# Stihl SR 450 Sprayer/Blower CARB Adjustment Tool?



## poleandpro (Jul 20, 2016)

Hi there. I have a new Stihl SR 450 'sprayer'. It's a nice machine, except it really needs to come from the factory with a Hip Belt and Chest Strap. The thing weights 60+ pounds fully loaded and top-heavy; can't imagine working all day with it, in hot conditions, maybe on uneven ground without a proper support system.

Anyways, I am looking for the part number for the *Carb Adjustment Tool*. I've checked online and see there are several different versions (usually for saws) but haven't found the right one for their blowers/sprayers.

I'm hoping for the OEM tool; I've spent too much time in my life with drywall screws, picks and plyers, and at this point, just want the right tool for the job!

Can someone point me in the right direction?

Thank you very much


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## DND 9000 (Jul 21, 2016)

You need screwdriver 5910 890 2305 for adjusting the carburetor, that`s the OEM tool. The screwdriver looks like this: (see the file attached)


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## Definitive Dave (Jul 21, 2016)

If this is a new piece of equipment be aware that removing the limiter caps likely voids the warranty completely.
The screwdriver DND references will adjust the carb within the limits of the caps.
Adjusting the running of this piece of equipment will probably have unintended results as I believe they are calibrated to spray at a certain RPM.
I don't have a single PDF for this model only Mediacat.
Hopefully someone sends you a service manual soon.
IF IT IS NEW TAKE IT TO THE DEALER.
Dave


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## DND 9000 (Jul 22, 2016)

If you tune your carburetor on your SR 450: idle speed is 3000 and max engine speed with nozzle attached is 6800


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## poleandpro (Jul 26, 2016)

Thanks for the replies!

I am still trying to find the service manual for the SR450. It seems like it's not as popular as Stihl saws and regular blowers. From my local dealer I understand that at least around where I live, 95% of the purchases of these sprayers/blowers have been by the really big pest control companies like Orkin, and the Mosquito-specific companies like "Mosquito Joe". In talking to the dealer, I believe they tuned it like they would a chainsaw (going to 4 stroking at full throttle), rather than tuning to a specific RPM to achieve a certain spray rate.

Basically, I don't think they are used to a landowner/homeowner like myself even using an SR450. I've got 15 acres to treat, some with apple trees, some pear trees, and a whole bunch of woods and mosquitoes!

I have a tach, so DND 9000, thank you for the 3,000 RPM and 6,800 RPM figures.


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