Stihl KM85 Kombi engine troubles

[chrisj]

Thanks Gardenkit. Oil and mix are the same as ever. The exhaust didn't seem loose at all but I'll check again tomorrow. There are ways to spend a rainy Saturday than tinkering with machinery.

As I say it's 9 years old and was due replacement anyway. I have worked it really hard the last week or so, so I think something has just failed finally. It would be nice if I can fix it up as a spare though.

[doobin]

Don't replace it with 4-mix (FS90, 100 or 130), replace it with 2-mix. FS-70 or FS-94 are the equivalent power. Drop the engine straight on the old kombi shaft.

 

FS-85s were good solid engines. I ran them as kombi tools until the 2-mix engines came out.

[GardenKit]

Don't replace it with 4-mix (FS90, 100 or 130), replace it with 2-mix. FS-70 or FS-94 are the equivalent power. Drop the engine straight on the old kombi shaft.

 

FS-85s were good solid engines. I ran them as kombi tools until the 2-mix engines came out.

Haha, you really do not like 4 mix do you?

 

Must admit I agree with you though.

[doobin]

Haha, you really do not like 4 mix do you?

 

Must admit I agree with you though.

 

It's no-brainer, the 2-mix engines are also cheaper than the 4-mix.

[chrisj]

Yes I've been following the other thread discussing 4 mix.

[chrisj]

Thanks Gardenkit I think you may have had it. The exhaust was plenty tight, but looking closely the oily yuck was between the engine fins on both sides level with the exhaust port, and taking the exhaust off the gasket looked pretty crappy. So first step looks to be a new gasket for the exhaust and then see where we're at.

[GardenKit]

Thanks Gardenkit I think you may have had it. The exhaust was plenty tight, but looking closely the oily yuck was between the engine fins on both sides level with the exhaust port, and taking the exhaust off the gasket looked pretty crappy. So first step looks to be a new gasket for the exhaust and then see where we're at.

Better check that the exhaust is not blocked, if so it will put a pressure on the gasket resulting in a blowpast.

 

Exhausts are often blocked by burnt oil deposits caused by oil of insufficient quality or excessive quantity.

[chrisj]

Thanks for the tip, I'll check. I always use Stihl oil so quality should be fine.