Help: MS 460

[Donald]

I'm quite frustrated and hope to find some real answers here. I bought a brand new 460 last year and after 6-8 hrs of use, the motor blew. I use premium gas with ultra stihl oil mix. The warranty covered the rebuilt. After using it for about an hr, the motor quit. There was no compression. I took it in to a different shop. They cleaned it up and said the compression is great. They even ran the motor front of me with a tachometer showing the correct rpm ranges. They didnt even charge me for the quick lookover and minor carb adjs. Then yesterday after making 5 cuts (15-20 mins), the motor quit again. I was so disgusted I didn't even try again. Will drop it off perhaps tmw am. I've used saws for a long time. I know enough on how to maintain and run them. I've had no problems with my other saws. It just seems when it gets "hot", it quits. The shop doesnt have any wood so they can't really test it.

Thanks in advance

Donnie

 

[Trx250r180]

id check or replace the fuel line ,they get soft and colapse when running sometimes

 

[showrguy]

sounds like maybe a bad coil ??

 

[Jacob J.]

Sounds like it may be a problem related to the ignition. When a two-stroke motor gets hot and quits, but still has compression- the ignition is the next thing
you want to check.

 

[nmurph]

id check or replace the fuel line ,they get soft and colapse when running sometimes

I did a fuel line on a tree service 440 last week that did the exact same thing.

It's easy enough to fish it out of the tank and give it a feel.

 

[tommyus4]

This thread from a few days ago.

http://www.arboristsite.com/chainsaw/200308.htm

 

[Bowtie]

I did a fuel line on a tree service 440 last week that did the exact same thing.

It's easy enough to fish it out of the tank and give it a feel.

And also cheap enough to replace!

 

[ClyderGerman]

they get soft and colapse when running sometimes

 

[pro94lt]

what vents a 460's fuel?

 

[galde]

Is your premium 100% gasoline? Ethanol can make short work of fuel lines, primer bulbs, carburetor components,.... If a premium pump is dispensing ethanol, it is more likely to be older gas than the regular pump, since less premium is used nowdays because of fuel prices.

 

[Donald]

Update: Found the problem!

The compression drops as the motor runs hot. He will order parts and have it ready by next week. Best part is that it is under warranty. What causes compression to drop? bad gasket?

Thanks for all your inputs.

Donnie

 

[kyle1!]

If that is a brand new saw with that little of run time take that lemon back to the dealer for another.

Brian