Husqvarna 550xp compression

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sambruin7

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I finally got a good compression tester and my new 550xp is reading low at only 130 psi. My well broken in 562xp reads 150 and my Chinese Redmax clone reads 155. I only have 3 tanks through the 550xp but isn't 130 low even for a new pro saw? I already took it back to the dealer because it was having some hot start issues and bogging and he did a full break down of the saw and said everything is fine. He also got 130psi and said that is within spec and told me it should go up after some more tank fulls of use.
 
If using synthetic oil it may not be seated yet.
What oil are you running?
 
I'm using a mixture of Amsoil and Royal Purple at approx. 45:1. So how many tank fulls will it take if that's the case? And how much can I expect the compression to go up from 130?
 
When I bought my last saw the dealer told me it can take up to 10 tanks on the synthetic oil for it to break in.

I do not know anything about what the compression should go up to.
 
I wouldn't expect it to come up very much if any at all. The piston is coming to the top of the hole couple hundred times a second at full power seating the rings seat in about as long is it took me to type this. For absolutely sure by the end of the first tank of fuel it's going to be about as good as it's going to get.....IMHO.

130psi seems pretty low for one of those. My oldest Husquvarna 55 has 150psi compression and minor damage to the P/C and looks HORRIBLE if you look into the exhaust port. I bought it with next to zero compression and heavy aluminum transfer, etc. Cleaned it up and it's got about a zillion hours on it since and keeps on getting it done and showing good compression.

Just had a 550XP brought into the shop that had about 60psi compression, was supposed to be bought new by the owner with low hours on it. I didn't even pull it down for inspection because I know what I'm going to find and the owner doesn't want to put a new OEM P/C on it.......Cliff
 
two things:

what's your altitude?

second, though i have no experience with the 550 i do have experience with the 575. i suspect that the 550 has similar strato ports. my 575 gets under 130psi at 6000 ft, but you have to wonder, when you look in the cylinder, how it does that with those extra ports. it's "effective stroke" is pretty short. when you put it in the wood you don't think about compression tests. it starts easy and runs really strong with a broad power band.
 
It cuts okay and sometimes has hot start issues. If it's hard to start I have to do the fast idle and rev it WOT for a few seconds and then it runs fine otherwise it'll bog down. I'm near sea level, just outside Los Angeles. My dealer told me the same thing that 130 is normal and that it takes several tanks for the rings to seal if I'm using synthetic oil. I took a look at the piston through the exhaust port and it looks clean, no scratches.
 
So what is the usual compression for a new 550xp? I'm sure my tester is accurate because my dealer got the same number and he's using the factory Husqvarna tester. And I can't trust him because he keeps telling me that 130 is within spec, that's all he'll tell me. If I ask him if he can test the other 550xp's he has and he said no or he doesn't have any which is bs. At first he tried to put it on me saying that I must've run it straight gas or bad gas or not enough oil.
 
So what is the usual compression for a new 550xp? I'm sure my tester is accurate because my dealer got the same number and he's using the factory Husqvarna tester. And I can't trust him because he keeps telling me that 130 is within spec, that's all he'll tell me. If I ask him if he can test the other 550xp's he has and he said no or he doesn't have any which is bs. At first he tried to put it on me saying that I must've run it straight gas or bad gas or not enough oil.
What is the compression on the saw now?
 
Just had a 550XP brought into the shop that had about 60psi compression, was supposed to be bought new by the owner with low hours on it. I didn't even pull it down for inspection because I know what I'm going to find and the owner doesn't want to put a new OEM P/C on it.......Cliff
Air leak?
 
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