Saw builds

[jmssaws]

Pump diaphragm?

I keep thinking carb but I rebuilt 2 different ones that didn't help and it's got a brand new complete oem carb on it now and still ain't right.

 

[huskihl]

Look for a crack in the rubber lines. And put a zip tie on the ends where they go on the barbs maybe. My 7900 would run with the impulse line burned off. Something was wonky and I shut it off in time

 

[jmssaws]

This saw isn't terrible but somthin is wrong with it, it's down on power and acts silly,I'm sure it's a airleak. Maybe
Can of eather is fixing to tell me where

 

[jmssaws]

I can't find a airleak and I don't think I put 3 bad carbs on it but stranger things have happened.

 

[srcarr52]

Coil?

 

[jake wells]

i have seen tank vents cause some unusual problems have you checked that?

 

[srcarr52]

I've also seen partially blocked impulse lines do something similar.

 

[dall]

could the case gasket be bad jason ?

 

[jmssaws]

Coil?

I have not changed that.
It does seem worse warm.
Did you check compression on this saw?
I'm curious

 

[jmssaws]

Tank vent is new.
Eather will find a airleak so I don't think it has one.
It tunes around 1 and 1 with every carb I've tried.

 

[jake wells]

bad secondary winding in the coil causing it to run on primary start side of the coil. only seen that in 2 stroke mowers though

 

[jmssaws]

It's down on power and 1 out of every 5 times I check for a 4stroke it won't be there. Impossible to get a good solid idle,it's either fat or lean

 

[jake wells]

that sounds like a leak to me start it and take the starter off and spray around the base.

 

[jmssaws]

that sounds like a leak to me start it and take the starter off and spray around the base.

Way ahead of ya

 

[jake wells]

Way ahead of ya

well swap the coil jason.

 

[jmssaws]

Has to be a airleak at the carb,only place I didn't check

 

[jmssaws]

Even though I ain't found one I still think it's a airleak.

 

[jake wells]

swap the intake boot?

 

[huskihl]

Throttle shaft could be worn. My 670 was sucking air there

 

[jake wells]

yeah but he put a new carb on it and it still had the problem.