Can't get Husqvarna to start

deadl0ck

Hi all,

I've got my Dad's Husqvarna Special 365 and I just can't get it to start.

There's a new spark plug in it and I've put fresh petrol / oil 50:1 mix in it.

I have an ignition tester (Something like this) so I know there is electricity going to the spark plug.

I've cleaned the air filter and checked that the fuel filter is not blocked also.

I've tried it with the chain brake both on and off.

If I recall correctly it was never easy started, but I just cannot get it started at all.

I have never once got it turn over for even a few seconds.....

Any ideas ??

Ten Pin

Inlet fuel gauze on the carburetor could be blocked.

TomOnBoard

Ten Pin wrote: »

Inlet fuel gauze on the carburetor could be blocked.

Also, if it had been left sitting for a while, the carb innards could be bunged up with varnishes from stale petrol..

I had a small Stihl that was a biach to start. I used to remove the air filter while starting it and let it run for a few minutes b4 putting it back on.

deadl0ck

Ten Pin wrote: »

Inlet fuel gauze on the carburetor could be blocked.

Is that difficult to access?

Do you mean the filter on service manual page 28 here ? (Page 30 on PDF page numbers)

Ten Pin

Couldn't open that link

It's called fuel inlet screen
Part no 501666101 on this pic
https://polr.partstree.com/v1/iplimage.php?ir=YToyOntzOjk6ImltYWdlUGF0aCI7czoyODoiYUhWemNYWmhjbTVoTHpBNFhETXhORnd3TURFeCI7czo3OiJvcHRpb25zIjthOjE6e3M6NToid2lkdGgiO2k6MTAwMDt9fQ

To access it needs taking off carburetor and opening it up. Easy enough but parts are small and the gaskets and diaphragm are delicate.

Before going to all that trouble, put a few drops of fuel in the cylinder through the spark plug opening, reinstall the plug and see if the engine kicks off at all. If it kicks off then you'll know it's a fuel problem. Then open up carburetor and check the fuel gauze/screen.

deadl0ck

Ten Pin wrote: »

It's called fuel inlet screen
Part no 501666101 on this pic
https://polr.partstree.com/v1/iplimage.php?ir=YToyOntzOjk6ImltYWdlUGF0aCI7czoyODoiYUhWemNYWmhjbTVoTHpBNFhETXhORnd3TURFeCI7czo3OiJvcHRpb25zIjthOjE6e3M6NToid2lkdGgiO2k6MTAwMDt9fQ

Yep - that's the bit I was talking about in the link you couldn't open

Ten Pin wrote: »

Before going to all that trouble, put a few drops of fuel in the cylinder through the spark plug opening, reinstall the plug and see if the engine kicks off at all. If it kicks off then you'll know it's a fuel problem. Then open up carburetor and check the fuel gauze/screen.

Actually - I put a spray of carb cleaner into where the spark plug goes and it didn't kick off either.
Maybe it is a spark / ignition problem.
It should have at least coughed for a second or 2 I would have thought...

What pressure reading do you get with a compression tester?

Nekarsulm

If you take a new spark plug and attach it to the it lead, then position it so that the end is resting on the cylinder head, you can pull the starter cord smoothly and watch if you have a spark at the plug.
Make sure the ignition switch is in the "on" position!


If you have a spark, screw in the plug and atfach the lead.
Now pull it over a half a dozen times, and take out the plug again, is it wet with fuel?

deadl0ck

JayZeus wrote: »

What pressure reading do you get with a compression tester?

I don't have a compression tester

deadl0ck

Nekarsulm wrote: »

If you take a new spark plug and attach it to the it lead, then position it so that the end is resting on the cylinder head, you can pull the starter cord smoothly and watch if you have a spark at the plug.
Make sure the ignition switch is in the "on" position!


If you have a spark, screw in the plug and atfach the lead.
Now pull it over a half a dozen times, and take out the plug again, is it wet with fuel?

Will give it a try later and report back - thanks

Ten Pin

Check the wires to the off switch

Not very scientific but take off pull cord assembly, turn flywheel while covering the plug hole with your thumb, there should be suction generated and released as the piston moves up and down.

deadl0ck

Ten Pin wrote: »

Couldn't open that link

It's called fuel inlet screen
Part no 501666101 on this pic
https://polr.partstree.com/v1/iplimage.php?ir=YToyOntzOjk6ImltYWdlUGF0aCI7czoyODoiYUhWemNYWmhjbTVoTHpBNFhETXhORnd3TURFeCI7czo3OiJvcHRpb25zIjthOjE6e3M6NToid2lkdGgiO2k6MTAwMDt9fQ

To access it needs taking off carburetor and opening it up. Easy enough but parts are small and the gaskets and diaphragm are delicate.

Before going to all that trouble, put a few drops of fuel in the cylinder through the spark plug opening, reinstall the plug and see if the engine kicks off at all. If it kicks off then you'll know it's a fuel problem. Then open up carburetor and check the fuel gauze/screen.

So - should it be down that far in the hole ?
Can I just remove it with a tweezers without taking the whole carb out ?

Also - there was a bit of sawdust in the square gauze filter also - I'll clean it off with carb cleaner and some compressed air...

Ten Pin

Yeah the fuel screen / gauze looks OK (normally, if it was blocked, the dirt would be clearly visible). Use a pin or needle around the edge of the gauze to prise it out. Although if it's clean, it probably doesn't need to be removed.

If you use compressed air, turn the pressure down low, the jets inside carburettors don't like high pressure blasts of air and the metering diaphragm on the other side of the carburetor won't like it either.

deadl0ck

Ten Pin wrote: »

Yeah the fuel screen / gauze looks OK (normally, if it was blocked, the dirt would be clearly visible). Use a pin or needle around the edge of the gauze to prise it out. Although if it's clean, it probably doesn't need to be removed.

If you use compressed air, turn the pressure down low, the jets inside carburettors don't like high pressure blasts of air and the metering diaphragm on the other side of the carburetor won't like it either.

I just cleaned off the dirt and refitted - still the same.
It's as if it's not getting a spark.
I bought a new generator lately and it wouldn't start - same symptoms - no matter how much I tried, it just wouldn't turn over.
Turned out the oil was a little low (even though I had checked and though it would be OK to make sure it ran) but there was a low oil switch so the ignition wasn't working - I'd get a single spark and nothing more, but once I topped up the oil it went on first pull - the symptoms on the saw look very similar - not once have I got it going for even 1 solid second.
I'll try checking the leads on the power switch next but I'll need a bit more time for that as they look like I'll need to do a good bit more dismantling to get at them....

deadl0ck

Got it to start - the switch was easy to remove actually - just prise out with a screwdriver.
Switch was fine but a fair bit of gunk on the connectors so I cleaned all with electrical contact cleaner.

Started on the 8th or 10th pull.

Funnily enough I had the spark ignition tester on it at the same time also - wonder if it make a better connection with the spark plug then the direct cable (although it did start without it after also).

It blew out a lot of white smoke for about 30 seconds from the exhaust.... then smoke started coming out all around the base of the cutting bar - it's full of crap and old saw dust so I'll clean it all up now.

I'm also going to add some Briggs and Staton Fuel Fit to the fuel mix to clean out the engine and also help with the starting....

Thanks for all the help ! Hopefully this is the last you'll hear of me