Stihl BR700 backpack blower

[Jonsey13]

Purchased earlier this year, used daily for a few hours a day, more in the winter, was a really powerful blower when new, but all of a sudden has lost some power, cleaned fuel tank and changed filters, air filter, but still not much difference, have not done the valve adjustment yet to see if this would make any difference, anyone had similar problems and a fixable solution?

[ChunksBigBro]

What colour / brand / type of 2 stroke oil are you using?

[Jonsey13]

4 hours ago, ChunksBigBro said:

What colour / brand / type of 2 stroke oil are you using?

Green super stihl oil, and run aspen every 4-5 tank

[Stubby]

15 minutes ago, Jonsey13 said:

Green super stihl oil, and run aspen every 4-5 tank

I would suggest using Aspen for every tank or not at all . The pump fuel will have removed the coating on the rubber components  ( that is put there to keep it supple ) but continue to keep them supple as it is slowly dissolving them .  Aspen wont remove the coating if used from the get go but  but won't keep it supple if used intermittently with pump fuel . 

[Jonsey13]

31 minutes ago, Stubby said:

I would suggest using Aspen for every tank or not at all . The pump fuel will have removed the coating on the rubber components  ( that is put there to keep it supple ) but continue to keep them supple as it is slowly dissolving them .  Aspen wont remove the coating if used from the get go but  but won't keep it supple if used intermittently with pump fuel . 

Do you reckon this is the cause for the loss of power?

[Stubby]

Just now, Jonsey13 said:

Do you reckon this is the cause for the loss of power?

No idea bud but ..... pump fuel will over time , and I mean over time dissolve the rubber components . This is sometimes made more apparent when people switch to Aspen after a saw has been run on pump fuel for a long time .

[ChunksBigBro]

Ok right oil, biggest cause out! May be unrelated but in the past month we have had to replace in 2 of our blowers the plastic cam that controls the valves. The small metal piece that comes out centrefugally ( if thats even a word) was getting stuck out which was knocking the exhaust valve at the same time as the other valve, causing low compression. Our fitter did it, i just get the reports, so im not sure the ins and outs of it all ( nor am i a fitter) but that solved low power issues

[Jonsey13]

1 hour ago, ChunksBigBro said:

Ok right oil, biggest cause out! May be unrelated but in the past month we have had to replace in 2 of our blowers the plastic cam that controls the valves. The small metal piece that comes out centrefugally ( if thats even a word) was getting stuck out which was knocking the exhaust valve at the same time as the other valve, causing low compression. Our fitter did it, i just get the reports, so im not sure the ins and outs of it all ( nor am i a fitter) but that solved low power issues

Have used the stihl super on the recommendations of my local stihl dealer ?, time to find my receipt and see if it’s still in warranty!, if out, if you see your fitter, could you ask if it’s a straight forward job to

fix myself please ??

[Jonsey13]

1 minute ago, Jonsey13 said:

Have used the stihl super on the recommendations of my local stihl dealer ?, time to find my receipt and see if it’s still in warranty!, if out, if you see your fitter, could you ask if it’s a straight forward job to

fix myself please ??

Was the 2 blowers you had fixed Br700?

[ChunksBigBro]

600’s, back plates off, fan and flywheel off ( its sort of dog bone / peanut shaped not round) , ribbed casing off ( its square) and its the plastic cog in there, £10 to buy. Plus some red gasket sealant, takes him an hour, plus 24 hrs for sealant to dry, OR take it to a workshop if ur not to adventurous