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Sounds like you've got your bases covered in the fuel dept. now with all the parts swapping and tests you've done. Could it be an ignition issue?
 
At this point my money is on a crank seal but I'm not one for throwing parts at a saw hoping for the best..... I'm the kind to know what’s wrong BEFORE I start fixing it, and this one is peacing me off.... I'm sure it's just because I had to quit in the middle that its grinding me so much but.......... :chainsaw:
 
Sounds like you've got your bases covered in the fuel dept. now with all the parts swapping and tests you've done. Could it be an ignition issue?

ignition module

Doesn't present as an ignition issue to me.... and I've seen a few bad saws, but hey, at this point I'm not ruling anything out.... that hasn't already been ruled out. :cheers:
 
Bent crankshaft...Passes vac/press test sitting still or while being turned over slowly, but at 13,000 rpm you get enough defelection to get an air leak on the clutch side...:cheers:
 
At this point my money is on a crank seal but I'm not one for throwing parts at a saw hoping for the best..... I'm the kind to know what’s wrong BEFORE I start fixing it, and this one is peacing me off.... I'm sure it's just because I had to quit in the middle that its grinding me so much but.......... :chainsaw:

Well if it held a good vacuum I'd doubt that. Did you turn the crank when you had a vac on it?
 
Well,

Working backward, by the process of elimination, we know the engine is good to go because it passed the P/V tests with flying colors.

So the problem MUST lie in one of the bolt ons.

1) Intake clamp tight.
I know you well enough to know that it is.

2) Intake boot pin hole
You would check, recheck and put a new one on to be sure.

3) Carb to intake seal.
Possible

4) Carb
Checks out good and replaced with a known good one. Should be okay.

5) Fuel line and filter.
Replaced with new

6) Possible leaks in elbow or fittings.
Have you tried pressurizing the tank to check for leaks?

What happens if you adjust the mixture?
Have you dumped and added new fuel?


Mike
 
Bent crankshaft...Passes vac/press test sitting still or while being turned over slowly, but at 13,000 rpm you get enough defelection to get an air leak on the clutch side...:cheers:

This is kinda where I am in my mind right now, but the crank "feels" tight. :cheers:
 
Most anything that leaks will not hold a vacuum very long, but it will not always lose a vacuum that small in a matter of a half hour. I would put a vacuum on it and leave it for the day if you can, won't pinpoint a leak but will let you know if you have one.
 
Last edited:
Well,

Working backward, by the process of elimination, we know the engine is good to go because it passed the P/V tests with flying colors.

So the problem MUST lie in one of the bolt ons.

1) Intake clamp tight.
I know you well enough to know that it is.
Yep

2) Intake boot pin hole
You would check, recheck and put a new one on to be sure.

:)

3) Carb to intake seal.
Possible
All good

4) Carb
Checks out good and replaced with a known good one. Should be okay.

;)

5) Fuel line and filter.
Replaced with new
;)

6) Possible leaks in elbow or fittings.
Have you tried pressurizing the tank to check for leaks?

Did not pressure entire fuel tank but lines are all good... a leak in the rest of the fuel tank would just emulate the tank vent.... would not affect the fuel mixture.

What happens if you adjust the mixture?

Just hits the wall at 12,500 for the 10 seconds and then screams lean.

Have you dumped and added new fuel?

Fuel is all good and has been changed to be sure. ;)


Mike


.
 
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