - The factory ones I find to be more helpful - the generics, although quite informative, fall a bit short in some areas - I would suggest to anyone to try and get a factory manual - just don't loose an arm for it.
Of course, your best source of info is either here, or within a club.............
This site is supported by many, many experienced and capable members, most of whom are more than willing to assist...................
frats,
Rosco