69 fuel system
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Cruising
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69 fuel system
69 350 holley 6210 - fuel siphoning through secondary venturies at idle and up to 30seconds after shutdown. Evap canister removed, lines plugged, fuel cap off.
Last edited by par4jets; Oct 28, 2009 at 01:14 PM.
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There are only a few things that will cause the fuel to overflow....
Bad float
Bad needle and/or seat
dirt or other debris blocking the needle from closing in the seat
improper float setting
heat soak
Since you're working with a reman and you have had this same problem with other carbs, I would start looking at the heat.
Bad float
Bad needle and/or seat
dirt or other debris blocking the needle from closing in the seat
improper float setting
heat soak
Since you're working with a reman and you have had this same problem with other carbs, I would start looking at the heat.
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Cruising
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can you please offer some clarification on heat soak & how it would affect the secondary outlet circuit? Problem does indeed arise after engine reaches normal operating temp. (Ice packed secondary bowl, no change) The needle, seat & float all seem to be just fine. This is an out of the box reman.
Haven't inlet fuel pressure - running factory mech. pump - assume 5-7psi.
Haven't inlet fuel pressure - running factory mech. pump - assume 5-7psi.
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From: central FL, near the beach.
my 6210's like a lower float level, i can't explain why.
.
i'd swap the 2 needle/seat/floats, as a test, if a lower float doesn't cure it.
.
once i had flooding and when i checked pressure it was 18 psi
changed fuel pump.
.
i'd swap the 2 needle/seat/floats, as a test, if a lower float doesn't cure it.
.
once i had flooding and when i checked pressure it was 18 psi
changed fuel pump.
Thread Starter
Cruising
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I'll check the inlet pressure, though I don't quite see how high fuel pressure would affect the secondary circuit while the idle circuit is fine.
The secondary float level is already very low - maybe 40 degrees south of parallel to inverted bowl.
Really curious about nitronicks' heat soak comment though. Holley suggested that fuel may be boilng in the bowl, causing needle to unseat. But again, why is primary side fine?
The secondary float level is already very low - maybe 40 degrees south of parallel to inverted bowl.
Really curious about nitronicks' heat soak comment though. Holley suggested that fuel may be boilng in the bowl, causing needle to unseat. But again, why is primary side fine?
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From: central FL, near the beach.
u should be using 108-21 gasket to prevent heat soak.
.
i'm curious u think u have heat, wth ice on the bowl
.
u have had this w/several carbs? sounds like high psi, or the 108-21 gasket is missing.
.
i'm curious u think u have heat, wth ice on the bowl
.
u have had this w/several carbs? sounds like high psi, or the 108-21 gasket is missing.
Last edited by Matt Gruber; Oct 28, 2009 at 04:28 PM.
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you didnt specify which 350 you have. My 350/350 came with a return line on the fuel filter. Is this missing on your car? It recirculates fuel to the tank which would cool it and relieve a fuel pressure that is too high at idle or bleed the pressure off when the engine is turned off.
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Yep, using the stainless plate on top of the thick gasket as recommended by holley.
I'm curious too Matt - sounds like a reach - but since two sources have raised the issue I'd really like some more specific info.
Will check the inlet pressure this afternoon. Thanks.
I'm curious too Matt - sounds like a reach - but since two sources have raised the issue I'd really like some more specific info.
Will check the inlet pressure this afternoon. Thanks.
Thread Starter
Cruising
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you didnt specify which 350 you have. My 350/350 came with a return line on the fuel filter. Is this missing on your car? It recirculates fuel to the tank which would cool it and relieve a fuel pressure that is too high at idle or bleed the pressure off when the engine is turned off.
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this is a link to the correct filter showing the return fitting
http://www.ecklers.com/product.asp?p...3&dept_id=1272
http://www.ecklers.com/product.asp?p...3&dept_id=1272