I have a Craftsman 25cc leaf blower that I have been struggling with. I have taken a lot of advice here but still can not get it to start. It has spark, the carb 'looks' clean (no gunk), I can see gas pass through the tubes from the tank to the engine, and the oil/gas mixture is correct. The only thing I don't know is the compression nor do I know how to check that.
Any suggestions for these symptoms? Thanks!

Check your cylinder head bolts, should just be two of them. If they are loose you will not have the compression you need. Also, check the exhaust port, if it is clogged, or clogging it will not run at all sometimes, or will not seem to take throttle. And to check compression properly, you would need to use a compression tester. You can purchase an inexpensive compression tester, or you can spend a lot more than what the weedeater cost new for a compression tester. I would start with cleaning the carb. Dumping the fuel, add a new fuel filter if I had any doubt. Then start over with fresh fuel mixture.

It is doubtful that the compression is the problem since that would go bad over a long period. 9 out of 10 times it is a bad carb jet on these small engines. Try to remove the bowl and needle valve. Flust you lines and the jet with fresh fuel and reassemble.

Is it a 2 cycle engine? Are you mixing oil with the gas if it is? Did it overheat? Check the air cleaner.

Prime about 5x. Lever to choke. Lock at full throttle. Kill switch off. Pull until it sputters or starts. Take choke off.

I blew up 2 echo ES-230 leaf blowers because of the type of leaves I was picking up. The mulched leaves did a number on the external cooling fins. Echo replaced it twice. On the third time hey offered me my money back or to downgrade continuing the warranty.

I bought a Stihl and it's been working fine. There are things I like and dislike about both. Echo admits the design flaw on the 230

Wow, kiss, I would have suspected I was just having a bad day, ha ha. I agree with you though, I too prefer Stihl over any other. I have owned Stihl products for years, and other than routine maintenance and putting the fuel mixture in them, I do nothing except KNOW that when my Stihl is needed, it is waiting on me, because my Stihl's have always been and are always READY to WORK. In case you can not tell I love Stihl's products.

Also, on the Stihl blower you will find 4 head bolts, instead of like most of the others which have cut down to only 2 head bolts.

Stihl is not a "friendly" company. Their service manuals are pitiful compared to Echo's providing you can get a hold of one.

I am annoyed that I need a screwdriver to open the intake grill and there is no kill switch there. I'm also annoyed that they don't make it easy to determine what inserts where. The black tabs (square vs Round) are difficult to see when the unit is on the ground and it's darkish outside. They need racing stripes to know when the tabs are lined up properly for removal and twisted properly after insertion. The bag has a zipper that's too small to grab. Just little annoying things.

I wish they would all have over temperature cut-outs and it would be really neat if they had an LED that blinked if everything was ago while trying to start it.

Well kiss, you can't have your cake and eat it too, but for me I get CAKE AND ICE CREAM with my Stihls.

Thanks for the responses. A bolt was loose previously on the cylinder head but it ran since than, just not well. Now I can not even get it running.
Embarrassingly I'm not sure what part of the carb is the bowl and needle. The unit is only about an inch square with the choke lever on one side and the throttle on the other. I was planning on soaking the piece in cleaner and flossing out any cavity I could see and try again. Beyond that I am at a loss.

There will not be a bowl, so to speak, but you will find a needle valve inside, before soaking remove and gaskets and diaphrams, carb cleaner solution will ruin them. Also use safety glasses, and put out a large piece of white cloth to disassemble and clean the carb on. You can get rebuild kits for some, not all carbs. If you have a walbro, or zama carb, most of them have kits available. Good luck, you can do it.

Did you try pulling the cord?

I have a similar craftsman unit, and the prime bulb won't pump fuel into the carb. I got it started with starter spray and then it ran but slowly, and I had to constantly squeeze and release the throttle. Like it doesn't want to run full speed.
The two hoses are connected to the bulb/carb (brass nipples). Any ideas?
Thanks
Doug

Fuel, spark and it still doesn't run? My Craftsman blower was flawless for two years then one day it would not run. After disassembling it, the most visible and least mentioned remedy was compression. The single piston ring was carbon coated and actually fused to the ring groove. Removing, cleaning and replacing the piston ring was the correct repair.

I always tend to make repairs more complicated than needed. Compression is a key component for two stoke engines. When cold, compression would normally be higher and when warmed up much less. This explains why these things are so sensitive.

It runs like new, should be good for another two years. Hope this helps.