redmax trimmer problems

[kels]

here is the deal, I have been running all redmax equipment all along, I have had no problems with any of it, until now. Both of my trimmers (BCZ2500S) are now having problems cranking, they act as if they are flooded all the time (pull and pull and pull).

here is what I have done to try to remedy the problem:
1. changed filter elements
2. changed plugs
3. rebuilt carb with rebuild kit (on one of them)
4. removed carbon from exhaust ports
5. soaked mufflers in gas to try to break up any carbon
6. checked throttle lines and re-adjusted
7. removed carbs and cleaned with gas (removed gunk build up).
8. sprayed them with carb cleaner

So far every remedy above helps for awhile, then same problem, my next move is to change the fuel filters.

I should mention that I started having these problems after switching to Opti 2 oil from no smoke, I am now going to switch back to no smoke or redmax oil.

Can anybody see anything I have missed or know of something else I can do? This is starting to really irritate me, nothing worse than pulling on equipment.

[UNISCAPER]

kels:

How ong have you had them? If a two storke gets worn rings, no matter what you do, and how good the spark is, they won't fire. Used to happen every year with Echo products, and after we put on a new block or rings, they would fire right up. Can you pull a compression check and see where you are at?

[kels]

Thanks uniscaper, I have been using these two trimmers for the last 1.5 years. I just checked the compression and it read right at 100psi. I think that is where it is suppose to be.

[kels]

I think the problem is fixed. Took the muffler off of the stik edger and put on one of the trimmers that was not cranking, trimmer fired up on third pull, took old muffler and a friend cut it in half, the carbon was unbelievable. Bought new muffler and it now cranks. I hope this will solve the problem, until I need another muffler.

I was told that if you take the trimmer guards off, carbon will build at a more rapid rate. When the line is futher out than the the guard cutt off allows the engine cannot run at a high enough rpm to burn it out. I am now a believer.

Hope this helps someone in the future.

[Honda Jesus]

Kels,

Makes sense to me, plugging the muffler w/carbon is just like putting a potato in the exhaust pipe of your truck.

[grassworks]

Usually there is a Spark Arrestor Screen that can be replaced or removed on/in Muffler. The Screen clogs with build up shortly and causes these type problems. Removing screen fixes problem 9 out of 10 times.

[dishboy]

I used to have to do regular exhaust port cleaning with opti, but I ran it at 2 oz per gallion, using Amsoil at 2.6 oz per gallon port maint. is almost nill.