i was going to post in tech section but i think all engines and tanks are different.
Parts: gx390 carburetor and 35lph mikuni fuel pump. 1/4"inch "T" fitting and line.
So i've been working on my engine for many months trying to pinpoint why the engine either wont start ,wont stay started, would only idle if choke is off but only runs with choke open.
Well i've figured out after all these months it is a fuel problem. At first i thought it was valve lash but it isn't. i do NOT recommend going to DIYGK for advanced engine tech answers it took me since december to figure several things out on my own.
```````` Complications #Trial and Error. #Testing so you don't have to.
So i have the mikuni fuel pump now which pumps 35LPH and at first it would flood the carb so i "T" fitted a line back to the gas tank with a 1/4"fuel line. That leaned it out a lot but it could idle but with a really lean mix (engine got warm/hot fast).
````` Tried inserting a .078 Jet in the 1/4" hose but still to no luck(too much fuel). Even tried the jet where the pulse fitting area of the vacuum line is located but it doesn't even start when trying that.
````So i squeezed the inlet on top of the gas tank so it got smaller BUT still had the 1/4 inch line still on. It started and idled but if i want to "run" it i need to open the choke at the same time. So THAT worked but not good enough.
-- So maybe i am answering my own question now by saying i just need a smaller hose somehow coming from the "T" to the gas tank. But that wont work cause i need a 1/4 inch hose for the fitting. Unless there is a restrictor at autozone or a temporary DIY method with PVC glue and drill a hole in small increments.(shouldn't hurt any cause it would just degrade in very minimal increments?)
How did everyone else do it? i haven't seen a thread how to do it. Have seen video with a thread showing it has been done.
Thanks for viewing! This will not only help me but MANY others along their build. I WANT TO GET RIDING! lol
Parts: gx390 carburetor and 35lph mikuni fuel pump. 1/4"inch "T" fitting and line.
So i've been working on my engine for many months trying to pinpoint why the engine either wont start ,wont stay started, would only idle if choke is off but only runs with choke open.
Well i've figured out after all these months it is a fuel problem. At first i thought it was valve lash but it isn't. i do NOT recommend going to DIYGK for advanced engine tech answers it took me since december to figure several things out on my own.
```````` Complications #Trial and Error. #Testing so you don't have to.
So i have the mikuni fuel pump now which pumps 35LPH and at first it would flood the carb so i "T" fitted a line back to the gas tank with a 1/4"fuel line. That leaned it out a lot but it could idle but with a really lean mix (engine got warm/hot fast).
````` Tried inserting a .078 Jet in the 1/4" hose but still to no luck(too much fuel). Even tried the jet where the pulse fitting area of the vacuum line is located but it doesn't even start when trying that.
````So i squeezed the inlet on top of the gas tank so it got smaller BUT still had the 1/4 inch line still on. It started and idled but if i want to "run" it i need to open the choke at the same time. So THAT worked but not good enough.
-- So maybe i am answering my own question now by saying i just need a smaller hose somehow coming from the "T" to the gas tank. But that wont work cause i need a 1/4 inch hose for the fitting. Unless there is a restrictor at autozone or a temporary DIY method with PVC glue and drill a hole in small increments.(shouldn't hurt any cause it would just degrade in very minimal increments?)
How did everyone else do it? i haven't seen a thread how to do it. Have seen video with a thread showing it has been done.
Thanks for viewing! This will not only help me but MANY others along their build. I WANT TO GET RIDING! lol
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