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It Starts! But doesnt run...

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blkcorvair

Jedi Knight
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Well I finished the complete wiring harness and dash yesterday. Only one wire that I questionably don't know how I hooked it up wrong but none the less, all the bells and whistles are working. So I put my elec. fuel pump in tonight fabricated some cables and brackets for the new su carb and topped everything off. And whala! It started. Turns out I was flooding it because I had the overflow and feed hos crossed, but after working that out I doens't stay running. Pops stall, stumbles stalls. Fuel is definatally getting to the carb. But I must say I have not touched an SU since I worked on my Datsun when I was 15. So it is a bit new too me. Dont know if I may be doing some thing wrong. Maybe fuel pressure, or that adjustment for the needle seat. (Which I have set at two turns out.) I assumed plu the balance tube (From the original 2 carb setup and I rebuilt the carb.) The timing ought to be fine at least to get it running as it ran with the weber before I yanked the engine. Never fooled with that. Any suggestions. Here's some pics!

IMG_2049.jpg


IMG_2047.jpg
 
What type ignition are you running? Points? Electronic? Also, what do the plugs look like after the start-up? Wet? Dry? Stock electric pump or adjustable aftermarket? Looking good! /bcforum/images/%%GRAEMLIN_URL%%/yesnod.gif
 
Yeah...kind sounds like fouled plugs.
Easiest thing is just to put some fresh ones in.

Make sure that you don't have the fuel pressure too high (1.5 lbs is *plenty* for just starting and running at first).

On the other end, be sure that there is fuel in the carb float bowl and that your float-bowl needle is not stuck closed (or open). Two turns down on the main jet (under the vacuum piston) is about right.

Plug wires should be 1-3-4-2
Right?
 
1-3-4-2 <u>Counterclockwise</u>, and check the timing. I know it ran before but alot has happened since then
 
electronic ign. definatally sounds like a fuel problem. like starving. Although fouled plugs could be a possibility. I also did cut a lot of stanless line, so I wouldnt be suprised if some rubber shards found there way into the bowl. Fuelk pressure set a 3 lbs
 
only seconds. If that. Lots of popping than nothing. When it starts for 3-5 seconds sounds smooth and than dies out like it ran Out of gas. I just took the bowl off (Full of rubber fregmnets just as I suspected.) I also had a grose jt in there. Dont know what anyones experiance is with them so I swapped the original su needle valve back in. Gonna go fire it up now and check the plugs.
 
Be sure to blow backwards from the jet to the bowl with compressed air to clear the line from the bowl to the jet.
 
Sounds like you found the problem. The fix may be easy or may be a PITA. Little engines do not run on rubber, hehe.
 
ANY dirt/sediment/residue in the float bowls is a recipe for trouble that requires a good, thorough cleansing of the carbs, at least a good blow-out of the bowl, needles and seat and jets!! /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
 
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