Moparchat - Home of MOPAR enthusiasts worldwide!



Go Back   Moparchat - Home of MOPAR enthusiasts worldwide! > Technical Forums > Performance Talk

Click here to search for Mopar cars and parts for sale.


Reply
 
Thread Tools Display Modes
  #1  
Old 09-27-2002, 02:11 PM
73_RoadRunner's Avatar
73_RoadRunner 73_RoadRunner is offline
Registered User
 
Join Date: Mar 2002
Location: Monroe, Michigan
Age: 41
Posts: 475
Angry how to set floats on 750 dubble pumper?

i took my carb all apart and i was messing with the float adjust ment and i want klnow how you get them set right for my car its on a 440 with dominator intake i really should have left them alone but i was cleaning it up
Reply With Quote
  #2  
Old 09-27-2002, 04:04 PM
66 Dartman's Avatar
66 Dartman 66 Dartman is offline
Inactive User
 
Join Date: Sep 2002
Location: Linwood, PA
Age: 54
Posts: 244
Default

Take out the sight plug on the side of the bowl and turn the adjuster until gas just starts to run out of the hole where the plug was. The car has to be running to do it that way. Otherwise you'll probably have to look up the float drop measurment and set it off the car.
Reply With Quote
  #3  
Old 09-27-2002, 04:59 PM
73_RoadRunner's Avatar
73_RoadRunner 73_RoadRunner is offline
Registered User
 
Join Date: Mar 2002
Location: Monroe, Michigan
Age: 41
Posts: 475
carb adjusting

so you do the same for the front and back? if gas runs out of the hole to i screw the adjuster in or out ? so just make it where it doesnt come out the plug hole ? what about the air adjustments?



thanks for the help do you think the 6.5 power valve is the right one for my car 440 s speed?
Reply With Quote
  #4  
Old 09-27-2002, 05:24 PM
66 Dartman's Avatar
66 Dartman 66 Dartman is offline
Inactive User
 
Join Date: Sep 2002
Location: Linwood, PA
Age: 54
Posts: 244
Default

Ok, It's been a while since I've messed with a holley but I'll tell you what I remember.

You'll have to mess with the adjuster on the float to see which way to turn it, I don't remember off the top of my head. But, yes, set them both the same, front and back. until the fuel just reaches the opening of the plug hole.

For the air adjustment, it is best to use a vacuum gauge if you have one. Hook it to a vacuum port on the manifold. You want manifold vacuum, not a ported vacuum source. Adjust the screws all the way in, (don't seat them too hard though or you'll mess them up) just till they hit bottom. Back them both out like 2 turns. Then one at a time, adjust them for highest manifold vacuum reading. Turn them about a quarter of a turn and wait for 5 seconds or so for any reading changes, keep doing that, in and out, till you find the highest reading. If you can turn them all the way back down so they bottom out, you have a bad power valve or some kind of internal vacuum leak.

If you don't have a gauge, you can do it by ear. Start with the screwws two turns out from bottom. Adjust them slowly again about a half turn at a time. Listen for changes in the idle speed of the engine. Adjust it down till the idle starts to drop, then back the screw off a half a turn from there. Do it for both sides.

As for the power valve. It is best to get a vacuum gauge from someone if you don't have one or buy one, you'll need it....
Measure the vacuum at a manifold vacuum port and subtract 2 inches of vacuum from that reading. That is the power valve to start tuning with. If your engine is holding 8.5 inches of vacuum at idle, start with a 6.5 power valve.

It has been a long time, like I said, since I messed with a Holley. But to the best of my knowledge, that is the way to get things set up. Maybe some of the other fine gents in the forum can let me know if I missed anything or mis-stated anything.
Reply With Quote
  #5  
Old 09-27-2002, 05:58 PM
71383bee's Avatar
71383bee 71383bee is offline
Inactive User
 
Join Date: Mar 2001
Location: Milwaukee, WI
Age: 48
Posts: 654
Post

Roadrunner,

66dart has got you on the right path. Clockwise lowers the floats Counterclockwise raises the floats. For the power valve go to the sticky at the top of the forum from cuda66273 titled power valve tuning. That is the best guide I can think of.
Reply With Quote
  #6  
Old 09-27-2002, 10:25 PM
pishta's Avatar
pishta pishta is offline
Senior Member
 
Join Date: Aug 1999
Location: Tustin, CA
Age: 55
Posts: 3,987
Default

another old trick is to invert the removed bowls and let the float rest on the needle. you should be able to put a pencil between the float and the bowl. Itll get you close. I would recommend doing the float adjustment with an I.V. bag full of fuel or some other rig to let the gas into the carb with the motor not running, it is a safer operation, Electric fuel pump would be best. remember you are turning the hex, not the screw. And if you do do it while the car is running, prepare for a squirt of fuel out the adjuster if you crack it too much. This was my least favorite thing to do on a running motor. Demons have HUGE sight glasses that dont fog with reference lines on them. Nice job, Barry!
Reply With Quote
  #7  
Old 09-27-2002, 11:59 PM
66 Dartman's Avatar
66 Dartman 66 Dartman is offline
Inactive User
 
Join Date: Sep 2002
Location: Linwood, PA
Age: 54
Posts: 244
Default

I guess I should have looked at those stickies first. Maybe the moderator can sticky mine titled "Pennsylvania Redneck carb tuning"
Reply With Quote
  #8  
Old 09-28-2002, 01:32 PM
dhochsprung dhochsprung is offline
Registered User
 
Join Date: Jan 2000
Location: Houston, TX
Posts: 66
Default

The website www.bob2000.com/carb.htm has a good explanation on setting up a Holley carb. I think you will find it useful.
Reply With Quote
  #9  
Old 09-28-2002, 05:29 PM
73_RoadRunner's Avatar
73_RoadRunner 73_RoadRunner is offline
Registered User
 
Join Date: Mar 2002
Location: Monroe, Michigan
Age: 41
Posts: 475
Question adjusting carb

so when i adjust the floats to make the gas level drop turn the adjuster clockwise ? gas squirts out the adjuster when i adjust it is that sapose to? when adjusting the air screws should the regular idle screw that opens the butterflys should that be screwd to idle it up till i get the air screws adjusted then lower it for the right rpm or should it be barly srewed in for lower rpm then adjust it? and for the air screws do i turn the screw quarter turn then go to the other side and turn it the exact same or do i just adjust one side till perfict then go to the other side and adjust that side?

when setting the floats the car has to be running while you adjust it? cause the car shakes wouldnt that make the gas spill out or do i let it leak out and adjust it while its leaking out and adjust the float till i just stops coming out wile running?

just making sure i been adjusting it i got it close but i cant get the rpms down enough it might be that the float levels are to high?

thanks
Reply With Quote
  #10  
Old 09-28-2002, 06:53 PM
73_RoadRunner's Avatar
73_RoadRunner 73_RoadRunner is offline
Registered User
 
Join Date: Mar 2002
Location: Monroe, Michigan
Age: 41
Posts: 475
Unhappy setting engine idle

i got the carb pretty good the gas is at the level of the plugs put the car is idling too high it wants to run around 1,000 rpm and i have the idle linkage screw backed out all the way is it the air scews messed up or floats? how do i fix it
Reply With Quote
  #11  
Old 09-29-2002, 05:07 PM
pishta's Avatar
pishta pishta is offline
Senior Member
 
Join Date: Aug 1999
Location: Tustin, CA
Age: 55
Posts: 3,987
Default

if the idle set screw is all the way out (like not touching the linkage) and you are still at 1000, you got a vacuum leak, or the secondary throttle screw located UNDER the carb, that touches the secondary butterflys, is keeping them open? Do the idle mix screws do anything, like can you close them (tighten them all the way) and not stall? Vacuum leak! Start looking for one with a squirt bottle and soapy water, soak the runners where they hit the heads, and around the base of the carb. Plug all vacuum hoses at the source with caps, maybe you got a cracked vacuum line somewhere. Check timing again. Remove your pedal linkage, maybe you got some stress on the throttle lever. Your base can be warped, not uncommon. After everything checks out, return all screws to base. 2 turns out on each idle mix screw, one turn in on the idle speed screw, and just touching on the secondary throttle stop screw (under carb) The fuel will squirt out, you are doing it right.
Reply With Quote
  #12  
Old 09-29-2002, 08:48 PM
73_RoadRunner's Avatar
73_RoadRunner 73_RoadRunner is offline
Registered User
 
Join Date: Mar 2002
Location: Monroe, Michigan
Age: 41
Posts: 475
Default air screws

Quote:
Originally posted by pishta
if the idle set screw is all the way out (like not touching the linkage) and you are still at 1000, you got a vacuum leak, or the secondary throttle screw located UNDER the carb, that touches the secondary butterflys, is keeping them open? Do the idle mix screws do anything, like can you close them (tighten them all the way) and not stall? Vacuum leak! Start looking for one with a squirt bottle and soapy water, soak the runners where they hit the heads, and around the base of the carb. Plug all vacuum hoses at the source with caps, maybe you got a cracked vacuum line somewhere. Check timing again. Remove your pedal linkage, maybe you got some stress on the throttle lever. Your base can be warped, not uncommon. After everything checks out, return all screws to base. 2 turns out on each idle mix screw, one turn in on the idle speed screw, and just touching on the secondary throttle stop screw (under carb) The fuel will squirt out, you are doing it right.
if i screw the air screws in the car wants to shut off should the loats not leak any gas at all while running out the plugs? the carb worked good i just took it apart and put it back togeather no this crap i will try that secondary screw eventho i never moved it and it was idling fine before thanks for the help
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Holley Double Pumper kennymopar Performance Talk 11 11-24-2009 05:26 AM
need help to find good baseline jess for my holley 650 spreadbore dubble pumper moparjoe3604 Performance Talk 5 03-27-2007 07:52 PM
How much would a double pumper help my 60? party340 Performance Talk 10 03-15-2006 03:33 AM
double pumper Pootus Performance Talk 3 07-28-2002 04:56 PM
a set of pumper or fnowflake wheels Mahtipsey Front Wheel Drive - Parts Wanted 1 04-24-2002 10:33 AM




All times are GMT -4. The time now is 04:51 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
. . . . .