Husqvarna 128 LD Spark Plug Problems?

[medic2575]

Hey Guys
Im working on the above trimmer. The gas of course sat up in it and it wouldn't start. Pulled the carb and tore it down and gaskets and diaphrams were trash and carb was dirty. Looked at a G&D kit and it was a little less than a new carb so no brainer. I replaced the carb and the thing runs like crap. The lady that owns the trimmer had just install a FastFire FF-11 new plug. Have any of you had any problems with these plugs. When I went to crank the trimmer it only boggs and backfires and I cant get it to clear up. I removed the muffler and it and the spark arrester are clean and clear. Cylinder walls are pristine. Any help or advice would be appreciated.
PS: My understanding is that this trimmer can run a Champion RCJ8Y. Is that right?

 

[066]

PS: My understanding is that this trimmer can run a Champion RCJ8Y. Is that right?[/QUOTE]

try a Champion RCJ6Y or NGK BPMR7A sparkplug set the gap at .5mm

 

[mechanic mark]

128LD HUSQVARNA TRIMMER Manual | SearsPartsDirect see page 20 RCJ-6Y

 

[medic2575]

128LD HUSQVARNA TRIMMER Manual | SearsPartsDirect see page 20 RCJ-6Y

Hey Guys.

I tossed the Torch spark plug and put in a Champion plug and it fired right up and runs like a new one. The guy at the mower shop that's a Husqvarna dealer told me that the Torch plugs just wont run in the Husqvarna trimmers. He stated that when they get one in to their shops that wont run, run roughly or wont idle that the first thing they do id replace the torch plug and it usually fixes it.
This is just for future reference for anyone that might run into this problem in the future. Thank for the guys that responded to this thread and your willingness to help.

 

[harcore]

I have a 128LD trimmer and did the following to try and fix the engine from continually bogging and eventually dying. I changed or cleaned the gas, filters,spark plug, exhaust port, fuel lines, tank filter and took the carb off 3 times to try and fix this problem. I was STUMPED! After reading an obscure post somewhere on the internet, I heard that a guy would stop have problems when he hooked the trimmer to a coil tester. I also read that the trimmer would not run without a resistor spark plug. The fix for mine was to hook an alligator clip to the plug and then insert the other side in the spark plug wire. It ran perfect! I am guessing that the spark plug wire somehow interferes with the coil or ignition system. I would try this first if having problems with this trimmer dying. It is easy and will save you a lot of headache! now to figure out how to get it running without an alligator clip on it. :wink:

 

[bertsmobile1]

Small hand deld engines run at crazy speeds.
So they are very sensitive to both the grade of plug used and the gap.
Almost no one ever bothers to check the gap and new plugs may not be gapped correctly for your engine.
I only fit NGK Champion or Bosch plugs and have found Champions tend to run better in 2 stroke hand held engines.
So over the years I have not been reordering NGK 2 stroke plugs or Champion 4 stroke plugs.

 

[primerbulb120]

Bert, I've had excellent results with Champion in both 2 and 4 cycle applications. Curious as to why you are not using Champion in the 4 cycles?

I've had the most failures overall with NGK. Particularly in Echo blowers and Honda GC/GCV series engines.

 

[primerbulb120]

I have a 128LD trimmer and did the following to try and fix the engine from continually bogging and eventually dying. I changed or cleaned the gas, filters,spark plug, exhaust port, fuel lines, tank filter and took the carb off 3 times to try and fix this problem. I was STUMPED! After reading an obscure post somewhere on the internet, I heard that a guy would stop have problems when he hooked the trimmer to a coil tester. I also read that the trimmer would not run without a resistor spark plug. The fix for mine was to hook an alligator clip to the plug and then insert the other side in the spark plug wire. It ran perfect! I am guessing that the spark plug wire somehow interferes with the coil or ignition system. I would try this first if having problems with this trimmer dying. It is easy and will save you a lot of headache! now to figure out how to get it running without an alligator clip on it. :wink:

Husqvarna 128LD's have problematic ignition systems. I've had more ignition related issues with these than on any of the other common 2 cycles. Sometimes it's the coil itself, sometimes the spark plug, sometimes the coil wire, occasionally the stop switch, and often two or three of the above items. And yes, the problem will often magically disappear when I connect something between the coil and plug (usually my spark tester.)

Unfortunately I don't have a clear diagnostic pattern for you. I have enough good used parts that I just replace things till the problem goes away. The main point of my post is that any of the ignition components could be causing the issue.

 

[bertsmobile1]

Bert, I've had excellent results with Champion in both 2 and 4 cycle applications. Curious as to why you are not using Champion in the 4 cycles?

I've had the most failures overall with NGK. Particularly in Echo blowers and Honda GC/GCV series engines.

When I kicked off I inherited a box with about 50 plugs in it.
So I bought a Stens Champion plug deal .
450 spark plugs that were popular 20 years ago with free dispensor, and needless to say I still have 2/3 of them left.
Then RGS did a deal on NGK's similar 340 plugs + dispensor, good thing is these plugs mostly were the ones I actually needed.
SO slowly I am widening the range , no need to keep equivalent plugs & I am conversant with NGK nomenclature so have no troubles finding a slightly hotter / colder plug.
The Bosch came in a deal at a swap meet, again with a dispensor.
Looks good on the wall and I have to buy Champions is 4's & NGK's in 10's to get wholesale pricing so it keeps the extras nicely sorted.

 

[ILENGINE]

Bert, I've had excellent results with Champion in both 2 and 4 cycle applications. Curious as to why you are not using Champion in the 4 cycles?

I've had the most failures overall with NGK. Particularly in Echo blowers and Honda GC/GCV series engines.

I have had the opposite issues. I won't touch a Champion unless I don't have other options. Having to deal with 50 bad plugs in one day tends to sour your opinion on a brand. I have had a few issues with the BPMR7A failing a few minutes after installation in a few saws and trimmers but nothing like Champion failures.