Hi guys,
I realise this isn't exactly a chainsaw forum, but I guess the carbs are similar on many tools...
I bought a spares or repairs saw with an oil leak and a stripped casing thread. The seller fired it up with 4 or 5 pulls and ran it briefly.
It's a fairly old 14" Sachs saw, and the carb says "Walbro" on it (I know they make car fuel pumps...)
I took it apart to clean and check everything, up to the point of removing the carb and the plate (with reed valve) below it.
I popped one side cover off the carb, found the rubber diaphragm was well stuck in place so left it alone. I didn't mess with the mixture screws.
I put it back together and it's being a nuisance. I takes *ages* to pull the fuel up to the carb, unless I block it completely with my thumb. It then wants a little fuel dripped straight down the carb and it'll start and run for a couple of seconds. After a few goes of this it'll run properly, but will die after 10-20 seconds, despite working the throttle.
When running, bubbles appeared in the fuel pump, and sometimes the fuel tank breather would blow fuel out. Like it was pressurising the fuel line...
I pulled the carb and valve plate back off and doubled checked nothing was blocked, and replaced the gaskets (cut from paper). It's now a little better in that it doesn't froth up the tank, but bubbles still appear, but it still seems to suddenly starve and die.
2-strokes are foreign to me... With the valve plate removed and blowing into the crankcase, there was some leakage out the exhaust port.
Any suggestions greatly received - I'm really not sure where to start. I suspect it's something I've done to it!
Thanks
Anthony
I realise this isn't exactly a chainsaw forum, but I guess the carbs are similar on many tools...
I bought a spares or repairs saw with an oil leak and a stripped casing thread. The seller fired it up with 4 or 5 pulls and ran it briefly.
It's a fairly old 14" Sachs saw, and the carb says "Walbro" on it (I know they make car fuel pumps...)
I took it apart to clean and check everything, up to the point of removing the carb and the plate (with reed valve) below it.
I popped one side cover off the carb, found the rubber diaphragm was well stuck in place so left it alone. I didn't mess with the mixture screws.
I put it back together and it's being a nuisance. I takes *ages* to pull the fuel up to the carb, unless I block it completely with my thumb. It then wants a little fuel dripped straight down the carb and it'll start and run for a couple of seconds. After a few goes of this it'll run properly, but will die after 10-20 seconds, despite working the throttle.
When running, bubbles appeared in the fuel pump, and sometimes the fuel tank breather would blow fuel out. Like it was pressurising the fuel line...
I pulled the carb and valve plate back off and doubled checked nothing was blocked, and replaced the gaskets (cut from paper). It's now a little better in that it doesn't froth up the tank, but bubbles still appear, but it still seems to suddenly starve and die.
2-strokes are foreign to me... With the valve plate removed and blowing into the crankcase, there was some leakage out the exhaust port.
Any suggestions greatly received - I'm really not sure where to start. I suspect it's something I've done to it!
Thanks
Anthony