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Author Topic:   carb question
MINI2.3DIRTRACER
Dirt Maniac

Total posts: 115
posted August 26, 2003 04:57 AM  
hey all
quick question, my carb starting acting up sat night, the accelerator pump is sticking. every time i get on the gas i don't have my initial shot of gas(power) it also starting looping at high rpm down the straight away. i was looking at the carb (holly 350) and when the block is empty (no fuel load) i can work the linkage by hand and thet small arm that pushs up on the accelerator pump engages and dis-engages nice and smooth, but when i turn the fuel pump on and the carb block fills the small arm will not compress that accelerator pump (diapram). i tryed changing the diapram out and fliping the small spring in there over with no luck, any ideas??
thx
mini2.3

b4racing
Dirt Forum Champ
Total posts: 626
posted August 26, 2003 12:24 PM  
contact earl parker he is da man. he has a web site with his email. parkercarburetion.com I believe is it. he is very nice to call and talk to and never rushes you. Later Bobby

Earl Parker II
Dirt Full Roller

Total posts: 69
posted August 27, 2003 08:10 AM  
If I'm reading correctly when there's fuel in the bowl the accelerator pump system 'locks up' which would suggest a blockage somewhere.

The first thing I'd do is remove the pump nozzle and blow air through it to make sure nothing has lodged in either discharge hole.

Next I'd make sure that the pump check needle isn't 'frozen' to it's seat. These things usually stick after the carburetor hasn't been used for some time but it wouldn't hurt to check it anyway.

Next I'd remove the needle and blow air through the main body section of the pump passage (be sure to remove the fuel bowl and metering block first) to make sure it's clear.

Next I'd blow air through the metering block section of the pump passage to make sure it's clear.

Finally I'd remove the pump cover and diaphragm and blow air through the short passage in the fuel bowl leading from the pump cavity to the metering block.

Though it isn't directly related to your pump problem, while you're in the pump cavity you might as well take a look at the pump check valve. If you have the 'rubber umbrella' type valve make sure it's still pliable. If you have the 'check ball' type valve, give the fuel bowl a shake and see if you can hear the ball rattle in it's 'cage'. If so, fine- if not, find something soft to gently dislodge it then clean it with a Q-tip and some good carbureor cleaner. If it's got that white junk on it then clean it with a Q-tip and some Lime Away or equivalent- rinse with water and blow dry.

As for the 'looping' problem, it could be several things. I'd really need a few more details before commenting.

Let us know if the above doesn't help and we'll go to Plan B.

------------------
Earl Parker II www.parkercarburetion.com
704.482.7588

[This message has been edited by Earl Parker II (edited August 27, 2003).]

[This message has been edited by Earl Parker II (edited August 27, 2003).]

[This message has been edited by Earl Parker II (edited August 27, 2003).]

MINI2.3DIRTRACER
Dirt Maniac

Total posts: 115
posted August 27, 2003 08:34 AM  
thx much bobby / and earl
i'll give it a try and let you Know how i come out. thx again for taking time to loan me some advice.
take care
mini2.3(ERIC)

[This message has been edited by MINI2.3DIRTRACER (edited August 27, 2003).]

MINI2.3DIRTRACER
Dirt Maniac

Total posts: 115
posted August 31, 2003 02:40 PM  
well thx for the help, here's what i found to be the problem and what happen this sat;;
the metering block section of the pump passage had a lil piece of gasket blocking it, that was causing my accelrator pump to lock when it was full. so i got it cleaned out and it was working good sitting on the trailer. took it to the race and i started pole position in the heat, seemed a lil slugish coming out the turn but a 100% better then it was. i led the first two laps of 8 and then my car starting boging real bad in the turns..i was out of gas..rookie mistake.
anyway i top it off and when i go to start it to run a few laps out back before the b-main, it was real slow starting like it was getting a lil fule w/ the throtle all the way back and then it would SLOWLEY wind up to a full throtle, pulled out back and it was REAL bogush. then on the b-main it ran like crap, like it was starving for fuel the power was coming and going (mostly going) all the way around the track, i came off and put it on the trailer. well any ideas/tips. a guy at the track said it sound like the accelerator pump may have a pin hole, i don't know??
thx

Earl Parker II
Dirt Full Roller

Total posts: 69
posted September 02, 2003 07:40 AM  
Can you tell us what your fuel pressure was when all of this was going on?

------------------
Earl Parker II
www.parkercarburetion.com
704.482.7588

stewaw
Dirt Newbie

Total posts: 4
posted September 02, 2003 05:27 PM  
Any chance when you ran it out of fuel it sucked up some trash in the line like a piece of foam from the fuel cell or other foreign material and partially plugged the fuel filter?

MINI2.3DIRTRACER
Dirt Maniac

Total posts: 115
posted September 02, 2003 08:33 PM  
well i think i was running 6-8 psi, that is the size of my electric fuel pump, is there another way to measure it?? as for something pulling in my line that is a strong possability i'll have to check on that. although i thought i had a screen on the line down in the cell-but it could have a hole in it. thx for the feedback, i'll let you know what i come up with.
thx

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