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New 390 xp problem


Bayhales
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Started it earlier with no decomp with ease.

 

So is it normal for a brand new bigger saw to not like the decomp valve open when starting from cold? All I'm thinking is that its abit odd how its brand new and the operators manual would tell you to use the decomp..

 

Thanks for the reply's. Still not sure whether to send it back though.:blushing:

 

The decomp basically lowers compression for easier starting but to get a saw to fire, you need at least 130psi compression.

 

On a new saw, the piston and ring won't have bedded in to the shape of each other so a brand new engine will have less compression than a used one with a few hours use.

 

So in short, a brand new engine may be a bit sensitive to not starting on decomp when brand new. It will be a different story when a few months are over and compression is up 20psi!

 

Some saws are worse than others 365 Huskys are a bit prone to this!

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The decomp basically lowers compression for easier starting but to get a saw to fire, you need at least 130psi compression.

 

On a new saw, the piston and ring won't have bedded in to the shape of each other so a brand new engine will have less compression than a used one with a few hours use.

 

So in short, a brand new engine may be a bit sensitive to not starting on decomp when brand new. It will be a different story when a few months are over and compression is up 20psi!

 

Some saws are worse than others 365 Huskys are a bit prone to this!

 

Got it! Cheers.

 

Just one more thing. What do you recon about the chain creep? is this normal for a higher powered saw when idling? nitpicking over :001_tongue:

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Got it! Cheers.

 

Just one more thing. What do you recon about the chain creep? is this normal for a higher powered saw when idling? nitpicking over :001_tongue:

 

No saw should spin or creep the chain on idle, it is a sign that either the clutch springs are shot, the clutch system is dirty or there is binding between the crankshaft and clutch.

 

In this case, it may just be that the new parts are bedding down as they are new but they should be OK within a fewminutes of use. SOmetimes heavy grease can cause drag that is enough to do this or a very loose chain but if not correct - back to the dealer.

 

The only thing I would do is to rev it and slap the brake on a few times and see if that clears it.

 

On a normal idle, does applying the brake stop the engine, if not, let the saw idle for a few minutes with the brake on. Both this and the above should sort the issue out unless there are more indepth issues involved.

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I recently bought a 395 picked it up on a Saturday evening, Sunday it would not bloody start, they were shut Monday so Tuesday afternoon after work I took it out of the workshop ready to take it back, thought I'd try it and with a few pulls it went!

It's ok now. Maybe it's an auto tune thing.

 

 

Only 5-series huskies have AT, you flooded it.

 

To the op, don't start with the decomp, the saw doesn't need it (unless you break the rewind spring/side casing and don't replace it). Assuming you have the piped muffler, firing is literally just a pop, it's not very loud, I find it easier to start the saw without ear defenders until you're familiar with the saw.

In regards to the chain creep, is the chain tension correct, and is the idle speed correct? Does the saw pick up straight away with the throttle or lag?

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On my little saw the oil pump drive was stuck on the crank causing the chain to run and it was enough to stall the saw when you put the brake on. I took the clutch off, pulled the drive and rubbed the inside with emery then washed it out and greased it and it is fine now.

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