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drowning engine

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hvymetalalchmst

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heres the rundown;

my engine runs. i can't tune it as it doesn't run long enough to get warm (get to that later)
I've rebuilt it, replaced the bearings and inspected all parts. should be alright.
stripped and cleaned carby. should be alright
i have some 2 week old fuel (but the climate has been cool and wet)

in Australia, this should be summer, and hot. we should be panting on the porch like dogs, but these last two, three days, we have had over 200mm rain (about 9in) so i couldn't run it. seeing as it is starting to stop raining, still cloudy and forecasted to rain some more today, i can't run it still.

when i did, the engine ran nice, though randomly, out of nowhere, sounded like someone ripped off the carby and gushed a gal of fuel down it. the engine just stopped, lost all power and sat there gasping for air. if i WOT it, it just makes a slightly higher pitch, but same drowning sound. if i leave it, it stays for about a good 10, 15 secs, then dies. i don't get why the thing suddenly loads up. for the few min before it does that, it runs fine.

if i start it up again, it just repeats itself.

when i get the chance, i will try to pinch the fuel line and WOT it, to check if its the fuel or whatever. my brother says that he tipped it 45deg towards the left side (its mounted on the rear left of the car), it took a while to clear up and run normal again. the exhaust port is at the rear of the engine (go figure).

can anyone diagnose the problem? i am completely lost.
 
As long as you're getting a descent idle, don't touch the LSN yet.
When you do the pinch test, have it at running temperature. Just pinch the fuel line near the carb. Don't give it any throttle.

If the engine shuts off in MORE than 4 seconds, lean the HSN, get it running and test it. Then do the pinch test again.
If it cuts out in a second or 2, you're way too lean and will need to richen the HSN. Don't go more than 1/8 turn at a time between tests.
When you've done that, get back to us here.
 
lol i can't get it to run to running temp. its far from warm when it starts drowning itself.

It idles fine cold.

i know how to tune, and this does not look like a tuning problem.

hsn is about 3 turns, slightly rich (i know its not too rich, from before.)
lsn is about 2.5 turns (its correct for this engine. I've tried.)
dont worry about these needle settings. it is an old 5year old engine. its not too rich, though it may seem like it.
 
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After it stalls out, is your exhaust pipe full of fuel? Is it truly flooding, or just sounds like it is? Do you have an adequate length of fuel line from the tank to the carb? Are you running a hot enough glowplug for the fuel your using?
Just a few things to look at..
 
After it stalls out, is your exhaust pipe full of fuel? Is it truly flooding, or just sounds like it is? Do you have an adequate length of fuel line from the tank to the carb? Are you running a hot enough glowplug for the fuel your using?
Just a few things to look at..

the exhaust is not FULL of fuel, but has more than usual. i think it sounds as bad as it is - just barely enough the let it live a few more seconds. the length of fuel line is about 6in, but has been adequate for all the time i have ran it. the glowplug is fine, its an OS#8.

i must emphasize it works perfectly for the few moments before hand. there is no sign of this problem then BAM! and it happens instantaneously.
 
note to self; when diagnosing problems, experience them first hand, not by word from inexperienced people (namely my brothers)

the problem was... here it is...

the lsn was waaaaaay too rich! (sorry rolex for doubting you) how i figured out? well, after thorough questioning, they finally told me "i think it only happened after half-throttle". one of those very, very disappointed looks washed over my face. arrrrrrrrrrghhhhhhhhhhhh!

at least we learn from our mistakes...
 
You seem to be a pretty bright guy. Obviously you've made WAAAAAAY more mistakes than most of us have.

touché... i have made more mistakes than most. you also seem to know that by fact, you also seem rather bright, and from that basis, i assume we may have something in common, huh?
 
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