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Old 09-20-2013, 04:44 PM
martyminnesma martyminnesma is offline
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a few updates from some testing.

ok so I bought a vacuum/fuel pressure gauge. when I connect the gauge in the fuel line, the needle bounces around so fast its impossible to see what the actual pressure is. is that normal? it seems to bounce between 3 and 9, sometimes falling steady for about a milisecond on 5-5.5.

when i hook the vacuum gauge up to the manifold port on the carburator, or the T fitting on the manifold behind the carb, i get a reading of 15Hg at idle. as i rev it up slowly it climbs to about 17, when i let off it jumps to 20 and then remains at 15. its idling pretty rough at the moment too. I'm thinking 15 is too low. the gauge says where the needle is sitting that my timing is too retarded, so i tried bumping it up a bit and it made no difference. and also isn't manifold vacuum supposed to disappear completely when you rev it up? not get stronger?

funny thing too, if i let the manifold remain uncovered, it almost sounded better at idle, but the engine was shaking like crazy, if i reved it up, it seemed to run better than it has before. its hard to tell without a load though, it just sounded nice for once. maybe because it was sucking extra air into the mix and leaning it out.

I swear if there is a vacuum leak it has to be in the carb itself, i've checked every gasket and hose and i can't find a single spot where its leaking, but the carb sounds loud, like a rushing, whooshing. kind of like sipping through a skinny straw really hard. but is that even possible? i need to find another spare carb to try. anyone know anyone in calgary alberta?


another few things about timing.
I replaced the weights and springs because the old ones were rusty and probably not working right, and they had a different shape that i believe allowed them to spin open more for the purposes of propane, that's why i replaced them with stock ones. but here is where i get confused....
with the vacuum disconnected, im idling at 10 degrees. when i rev it up, the weights only bring it up to about 16. when i connect the vacuum to the manifold port, it brings it up to 26. when i rev it up it climbs to a proper 36. is something weird going on here??? or is this all good?

also the HEI condenser tested fine, the coil tested as ok, but that doesnt mean much when its off and cold. but it is just an original Iron cam gear. maybe it is warn and thats why the weights are making it climb very high? i dunno? the rotor didnt seem to have a lot of play in it....

new plugs are definitely in order though, im sure they've fouled a couple. but i think my underlying problem is not the spark plugs.

I'm lost, someone please help!
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