Ms460

[Molly12345]

I have rebuilt two ms460’s. I have good compression, spark and put fuel in cylinder can’t get them to start. Pressure and vacume tested took carb apart and replaced everything still no start. Could it be timing where should magnets be at top dead center?

 

[grizz55chev]

I have rebuilt two ms460’s. I have good compression, spark and put fuel in cylinder can’t get them to start. Pressure and vacume tested took carb apart and replaced everything still no start. Could it be timing where should magnets be at top dead center?

OEM or aftermarket?

 

[cookies]

you added fuel and still no pop tells me its spark timing or no spark, the fact you did it twice tells me you did something that kills spark or changed the spark timing such as coil to flywheel gap, coil kill wire, flywheel key etc

 

[grizz55chev]

you added fuel and still no pop tells me its spark timing or no spark, the fact you did it twice tells me you did something that kills spark or changed the spark timing such as coil to flywheel gap, coil kill wire, flywheel key etc

Or it's aftermarket with lots of squish, and it's flooded.

 

[lone wolf]

you added fuel and still no pop tells me its spark timing or no spark, the fact you did it twice tells me you did something that kills spark or changed the spark timing such as coil to flywheel gap, coil kill wire, flywheel key etc

Or he flooded it. Clean the plug dry the saw out try again.

 

[Catfish044]

Loosen the coil , put a business card between the coil and flywheel ,torque her down
Double check wires to kill switch

 

[Molly12345]

OEM or aftermarket?

Oem mostly meteor piston and cylinder

 

[3000 FPS]

You need to pull the plug and see if it is wet or dry.
Also you can put a little fuel mix down the carb hold it at wide open throttle and see if it tried to start.
I would also do a compression test.
Something is missing. Spark, fuel, or compression. Has to be one of the three.

 

[3000 FPS]

One of the things I do and to take the top cover off to expose the cylinder. Pull the plug and hold it side ways on top of the cylinder with the plug attached to the plug wire and then pull it over to see if there is a spark at the plug.
Also double check the plug for ,025 gap.

 

[Catfish044]

Oops just read that post again said ya had spark , I like a spark tester you can adjust the gap , sometimes a half ass plug will make spark pulled out and laid against the cylinder ,but once you install in the cylinder and it’s subject to compression and air/fuel mixture she won’t do it , can’t tell how man times the guys bring the demo says in with this problem

 

[3000 FPS]

Oops just read that post again said ya had spark , I like a spark tester you can adjust the gap , sometimes a half ass plug will make spark pulled out and laid against the cylinder ,but once you install in the cylinder and it’s subject to compression and air/fuel mixture she won’t do it , can’t tell how man times the guys bring the demo says in with this problem

There is something missing and is sounds to me like it is time to double check everything.
Putting a little fuel down the carb tells me a whole lot about what is going on.
If it tries to fire then I know right off that the spark is good and compression is good but fuel is not.
If it does not fire and he pulls the plug and it is wet then chances are no spark or bad compression.
Then time to put a compression gauge on it to see what it is. You cannot tell by feel on pulling the rope.

 

[grizz55chev]

Oem mostly meteor piston and cylinder

Did you check the squish?

 

[3000 FPS]

Did you check the squish?

That would certainly go to compression.

 

[Molly12345]

Did you check the squish?

No what should it be

 

[Molly12345]

There is something missing and is sounds to me like it is time to double check everything.
Putting a little fuel down the carb tells me a whole lot about what is going on.
If it tries to fire then I know right off that the spark is good and compression is good but fuel is not.
If it does not fire and he pulls the plug and it is wet then chances are no spark or bad compression.
Then time to put a compression gauge on it to see what it is. You cannot tell by feel on pulling the rope.

Did that very hard to pull over without decomp valve but registered 150 or better

 

[3000 FPS]

Molly have you put any fuel mix down the carb yet while holding it at wide open throttle and then pulling it over to see if it will try to start.