Stihl 028 av just will not start

[Stihl Sucks wont start]

Stihl 028 AV will not start after a basic tune-up. Replaced carb, gas, gas line, gas filter, electronic ignition, piston, piston rings, spark plug. PSI was 90; now it's 125. It started once, I tried to adjust the carb, but it died. Now I can't get anything. Do you have any ideas about what I could do now? To me, it sounds like a fuel problem of gas not reaching the piston intake. I've replaced the carb 2 times as they are cheap, but they make no difference. The gas is new, the gas line has no leak, the gas filter is new so I'm assuming the problem is between the carb and the piston. I've rebuilt 2 carbs, but they make no difference, just like when they were new and installed. This is driving me nuts. The rubber thing between the carb and piston is fine, no leak. I bought this saw 30 years ago, and it's in good shape. Maybe used it 3 or 4 times since I bought it. Mainly, it's been a dust collector. replaced the piston and rings and housing because there was bad wear on the exhaust side of the piston, rings worn down, scratching on the piston.

 

[cutandchat]

See if the impulse line and port are blocked or broken. If they are, the carb can't pump fuel. Also, check the flywheel key to be sure it's not sheared off, because the timing could be wrong even if you're getting a spark.

 

[CaptTurbo]

Stihl 028 AV will not start after a basic tune-up. Replaced carb, gas, gas line, gas filter, electronic ignition, piston, piston rings, spark plug. PSI was 90; now it's 125. It started once, I tried to adjust the carb, but it died. Now I can't get anything. Do you have any ideas about what I could do now? To me, it sounds like a fuel problem of gas not reaching the piston intake. I've replaced the carb 2 times as they are cheap, but they make no difference. The gas is new, the gas line has no leak, the gas filter is new so I'm assuming the problem is between the carb and the piston. I've rebuilt 2 carbs, but they make no difference, just like when they were new and installed. This is driving me nuts. The rubber thing between the carb and piston is fine, no leak. I bought this saw 30 years ago, and it's in good shape. Maybe used it 3 or 4 times since I bought it. Mainly, it's been a dust collector. replaced the piston and rings and housing because there was bad wear on the exhaust side of the piston, rings worn down, scratching on the piston.

Have you made sure that you have spark? Did you inspect the coil and kill switch for shorts?

 

[Stihl Sucks wont start]

yes there is spark, i replaced the coil just to make sure

 

[STIHLTECH]

Does it start with a little fuel down the intake? You did a lot of good work so far. You need to do a vacuum and pressure test to verify.
Check that pulse hose as suggested. Get a good look at the intake boot. No leaks and seated properly.
Another couple things that are missed on an 028- choke flap closing and a fast idle on choke AND first notch down. I have had a very hard start or no start without a fast idle.

 

[Stihl Sucks wont start]

I did a pressure test it was 90 but now is 125 since the piston and rings were replaced. If I take out the spark plug and squirt some fuel in, replace the spark plug and pull, there is no response. I thought that unusual, but when I checked for spark it was ok I checked the pulse hose b4 it was good, the intake boot is good, and also seated properly. When it was starting on choke, it had a fast idle, then I put the switch in the middle, and it idled down, but stalled. Ive read something and watched videos of marriedtochainsaws on the entire strip down and rebuild of a 028 av, very informative but still cant find what might be wrong, oh and thanks very much for trying to help me, i really appreciate it

 

[CaptTurbo]

I did a pressure test it was 90 but now is 125 since the piston and rings were replaced. If I take out the spark plug and squirt some fuel in, replace the spark plug and pull, there is no response. I thought that unusual, but when I checked for spark it was ok I checked the pulse hose b4 it was good, the intake boot is good, and also seated properly. When it was starting on choke, it had a fast idle, then I put the switch in the middle, and it idled down, but stalled. Ive read something and watched videos of marriedtochainsaws on the entire strip down and rebuild of a 028 av, very informative but still cant find what might be wrong, oh and thanks very much for trying to help me, i really appreciate it

It seems to me that if there is spark, air, and fuel the timing must very very far off?

 

[Stihl Sucks wont start]

I tore the saw down once more and checked that my flywheel was in good working order; everything was fine. poked around a bunch and checked for spark, there was some, but not very bright. so i replaced the coil with one i had bought b4. The spark was much stronger, so I left it in. I put on the choke and pulled the cord; 4th time, the engine started. I adjusted the hi and lo, and it idled and revved up well. So to my complete surprise, it is now working. and it only costs $100 in parts. I will be playing with it tomorrow. I guess the moral here is to check, check and re-check. Thank you to everyone who responded.

 

[CaptTurbo]

I tore the saw down once more and checked that my flywheel was in good working order; everything was fine. poked around a bunch and checked for spark, there was some, but not very bright. so i replaced the coil with one i had bought b4. The spark was much stronger, so I left it in. I put on the choke and pulled the cord; 4th time, the engine started. I adjusted the hi and lo, and it idled and revved up well. So to my complete surprise, it is now working. and it only costs $100 in parts. I will be playing with it tomorrow. I guess the moral here is to check, check and re-check. Thank you to everyone who responded.

Hallelujah!