Husqvarna 545 dies when tilted either side or forward, but ONLY when hot

[1d10t]

5 hours ago, Muddy42 said:

I stand what I said before something doesn't seem right here or different parts have been used.  Regarding fuel lines they normally perish long before any damage.  Were the fuel lines replaced with generic pipe of a wider diameter maybe?

 

Did the extra insulation fix the dying issue?  

I think cylinder is Mahle which should be the original OEM part. If different parts were used, then it was funny dealer business, because they were the only ones to touch the saw except my dad and I. Was told that piston was replaced in first 2 weeks after new, but warranty was declined due to bad fuel apparently (which I still don't believe was the cause). Originally I thought that whole cylinder was replaced. Everything else should be the original except the stuff I mentioned (filters, lines).

Haven't had the chance to try out the saw after the fix yet as we have some bad weather now, hoping for a test run in a week or so.

I was hoping to take a look at coil-carb wires too, but I can't find out where they go, they're not in the same place as mk2 and they're not between fuel tank and crankcase, seems they are INSIDE the crankcase???

I read somewhere that they were prone to grounding on the crankcase and in future revisions were modified with extra insulation. Since the saw was bought in early 2014, I think it's one of the first batches made so probably had some issues. But i'm not sure when they were first made.

[1d10t]

As for the fuel lines, the one most damaged was fuel return line which I think was rubbing on throttle cable, that could've been due to improper installation or maybe it slipped out of clips some day.

But the spark plug wire was definitely damaged by being squished between top cover and cylinder. I cut a part of the top fin off now so it shouldn't rub anymore.

[adw]

It is very important that the spring on the red stop switch is under the choke shaft when re assembling the carb to the machine, if the wrong side it affects the movement of the switch, the machine will have a home produced cylinder so will not be Mahle, the cables from the ignition unit connect to the auto tune unit with a white block connector, but there is a single separate wire which is the ground wire for the auto tune unit, this wire runs under the induction tube and is secured by one of the carb floor screws, it is very important this wire is well secured or this will affect the running, I was a little concerned to see what looks like a 14mm plug fitted, heaven knows how that affects the combustion chamber area.

[1d10t]

I will recheck the cylinder again to see if there are any markings, but I THINK it was mahle. The ground wire is secured, I checked it when vac testing about 2 weeks ago. The switch is assembled fine too and works as intended, choke, high idle and removes high idle when throttle is pressed. I'll talk to my dad about the cylinder again, he assured me that only piston was changed at the dealer, the only other cylinder was the amazon one which I now have in the basement and was fitted couple months ago (and got a piston ring caught in one of the very nicely cast ports...).

As for the spark plug, it should be mostly the same, no? it is the same length as the original. it was either that or a new oem cylinder which is worth more than the saw currently and the stalling issue will remain since it was the same on both cylinders. 
The saw actually runs and starts fine (1 pull from cold today), the only issue is stalling whewn hot.

As I said, I'll see if spark plug insulation helped when I can get into the woods again.

[1d10t]

I was only able to cut about three 50cm stumps and some smaller (10-15cm) logs before dark, but it seems to be working fine now, there is no stalling at all and I was rotating it every possible way every minute or so.

Unless there really is an oil tank leak and it doesn't happen with full tank. Will see once I have more (and bigger) wood to cut, but then I'll probably be using a 365 for that.

[1d10t]

Had some more trees to cut today and the problem reappeared when the saw was decently hot. Didn't even need to turn it to the side, it just cuts out instantly sometimes (for example when putting it into wood). Won't be putting anymore money into it, it will just be a secondary saw for occasional limbing.

Almost looks like compression is so bad that it just doesn't have enough when hot.

When measured (though my compression tester is a budget one) it was only 85 psi, compared to new 365 xt's 120 psi (assuming tester shows like 20-30 psi lower than it should).

[Mark_Skyland]

Poor compression usually shows by lacking in power, hard to start when warm, nearly impossible to start even and it wont tick over.

If its cutting out as though its been switched off then I think that you still have an electrical fault somewhere.

Does it start up straight away, tick over and still has plenty of power?

 

[Stubby]

4 hours ago, 1d10t said:

Had some more trees to cut today and the problem reappeared when the saw was decently hot. Didn't even need to turn it to the side, it just cuts out instantly sometimes (for example when putting it into wood). Won't be putting anymore money into it, it will just be a secondary saw for occasional limbing.

Almost looks like compression is so bad that it just doesn't have enough when hot.

When measured (though my compression tester is a budget one) it was only 85 psi, compared to new 365 xt's 120 psi (assuming tester shows like 20-30 psi lower than it should).

I had that with my very early 560 . ( on e of the first )  Fittec a hotter pug , had a new carb fitted under warranty band up dated the soft ware . Been fine ever since . ( also ported by petemate  ) 

[1d10t]

1 hour ago, Mark_Skyland said:

Poor compression usually shows by lacking in power, hard to start when warm, nearly impossible to start even and it wont tick over.

If its cutting out as though its been switched off then I think that you still have an electrical fault somewhere.

Does it start up straight away, tick over and still has plenty of power?

 

Starts back instantly yes. If it's coil or carb, I can't do anything either, both are way too expensive to buy for this saw, no point spending 200 euros on something that might or might not fix the issue. If it was a non autotune saw, I could just swap over a different coil to test, but here... If I understand it right, it needs to be fitted and coded by the dealer, I can't even find any replacement coil online.

[1d10t]

Or I could try to check carb wires too if I can find them, but those shouldn't be damaged since they're hidden.