# BG86C wont rev



## Marlin_Mechanical (Dec 13, 2021)

I've got a customers BG86C blower in as it would start and run on choke but would die as soon as you give it any throttle. Its a fairly new fault as its a 2016 model and he's been using it commercially with no problems until a week or so ago.
I've don the usual things, checked for air leaks in the fuel line, replace the air and fuel filter, replaced the plug, checked the spark strength and all seems good. After cleaning the carb in the ultra sonic tank and putting me gaskets and diaphragms in, it still was no better so I chucked a new pattern carb on and it would keep running but not rev very high.
I then removed the exhaust which looked a bit coked up but not to bad but it did have a rattle inside. I fired the blower up without the exhaust and it ran perfectly so a new silencer was ordered. That turned up this morning and after fitting it I'm back to it not revving and dying once it drops back to idle.

(Edit) I should add I've put fresh fuel in and tried swapped it out for Alkylate fuel
What am I missing, every thing seems good but It just wont play ball!

Stew


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## frank_ (Dec 13, 2021)

crank seal maybe stew ?


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## lone wolf (Dec 13, 2021)

Marlin_Mechanical said:


> I've got a customers BG86C blower in as it would start and run on choke but would die as soon as you give it any throttle. Its a fairly new fault as its a 2016 model and he's been using it commercially with no problems until a week or so ago.
> I've don the usual things, checked for air leaks in the fuel line, replace the air and fuel filter, replaced the plug, checked the spark strength and all seems good. After cleaning the carb in the ultra sonic tank and putting me gaskets and diaphragms in, it still was no better so I chucked a new pattern carb on and it would keep running but not rev very high.
> I then removed the exhaust which looked a bit coked up but not to bad but it did have a rattle inside. I fired the blower up without the exhaust and it ran perfectly so a new silencer was ordered. That turned up this morning and after fitting it I'm back to it not revving and dying once it drops back to idle.
> 
> ...


Take the new silencer off and tell what happens.


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## Automender (Dec 13, 2021)

I personally have a BG86C and it did the exact same thing. It was the spark arrester was coked up bad. Check the arrester on both mufflers, new one could be damaged. The arrester screws out just like a sparkplug using same socket.


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## Marlin_Mechanical (Dec 14, 2021)

It runs much better without the silencer off. 

The spark arrester doesn't look to be removable on the exhaust fitted to this blower


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## frank_ (Dec 14, 2021)

Marlin_Mechanical said:


> It runs much better without the silencer off.
> 
> The spark arrester doesn't look to be removable on the exhaust fitted to this blower


was the new carb the later strato one with the plastic divider insert ?


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## lone wolf (Dec 14, 2021)

When running is it down by around half the rpms as normal?


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## Marlin_Mechanical (Dec 14, 2021)

frank_ said:


> was the new carb the later strato one with the plastic divider insert ?


Its a Zama S261


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## Automender (Dec 14, 2021)

Marlin_Mechanical said:


> It runs much better without the silencer off.
> 
> The spark arrester doesn't look to be removable on the exhaust fitted to this blower


This is a pic of my spark arrester. It unscrews. Based on my experience you would have to toss the muffler every few years because the internal screen plugs up if it wasn't removable My blower is about four years old.
.


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## Marlin_Mechanical (Dec 14, 2021)

lone wolf said:


> When running is it down by around half the rpms as normal?


I doubt it even gets to half revs


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## Marlin_Mechanical (Dec 14, 2021)

Automender said:


> This is a pic of my spark arrester. It unscrews. Based on my experience you would have to toss the muffler every few years because the internal screen plugs up if it wasn't removableView attachment 948379
> .


The outlet on the original and the brand new silencer is brazed in to place and has no hex on this one


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## Marlin_Mechanical (Dec 14, 2021)




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## frank_ (Dec 14, 2021)

Marlin_Mechanical said:


> Its a Zama S261


there were 2 types (0606 or 0600 iirc)
non strato, have youtried the old carb now that the silencer is sorted ?


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## frank_ (Dec 14, 2021)

i dont think uk spec have any spark arresters


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## lone wolf (Dec 14, 2021)

Marlin_Mechanical said:


> I doubt it even gets to half revs


I think its the coil.


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## Marlin_Mechanical (Dec 14, 2021)

frank_ said:


> there were 2 types (0606 or 0600 iirc)
> non strato, have youtried the old carb now that the silencer is sorted ?


No, I'll try swapping it back in the morning when I'm back at the workshop.


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## Automender (Dec 14, 2021)

I found a you tube video when I was looking for a solution to my issue. It is about not able to rev up to higher RPMs it said easy fix. You can search for under BG86c problems. It would not play on other sites.


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