Ryobi line trimmer plt3043a starts idles but dies when i attempt to increase speed

Implies carburetor low speed fuel circuit lean. Increase low speed fuel/air.

Initial setting is 1 1/2 turns. Increase idle speed enough to keep the engine runnning so a proper adjustment of the low speed air/fuel mix can be completed.

Basic rules; Always adjust low speed a/f first, then open throttle and adjust high speed a/f. Any low speed adjustment must be followed with a high speed adjust. Error on the rich side for high speed. Allow engine to reach operating temperature for final adjustment.

Other potentual issues, fuel quality, fouled carburetor, old impulse diaphragm (carb), carb to engine intake gasket leak, crankcase leak.

Removing tines makes it easier (safer).

this sounds strangely like the high speed jet/pathway in the carb is clogged up with something ,

the best way to fix it is dissasmbly and cleaning of carb in solvent , but ive also had some limited sucess in past of using car fuel cleaner (says on bottle "cleans as you drive") too

check the fuel filter in the tank, check that the cap is free of debris in the vent hole, as its idling, and you try and increase the rpms' adjust the high run screw out a 1/8 turn at a time until it achieves the desired speed, Clean the air filter

Check the air filter isn't dirty.
If the machine runs ok on high speed but cuts out while idling, the idle speed may be too low. There is usually an adustment screw for increasing the speed.
If the fuel line is a flexible type which moves around inside the tank, check it is able to move freely because if you are cutting at awkward angles, the end of the line can end end up above the surface of the fuel, **** in air and airlock the line. You can eliminate this as the problem by fully filling the tank.
Check whether there is a one way check valve on the tank. This vents air into the tank as the fuel leaves for the carburettor. Sometimes particles of dirt can get stuck in this.

The theory is much the same on all chainsaw carbs, start and warm the machine up, increase the idle speed with the idle screw if it will not tick over, start to turn the L screw in, the revs will increase as the mixture leans off, it will reach a point where it is too lean and start to die, at that point turn the screw out 1/4 turn, check it revs up clean, if not turn screw out bit at a time until it does, now set the idle speed with the idle screw. Before attempting this make sure the fuel filter is clean, and also the air filter.

Check at the exhaust port. Clean out any carbon buildup there. Believe me, it makes a big difference. Hope this helped and best wishes.

you need to adjust the high speed needle turn it out in 1/4 increments as you throttle it, low speed may have to come out alittle but do high speed first. I had to answer this as I use to have a pastor john in sturgeon bay, miss him alot.

Your carburetor needs cleaned. Disassemble carb. and spray with carb. cleaner. Make sure that the small screen is free of debris. Use a Den Tek Brush,
(http://www.dentek.com/shop.php?target=products&product_id=7), to clean the small portals in the carb. Reassemble and start. If this doesn't work for you then you will have to buy a carb. kit and replace all appropriate parts. If you need further assistance, just let me know.

Jim

I have a rayobi PBV30A petrol trimmer and it keeps dying once you increase the throttle speed runs on idle.

Hi
Please try these suggestions if youve not done so already:

1. Clean the air filter
2. Check fuel primmer bubble (if it has one pressurizes)
3. Spark at plug, when pulling cord (When they degrade, some plugs can fire itermittently - check also with a continuity meter) BUY a new plug
4. Fuel in present in the combustion chamber (use a torch to see inside plug hole if the if the piston head looks wet from petrol) also the smell will definately be strong
5. You ay need to adjust the carb idling screw to increase idling speed when engine has warmed up.

These things I tried after investigation & worked for me, unit starts up a treat. Hope thisa helps

Aky1967