Chainsaw issue
 

I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good
indicator that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it
will start again.

When it is revving it cuts fine with no loss of power.

I have cleaned air filter, checked plug gap, used new fuel, general
clean to get rid of any oil or wood chip build up.

Any tips ?

Chainsaw issue
 

rick wrote:
I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good
indicator that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it
will start again.

When it is revving it cuts fine with no loss of power.

I have cleaned air filter, checked plug gap, used new fuel, general
clean to get rid of any oil or wood chip build up.

Any tips ?


Chain jamming or chain brake fault? I presume youre using the correct
oil/fuel mix and the engine isnt tightening up? How about the chain oiler?
Is it consuming oil at the expected rate?

Tim

--
Please don't feed the trolls

Chainsaw issue
 

On Saturday, 12 January 2019 14:05:07 UTC, rick wrote:
I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good
indicator that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it
will start again.

When it is revving it cuts fine with no loss of power.

I have cleaned air filter, checked plug gap, used new fuel, general
clean to get rid of any oil or wood chip build up.

Any tips ?

Check fuel tank/filter for debris/chippings blocking outlet pipe.

Chainsaw issue
 

On 12/01/2019 15:06, harry wrote:


Check fuel tank/filter for debris/chippings blocking outlet pipe.



Any idea how to get to that ?

I just took plug out again .. nice biscuit colour so all seems well there.
Used compressed air to blow through carburettor breather pipe back to
tank - all clear.

Carburettor is a Zama W26 .... not sure if it has a diaphragm or not, if
so I suppose that could be suspect.

Chainsaw issue
 

On Saturday, 12 January 2019 15:32:20 UTC, rick wrote:
On 12/01/2019 15:06, harry wrote:


Check fuel tank/filter for debris/chippings blocking outlet pipe.



Any idea how to get to that ?

I just took plug out again .. nice biscuit colour so all seems well there.
Used compressed air to blow through carburettor breather pipe back to
tank - all clear.

Carburettor is a Zama W26 .... not sure if it has a diaphragm or not, if
so I suppose that could be suspect.

With many chainsaws, the "carburetor" is in fact a fuel pump worked off crankcase vacuum. So it will work in all positions.

Chainsaw issue
 

On 12/01/2019 14:31, Tim+ wrote:
rick wrote:
I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good
indicator that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it
will start again.

When it is revving it cuts fine with no loss of power.

I have cleaned air filter, checked plug gap, used new fuel, general
clean to get rid of any oil or wood chip build up.

Any tips ?


Chain jamming or chain brake fault? I presume youre using the correct
oil/fuel mix and the engine isnt tightening up? How about the chain oiler?
Is it consuming oil at the expected rate?

Tim

Possibly although my money would be on Chris and Harry's suggestions of
a fuel blockage.

Chainsaw issue
 

rick posted
I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good
indicator that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it
will start again.

When it is revving it cuts fine with no loss of power.

I have cleaned air filter, checked plug gap, used new fuel, general
clean to get rid of any oil or wood chip build up.

Very common problem with small two-stroke engines. Usually turns out to
be gunk in one of the carburettor passages or apertures.

--
Evremonde

Chainsaw issue
 

On 12/01/2019 14:04, rick wrote: I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good
indicator that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it
will start again.

When it is revving it cuts fine with no loss of power.
If you quickly loosen the fuel cap after it has died does it suck air?
Similarly will it run for longer if the tank is half full rather than
full?
I have cleaned air filter, checked plug gap, used new fuel, general
clean to get rid of any oil or wood chip build up.

Always a good idea to have a new plug available, I have one here that
runs for 20 seconds then stops, it had me fooled for a long time as I
thought the fault was in the coil.

Apart from vacuum forming in the tank there are a couple of things:

1 cracked or leaky impulse line, this is the bit that communicates from
the crank case to the diaphragm pump in the carb, some say these
deteriorate due to increased ethanol in fuel.

2 blocked filter in gallery between pump and needle valve in carb, this
is a metal mesh. Occasionally this can also trap a blob of water which
leads to erratic behaviour.

AJH

Chainsaw issue
 

On 12/01/2019 14:04, rick wrote:
I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good
indicator that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it
will start again.

When it is revving it cuts fine with no loss of power.

I have cleaned air filter, checked plug gap, used new fuel, general
clean to get rid of any oil or wood chip build up.

Any tips ?
That would be the symptom if the fuel tank air vent was blocked.

Chainsaw issue
 

rick Wrote in message:
I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good
indicator that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it
will start again.

When it is revving it cuts fine with no loss of power.

I have cleaned air filter, checked plug gap, used new fuel, general
clean to get rid of any oil or wood chip build up.

Any tips ?


Fuel issue
--
Jim K


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

Chainsaw issue
 

"rick" wrote in message
...
On 12/01/2019 15:06, harry wrote:


Check fuel tank/filter for debris/chippings blocking outlet pipe.



Any idea how to get to that ?

I just took plug out again .. nice biscuit colour so all seems well there.
Used compressed air to blow through carburettor breather pipe back to
tank - all clear.

Carburettor is a Zama W26 .... not sure if it has a diaphragm or not, if
so I suppose that could be suspect.


just had the same thing on a leaf blower
new diaphragm fixed it

-

Chainsaw issue
 

"rick" wrote in message
...
I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good indicator
that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it will
start again.

When it is revving it cuts fine with no loss of power.

I have cleaned air filter, checked plug gap, used new fuel, general clean
to get rid of any oil or wood chip build up.

Any tips ?

Sounds like you have something in the carby that moves
around and blocks the jet when you get the loss of power.

Chainsaw issue
 

On 12/01/2019 16:56, Jim K.. wrote:



Need a special tool to remove H & L adjustment screws (mixture) as they
are splined - just ordered one ..... I'll remove and see if any gunk in
them.

Chainsaw issue
 

Tim+ pretended :
newshound Wrote in message:
On 12/01/2019 14:31, Tim+ wrote:
rick wrote:
I have a McCulloch 360T
Starts fine .. either hot or cold ... which in itself is a good
indicator that many things are Ok with the saw.

In use ... be cutting fine then revs will die, then get to a point with
chain out of the wood .... tickover is fine, but when I try to rev it
picks up, but after about 20-30% of power then dies off ... often to a
stall.
It can often take 10 or more attempts before it will get to point that
revs will open up .. then it cuts fine ... but a few minutes later it
will start again.

When it is revving it cuts fine with no loss of power.

I have cleaned air filter, checked plug gap, used new fuel, general
clean to get rid of any oil or wood chip build up.

Any tips ?


Chain jamming or chain brake fault? I presume you?re using the correct
oil/fuel mix and the engine isn?t tightening up? How about the chain oiler?
Is it consuming oil at the expected rate?

Tim

Possibly although my money would be on Chris and Harry's suggestions of
a fuel blockage.


Inclined to agree. ;-)

Tim

I agree - it sounds as if it is running out of fuel, despite fuel in
tank. Check the fuel pickup pipe in the tank - if should be flexible
and have a weight in the end, so gravity keeps it in the fuel.