L68 can't idle.
Thread Starter
Instructor
Joined: May 2022
Posts: 128
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From: NJ
L68 can't idle.
Any with information regarding l68 tripower idle problem.
car has been running perfect for 2 years.started this evening and alittle more smoke from exhaust than I am use to. Second car is not holding idle when I release pedal even after warming at 10k
Usually would hold idle at 6500. once started i would not have to reprime at restart. Today even after not holding idle i have to reprime with pedal
thoughts? Thanks
car has been running perfect for 2 years.started this evening and alittle more smoke from exhaust than I am use to. Second car is not holding idle when I release pedal even after warming at 10k
Usually would hold idle at 6500. once started i would not have to reprime at restart. Today even after not holding idle i have to reprime with pedal
thoughts? Thanks
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How long since it was last started and run? How fresh is the gas?
Sounds to me like the idle carb has varnish/deposit buildup from storage. You might have success with injector cleaner and fresh gas in the tank.
Sounds to me like the idle carb has varnish/deposit buildup from storage. You might have success with injector cleaner and fresh gas in the tank.
Thread Starter
Instructor
Joined: May 2022
Posts: 128
Likes: 15
From: NJ
Car has been out every weekend Been to two shows this season
after sitting at show for 4 hours started right up.. Was doing work on the house and hasn't been out for 2 weeks. It was better starting first out of winter. Maybe it's the gas I put in two weeks ago. Just odd that it's been so normal and just out of the blue fublue today and can't hold idle. Absolutely not expected.
after sitting at show for 4 hours started right up.. Was doing work on the house and hasn't been out for 2 weeks. It was better starting first out of winter. Maybe it's the gas I put in two weeks ago. Just odd that it's been so normal and just out of the blue fublue today and can't hold idle. Absolutely not expected.
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Well, it picked now to break. I had a Holley once that developed a bit of rust on the lower through bolts that hold the float bowl on. These bolts are exposed inside the float bowl. A chip of rust came free from the bolt, immediately got sucked into the lowspeed jet. Ran fine one day. Not so much the next.
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take it out and drive it, get the outboard carbs to open and flush out any sediment in those, then retry. todays gas can mess with those old carbs so easily its disappointing. They corrode very easily. IF it doesnt clear up I would take tthat center carb out and inspect the float bowl and the metering block. Could be a bunch of issues, Could also be the floats stuck as well and its not openning enough or sticking closed.
Could be condensation and your bowls collected water, water in the fuel, Go give it a hot run and get the crap out of the carbs and see
Could be condensation and your bowls collected water, water in the fuel, Go give it a hot run and get the crap out of the carbs and see
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EDIT: Before I took the carburetor apart I would confirm it's actually a fueling problem, not ignition or whatever. Take the air filter off, start the car, and see if you can smooth the idle out with blasts of ether/starting fluid.
If this trick does NOT work, I'd check for fouled plugs, and put a vacuum gauge on it to check basic engine health.
Everyone else was jumping on the carburetor float train and I failed to look B4 I lept...
Cheers.
Confirm all "old rubber" fuel lines have been replaced with modern (alcohol-proof) fuel-rated line. Melted rubber can really goop up a carb, needle & seat, jets, passageways, etc.
Asides from that sounds like you need to pull the center carb off, dis, clean, re-assemble. Rust, dirt, crap prolly blocking an idle jet / passageway . Compressed air, carb cleaner, overnight soaks, NEVER metal pokey things except as a very last resort. If you're careful you probably won't need a kit.
Float level ain't gonna suddenly change. Crud between the needle & seat far more likely cause of float sticking.
Wad of gunk or rust in the fuel bowl's the red flag. Melted non-alcohol rated fuel line will create black crud.
I install a FRESH fuel filter before re-installing ANY carburetor I've had apart. Why do the work twice?
Italian tune-ups seldom work on clogged idle jets, unfortunately.
If this trick does NOT work, I'd check for fouled plugs, and put a vacuum gauge on it to check basic engine health.
Everyone else was jumping on the carburetor float train and I failed to look B4 I lept...
Cheers.
Confirm all "old rubber" fuel lines have been replaced with modern (alcohol-proof) fuel-rated line. Melted rubber can really goop up a carb, needle & seat, jets, passageways, etc.
Asides from that sounds like you need to pull the center carb off, dis, clean, re-assemble. Rust, dirt, crap prolly blocking an idle jet / passageway . Compressed air, carb cleaner, overnight soaks, NEVER metal pokey things except as a very last resort. If you're careful you probably won't need a kit.
Float level ain't gonna suddenly change. Crud between the needle & seat far more likely cause of float sticking.
Wad of gunk or rust in the fuel bowl's the red flag. Melted non-alcohol rated fuel line will create black crud.
I install a FRESH fuel filter before re-installing ANY carburetor I've had apart. Why do the work twice?
Italian tune-ups seldom work on clogged idle jets, unfortunately.
Last edited by wadenelson; Aug 31, 2023 at 05:37 AM.
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