346 Timing problems.

[Mange]

I just got a 346 with ignition timing problems, I was wondering if anyone else has this experiance.
I suspect the flyweel is off a bit, but I will have a look now.

 

[Mange]

I cheched the timing and it seems OK.

Hmmmmmm.

 

[Mange]

Well I rouled out the timing and went on to the fuel system. Ignition is fine!
I got it to run after I put fresh fuel in it, it run's for a few sek and shuts down.
I can not find fuel in the carb after it stoped. The tank vent is OK and there gets to be enugh pressoure in the tank.
This carb was recently rebuild and the filter was missing in the carb.
I have begun to suspect there is little or no impulse to the membrane.
Either that or a leak in the rubber between carb and cylinder (it was replacedwith a new + piston and ring when carb was redone).

 

[Lawn Masters]

I suspect that myself in such a case. check it out and see. I assume this is a Husky 346XP and not an Echo 346 right?

 

[Mange]

No Echo here.

You would suspect timing if you had it I promice.
I did not act as a common air leak.
I was told it got wet spark plug, but I did not get it wet.
There could be more than one problem too.........

 

[Lawn Masters]

Could be. maybe we should swap problem saws for fun LOL, across the pond saw service

 

[Mange]

I can not find any viseble foults on this saw, but it will not pump fuel.
Tomorrow I get a new rubber and will replace the entire carb if it is not the rubber.

 

[Kenskip1]

Mange,
How about replacing the gas filter? Possibly a kinked gas line? How is the compression? How old is the saw? It could be that some water may have got into the petrol tank.If this is the case the engine will not draw the water seeing that water is heavier than gasoline. Ken

 

[HiOctane]

Did you check if the short impulse line is not cut or off from the impulse?Also,you said the engine has been rebuilt ,maybe they put the base gasket backwards,then the impluse is blocked.Other things should be air leak by intake boot or seals.

 

[Mange]

I ordered a new intake, and will try another carb on mon. till then it will have to wait.

As i said Cylinder and piston is new, it is pressure tested at the dealer, they could not find the source of problem and suspected timing to be off.
I got the saw and checked the timing as they requested and there was no problem with ignition at all, as i can see/understand.
The fuel system is another matter. There is no impulse to the membrane to pump, therefor there is no fuel ( with exception of that that gets pushed in by tank pressure. I checked tank vent and the carb is rebuild at the same time top was replaced.

There is no obvious fault and no parts appear to be busted, it holds up to pressure tests, and comp is very well.

This is a tuff one since the ones that gave up has more than 35 years in the business.

Problem is in fuelsystem, and it affects the impulse, a option would be crap in the carb that will not come out bu standard methods, that is the reason for replacing carb. This is where I put my 10 cent's but we will see, I have been wrong before.

 

[Lawn Masters]

If that doesnt fix it, look at the base gasket, it may be blocking the impulse hole on the cylinder. its a possiblity. perhaps the impulse line is blocked by carbon or something too, I really am out of ideas on this one.

 

[trimmmed]

Check your gaskets and see if anything is blocked off.

 

[ozflea]

I f all these ideas don't help just shoot it and throw it's ugly carcass in the bin.

Mc Bob.

 

[Mange]

This is done Trimmed and OSD, I will continue the search monday.

 

[Mange]

If all else fail, Bob I will use this as a rat trap at the addict

 

[SWE#Kipp]

How is the 346 coming out, have you got it running yet ??

/Kristoffer

 

[Mange]

Nah I am busy with other stuff right now (Kristianstads dagarna ).
I will be at it again tomorrow.

 

[Mange]

Well, i put in a tested fuktional carb, a seckond new impulse line new rubber, still the same!!!

Checked the fuel line and changed it + filter just in case, still the same.

They do not make them like they used to

Ignition
Good spark at right time, but run's lean

 

[Mange]

I needed something fun so i put together a 77 instead before I went inside, runs like a dream.
New handle, a change of gas and it was running on 4 pull's.
As usual the naiburs thought my house was on fire, the smoke was bad there for a minut.

 

[SWE#Kipp]

haha