Can't start my 92cc saw

[grack]

288 for me couldn't see the damage felt great though it was before i had a tester.

 

[jmssaws]

I just ported a 661 that the owner thought ran great,had 120lb but started and ran fine.

 

[davhul]

Then when it finally gets to around 90-100 it's hard to start and idle. But by that point you can tell by just pulling the rope something is wrong.
Another note I've seen bad port chamfers wear the rings to a taper from top to bottom. Not saying that's bedfords problem but I have seen it.

 

[blsnelling]

Just pull the cylinder and take a look. It only takes 5-10 minutes.

 

[Bedford T]

well fellas the good news is the plug stayed dry and fuel did not pour out of the bowels of the saw so i would say with confidence that issue is fixed, but it still will not crank. I am going to follow with my plan of testing the coil and i should be able to do that tomorrow and if it tests bad we know it will soon start and if the coil tests good i will pull the jug off and check the crank bearing and figure out how to check squish and check cylinder and piston and rings. if i pull the jug i may have to wait until the following day to put it back on. just telling you up front.

the compression is high

thank you all for helping ,me along.

on the squish i know where the squish ring is and i guess i just need to rig something to measure the opening

 

[grizz55chev]

What is the comp #?

 

[Bedford T]

What is the comp #?

please read #37,

 

[jmssaws]

If the plug is dry it's not running because it's not getting gas now.
The coil on these saws rarely go bad and when they do they don't work period.

 

[3000 FPS]

What is the comp #?

Yep that is a good question. Might as well be spitting in the wind with out it.

 

[davhul]

Have a question. Does anyone ever do a cylinder leak down? That would show any ring and cylinder damage from the top of the exhaust port to tdc.

 

[Trx250r180]

Have a question. Does anyone ever do a cylinder leak down? That would show any ring and cylinder damage from the top of the exhaust port to tdc.

You can cap the intake and exhaust and hook a mityvac tool to the impulse barb and pump some psi into the case and sparay soapy water around to look for leaks ,the way the cylnider has ports all over be hard to do a leakdown like a car .

 

[davhul]

True about the ports. But I check above the exhaust port were compression is made

 

[Trx250r180]

True about the ports. But I check above the exhaust port were compression is made

If could lock the engine so it did not spin over should be doable ,but i have had saws with 170 psi and rings were melted to the piston ,can get same check popping the muffler cover off and looking at the piston ,same through the intake ,If have one of these cameras can spy inside also

 

[grizz55chev]

What is the comp #?

The question is still what the comp #is, the stihl techs opinion does not state a #. It's been my experience that a marginal comp saw will exhibit some of the problems you are seeing. If you don't have a comp guage maybe you could borrow one from your local parts store. Good luck.

 

[3000 FPS]

The question is still what the comp #is, the stihl techs opinion does not state a #. It's been my experience that a marginal comp saw will exhibit some of the problems you are seeing. If you don't have a comp guage maybe you could borrow one from your local parts store. Good luck.

Amen.

 

[grizz55chev]

Bump, any news?

 

[grizz55chev]

OP gone silent?

 

[3000 FPS]

OP gone silent?

I am biting my tongue.

 

[grizz55chev]

Any progress Bedford T? Inquiring minds.

 

[ncfarmboy]

I am biting my tongue.

I'm done.
Shep