stihl runner but no winner!

[mad matty]

Hi all looking for some advice what to do next!!!

 

Been given an 044 by a customer its in great condition was running ok, but now wont rev out fully or tick over quite right.

 

what I,ve done so far is carb diaphragm kit, cleaned carb with carb cleaner, new plug, cleaned breather and air filter, run it up with fuel cap loose.

 

could it be it needs a rebuild????

any advice much appreciated......thanks in advance Matty.

[spudulike]

Hi all looking for some advice what to do next!!!

 

Been given an 044 by a customer its in great condition was running ok, but now wont rev out fully or tick over quite right.

 

what I,ve done so far is carb diaphragm kit, cleaned carb with carb cleaner, new plug, cleaned breather and air filter, run it up with fuel cap loose.

 

could it be it needs a rebuild????

any advice much appreciated......thanks in advance Matty.

 

Look at the piston after removing the muffler, sounds as though it may have nipped up.

 

Other than that, perhaps the carb needs ultrasonically cleaning.

[mad matty]

Look at the piston after removing the muffler, sounds as though it may have nipped up.

 

Other than that, perhaps the carb needs ultrasonically cleaning.

 

Thanks for the reply Spud, when I remove the exhaust am I looking for damage to rings and piston?

Also if new is required is it worth going for a new barrel as well, I suppose it depends on damage?

where would you suggest getting one from as so many Chinese copies

thanks again Matty.

[spudulike]

As far as piston damage goes, both skirt and ring will reduce compression but the rings will reduce it considerably more.

 

You are looking for vertical lines on the exhaust side of the piston. If it looks like wet smooth aluminium, all is probably fine.

 

I usually salvage the OEM cylinder and fit a Meteor piston and have a very high success rate:thumbup:

[agg221]

Have you done anything with the fuel line from the tank to the carb? If not, I would look at changing the line and filter as the symptoms suggest it may not be pulling fuel through evenly and can't meet full demand.

 

Alec

[mad matty]

Have you done anything with the fuel line from the tank to the carb? If not, I would look at changing the line and filter as the symptoms suggest it may not be pulling fuel through evenly and can't meet full demand.

 

Alec

 

Hi Alec yes mate have changed tank filter and blown pipe through with airline

thanks Matty.

[mad matty]

Have had exhaust off, can see a very slight scar on piston.....thinking of maybe putting another piston in it, also has anyone ever used hutzl pattern carbs, any good? Also maybe fitting a dual port exhaust just for good measure.

[spudulike]

Have had exhaust off, can see a very slight scar on piston.....thinking of maybe putting another piston in it, also has anyone ever used hutzl pattern carbs, any good? Also maybe fitting a dual port exhaust just for good measure.

 

Small marks/scratches are not an issue - look on my "what's on your bench" thread, plenty of seized pistons on there - the sort of look you don't want to see is the look that someone has attacked the piston with a course file - with black carbon embedded in it!

 

If unsure, post a pic:thumbup:

[mad matty]

Small marks/scratches are not an issue - look on my "what's on your bench" thread, plenty of seized pistons on there - the sort of look you don't want to see is the look that someone has attacked the piston with a course file - with black carbon embedded in it!

 

If unsure, post a pic:thumbup:

 

 

Hi, Spud

Thanks for the replies.....The piston looks fine to be fair the mark on the piston is nothing like the pics in your post, Will go down the carb route first and try a new carb or borrow one?

Really appreciate your help and advice!!

Cheers Matty.

[wyk]

Hi, Spud

Thanks for the replies.....The piston looks fine to be fair the mark on the piston is nothing like the pics in your post, Will go down the carb route first and try a new carb or borrow one?

Really appreciate your help and advice!!

Cheers Matty.

 

Did you replace the fuel filter? I didn't see you say that. Also make sure the fuel line is healthy, and not easily squished. Old fuel lines will partially or fully collapse at full throttle sometimes.