# Stihl 4 mix compression low but runs fine?



## Dean Thompson (Nov 23, 2019)

Ok so got my self a compression tester to check my stihl 4mix gear and bear in mind that they all run as should and start within a couple of pulls even though one does seem easier to pull than the rest but works well i read that people say any stihl that reads under 100psi is nackered and will not start wish i realise is completley untrue as i tried 2 km 130s a brand new hl 95 and a fs 100 all came back with a 60psi reading also done a ts 410 which ran well done 100psi 

What does other peoples 4 mix test show for psi out if intrest also i had choke open and throttle wot and i keep all my gear well serviced and valve checked all time thanks


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## frank_ (Nov 23, 2019)

decompessor kicking in maybe dean ?


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## Brushwacker (Nov 23, 2019)

frank_ said:


> decompessor kicking in maybe dean ?


I wouldn't trust those readings.
Plenty of junk compression gauges out there.


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## Dean Thompson (Nov 23, 2019)

frank_ said:


> decompessor kicking in maybe dean ?


Didnt lnow they had decompressors tbh mate ?


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## Dean Thompson (Nov 23, 2019)

Brushwacker said:


> I wouldn't trust those readings.
> Plenty of junk compression gauges out there.


Amean it could be mate it is brand new but also a cheap one but has good reviews amean a would have thort that maybe if the tests wer all diffrent but the fact the 4 mix all come up the same 60 psi and the only diffrent one waa the 410 thts understandable


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## frank_ (Nov 23, 2019)

Dean Thompson said:


> Didnt lnow they had decompressors tbh mate ?


usually a finger on the exh cam lobe, you may need to open the exh clearance to 2mm or so to get a compression reading


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## Justin Taylor (Nov 24, 2019)

frank_ said:


> usually a finger on the exh cam lobe, you may need to open the exh clearance to 2mm or so to get a compression reading


 just got to warn it up then do it


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## frank_ (Nov 24, 2019)

Justin Taylor said:


> just got to warn it up then do it


centrifugal aint it justin ? (on the left of the lobe)


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