monte70car Posted September 19, 2011 Share Posted September 19, 2011 So I put my last Holley I had on the car back on yesterday so I could try and make a local show, did a few test runs last night after switching fuel pumps. Took the car for a test drive up a hill and there was no power going up the hill popping out the exhaust. Come back home do a little tweaking to the carb. then when getting back on the throttle after coming off a hill it just bog. I took the carb back off this morning and went through it as its been sitting on the shelf since May, did not see any trash in the fuel bowl did change the power valve from a 6.5 to a 7.5 as the cam makes 15" of vacuum, did not change the jets as they are 68 put a sifter spring in the secondary's brown for the plain that was in it mixture screws are turned out 2 1/4 turns fuel psi is 7#. I'm just lost on this bog as it wasn't there last year. While I was going through the carb I set the clearance between the pump arm and the pumper to .015 thinking that might be the problem, as for the pump cam it looks to be yellow in color. Quote Link to comment Share on other sites More sharing options...
72 LS5 Posted September 19, 2011 Share Posted September 19, 2011 Specifically which carb is this? Did you blow out all the air-bleeds with carb cleaner or compressed air? I always remove the air/fuel screws and blow out those holes as well. If it worked fine in May, and doesn't now, sounds like something is plugged or clogged, like the air bleeds. How is the idle? 2 1/4 turns seems a little on the rich side. Timing and spark are good? Quote Link to comment Share on other sites More sharing options...
monte70car Posted September 19, 2011 Author Share Posted September 19, 2011 I took the carb completely apart yesterday morning/afternoon could not find anything in the fuel bowls that would be an issue. I did change the power valve out for a 7.5 vs. a 5.5. as far as the spark plugs 1,3,5,2,4,6 are all white with 7,8 being carbon foul. It sit there and idle 1,000 in park and when its pulled down into overdrive the rpm's drop to 900 there is no signs of it being rich at idle(been there years ago where the plugs would be fuel soaked). The carb sit on top of one of our cabinets with a cover over top of it and everything was blown out. It's a 3310 750 vacuum secondary with a metering plate on the secondary side. I just checked timing and have a base of 14° and a max vacuum of 14", reving the motor in park there doesn't seen to be any signs of popping or a bog like before. Quote Link to comment Share on other sites More sharing options...
72 LS5 Posted September 20, 2011 Share Posted September 20, 2011 reving the motor in park there doesn't seen to be any signs of popping or a bog like before. So is it fixed? Quote Link to comment Share on other sites More sharing options...
monte70car Posted September 20, 2011 Author Share Posted September 20, 2011 Hopefully will get a chance to find out this afternoon. Quote Link to comment Share on other sites More sharing options...
John Burns Posted October 8, 2011 Share Posted October 8, 2011 Did you ever fix this? I saw your other post about the fuel pressure gauge- this sounds like the what happened to my friend's fuel system. The fuel filter was clogged. You couldn't tell anything from sitting at idle revving the motor, but it was a mess to drive. Quote Link to comment Share on other sites More sharing options...
monte70car Posted October 8, 2011 Author Share Posted October 8, 2011 No haven't had the time to do a test drive since the carb was put back together due to the rain we've had in the past two weeks, plus we have been busy working on the Nomad. I have to see my list of shows to see if there is any close by if not the fuel injection will be going back on once my show season is over. Quote Link to comment Share on other sites More sharing options...
TrunkMatt Posted December 5, 2011 Share Posted December 5, 2011 If you ease into the accelerator vs mashing the pedal from a stop what is the behavior?? Is there a bog when you mash the pedal? I had a similar issue, and had to up my Holley's pump shot nozzle to a .35 Accelerator Nozzle (from .31) , and run the Green Pump Cam instead of the pink... Quote Link to comment Share on other sites More sharing options...
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