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Discussion Starter #1 (Edited)
my 1971 is almost sorted, the only thing im doing now is working on the fuel system, its a 250 inline six, with a monojet carb, its got a bunch of modifications to the lines to the carb, and want to make sure i am getting the right line sizes, it has 3/8 on it currently, and a filter before the carb in the middle of the engine bay (which i feel unsafe with, and will be moving) is the 3/8 line alright or does it take smaller diameter, i keep finding occasional mentions of a smaller line type
 

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Discussion Starter #3
I think it could be 5/16 inch tubing,,
which usually has a 1/2 inch wrench fitting on it..
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3/16 is purty small..
it may be a 3/8 wrench fitting..
sorry, 3/8ths not 3/16 lol was working with another cars brake line and had 3/16 on my mind
 

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Discussion Starter #6
they are pretty crimped on there with the screw on clamps, i originally thought it seemed a bit big, gonna buy a bit of 5/16 and try it out, i wonder if that larger fuel line is why it idles poorly
 

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yea 3/8 is kinda big for a Mono, 2brls are usually 5/16.. Qjets are 3/8..
line size is not usually a problem unless its too small, on a bigger motor..
maybe fuel pressure, or float height on the idle..
not sure what the monojet will handle as far as fuel pressure..
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I think
the line size is usually inside diameter on tubing..
 

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Discussion Starter #8
yea, when cold, the only way to start it is with starting fluid and then the pump will begin pushing fuel into the filter, i have thought about replacing the fuel pump itself
 

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Discussion Starter #10
choke was torn off long ago, in florida it works for the most part

haven't got around to fixing the choke issue
 

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yea, when cold, the only way to start it is with starting fluid and then the pump will begin pushing fuel into the filter, i have thought about replacing the fuel pump itself
IF you have a plastic filter on there, now would be a good time to change to a metal filter. The plastic have been known to melt, crack or break at the wrong time.
 

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my 1971 is almost sorted, the only thing im doing now is working on the fuel system, its a 250 inline six, with a monojet carb, its got a bunch of modifications to the lines to the carb, and want to make sure i am getting the right line sizes, it has 3/8 on it currently, and a filter before the carb in the middle of the engine bay (which i feel unsafe with, and will be moving) is the 3/8 line alright or does it take smaller diameter, i keep finding occasional mentions of a smaller line type
WOW! Still running the 6, my compliments and admiration to you!JP
 

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Discussion Starter #13
okay, replaced fuel lines and filter with 5/16, no fuel was coming from the fuel pump at all, so replaced it (had sat for 20 years) and put new plugs in it (hei, gapped to .35 out of the box) and it barely ran at first but eventually with some coaxing it started to run relatively well, though it was not really running right at first
 

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Discussion Starter #14

what its doing now, no clue

almost sounds like its coughing when coming off idle, also fuel stream into filter keeps getting weaker and stronger when idling
 

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Using little fuel at idle so flow changes as float calls for some. Idle sounds good to me. I can hear the alternator whining as it is charging.
Sounds ready for a test drive and really see how it is doing.
 

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Discussion Starter #17
x2 that sounds a whole lot better.. wtg JG
I don't really hear a cough, maybe its the exhaust..
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with the carb full and happy now,
maybe check the idle mixture, and timing..
is the Vacuum Advance on full manifold vacuum??
put the exhaust back on it, its just the pipe from the manifold to the bottom of the engine, but it does sound better with it on, as well as run better, now the only thing its doing is not wanting to start back up once its reached 180ish if i let it sit a minute

idle mixture is set okay i think, has 18 in pressure when idling, needle doesn't bounce at all anymore, changed the valve cover gasket due to it leaking oil onto the exhaust and smoking up a storm.

vacuum advance is on ported i believe, that was what i have read to put it on
 

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only reason I would run the vacuum advance on ported is to pass
a emissions test, then it would go back to full vacuum..
it does matter on the rest of the curve in the distributor tho,,
how much initial, total and vacuum advance there is..
stock timing specs are rather low and slow usually..
 
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