Shindaiwa 488 runs for a little then dies...symptoms. ....

[Tifford]

Hello,
Here are my symptoms for my 488 shinny.
1. It starts
2. It runs for maybe 2 minutes then dies
3. If I let it rest for a while it will start up again
4. I noticed that gas is leaking under the metal on/off switch where there is a gap between the handle and the engine compartment.
5. The chainsaw feels like it has a ton of compression. I'm a fairly big guy and it takes a lot to crank it over.

It has a wall Boro carburetor. The same fuel is used in another shindaiwa 488 and it ran fine today.

I opened up the top part today. On the left side of the carburetor I believe is the fuel intake. It is just behind here that I saw fuel coming out of the saw. On the right side of the carburetor I believe is a return to the gas tank fuel line. When I look inside the gas tank I only see the fuel line with the filter attached.

I took the fuel delivery line out and it seems to not have any cracks in it. However the grummet that is apart of the fuel intake line has what appears to be a small defect in it.

When I start both 488s with the same fuel, I noticed the leaky one put out a little more smoke then the one that runs fine.

 

[fearofpavement]

I'd check the small screen inside the carb as a starting point.

 

[Tifford]

It will be the first thing I'll check Sunday morning. Thanks!

 

[buzz sawyer]

I was given one of these by a friend. Seemed rather sluggish so I opened the carb up and found sawdust packed under the metal cover for the inlet diaphragm - thought that would cause it to run rich. Cleaned it all out and it was fine.

 

[alderman]

I believe the second line you are talking about is an impulse line.


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[Thommo]

Check for spark when it stops. It could be the coil breaking down when it gets hot

 

[Matto]

I got the same symptoms on another saw. You should check the fueltank vent. Sometimes they got clogged. So after turning the engine on, the gastank runs vaccum and engine dies by lack of fuel.

After cleaning or replacing the gastank vent, also check the rest of the fuel line and gas filter.

 

[Tifford]

Just wanted you guys to know I haven't forgotten about you. Chainsaw is on hold while I deal with Murphys Law concerning other things.

 

[HarleyT]

Sounds like you need to replace your fuel line and go through/rebuild the carb.

Here is a pic of the Wall Boro Man......

 

[grizz55chev]

Sounds like you need to replace your fuel line and go through/rebuild the carb.

Here is a pic of the Wall Boro Man......

View attachment 573216

That's pretty efin funny right there!

 

[Chainsaw Jim]

I also suspect it may be the coil. Venting problems don't usually wait that long and once a carb needing rebuilt dies in the cut it usually won't allow it to fire again until rebuilt.
You should also check the condition of the piston through the exhaust and or intake.

 

[HarleyT]

4. I noticed that gas is leaking under the metal on/off switch where there is a gap between the handle and the engine compartment.

Coil??? Naahh...

 

[HarleyT]

Here is the tank.. Fuel line...

 

[HarleyT]

Here is the switch area...

 

[HarleyT]

Yes, running a saw until it dies....
Go ahead and peek at the piston.
If it looks OK, go through the fuel system correctly....

 

[Chainsaw Jim]

Yes, running a saw until it dies....
Go ahead and peek at the piston.
If it looks OK, go through the fuel system correctly....

My apologies, I should have cleared that advise with you first.

 

[HarleyT]

What is your advice? Buy a new coil and see if that cures it?

The overheating coil theory is a poor one anyway....