Hello
Hey there, I just got my first snowmobile, used 2007 phazer fx.
I've just been going through the sled checking things out and learning the ins and outs of it. Does anyone know what they are getting for Cylinder compression on their own sleds? I understand that these are high compression engines but the manual suggests the compression should be 206psi standard/230psi max/179psi min (thats testing at sea level and with a shot of oil down the holes)
even though its a high compression engine these figures seem excessive and high from what i know about engines. What is anyone else getting for compression in their phazers? does anyone actually see 200 or so psi?
Hey there, I just got my first snowmobile, used 2007 phazer fx.
I've just been going through the sled checking things out and learning the ins and outs of it. Does anyone know what they are getting for Cylinder compression on their own sleds? I understand that these are high compression engines but the manual suggests the compression should be 206psi standard/230psi max/179psi min (thats testing at sea level and with a shot of oil down the holes)
even though its a high compression engine these figures seem excessive and high from what i know about engines. What is anyone else getting for compression in their phazers? does anyone actually see 200 or so psi?
BigDogrx1
TY 4 Stroke Guru
Ya, seems a little high, my 03 RX1 is 175 on all 4 cylinders, that's with cold motor and no oil in cylinders,
Voda2000
TY 4 Stroke Junkie
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- 2007 Phazer GT 136"
These motors are pretty strong, especially if they are stock. Is there a reason you are checking the compression?
The reason I was testing it was only to check things out. I just bought it used with 4000km on it, that's all.
I tested it with engine warm and oil in the holes, I'm seeing 150psi in each which I would normally think is fine, then I looked at the manual and then i became concerned a little.
On the good side it does run nice and is not burning oil that I can tell. So I just wanted to bounce this off people who have experience with these phazers. Don't know if the concern is warranted.
I tested it with engine warm and oil in the holes, I'm seeing 150psi in each which I would normally think is fine, then I looked at the manual and then i became concerned a little.
On the good side it does run nice and is not burning oil that I can tell. So I just wanted to bounce this off people who have experience with these phazers. Don't know if the concern is warranted.
BigDogrx1
TY 4 Stroke Guru
Did you hold throttle wide open when cranking 5/6 turns?
That's correct I did that, (throttle wide open when cranking 5/6 turns)
thor452
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and the tester is a known good tester? any way to check that?
thor452
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I ask because i have two testers and one is only accurate up to 125 or so I know because the other one is dead on and have tested back to back with both and on a 2 smoke they are the same on the fourstroke the one reads way low.
As far as I know the tester is good , i've used it on other stuff and it seems correct .
One thought I had was I wonder if the starting decompression system affects the tests that you do?
One thought I had was I wonder if the starting decompression system affects the tests that you do?
Voda2000
TY 4 Stroke Junkie
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That's a good point. I'm not sure how that would affect it but there was an update for the 2007 models that changed the decompression to allow them to start easier. Might want to check the spec for the 2008 models and see if they were different.
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Looks like the same stats through the years of manuals.
Voda2000
TY 4 Stroke Junkie
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Darn, I thought it might be a simple answer.
I was just rereading the manual and I think you are suppose to test first without oil down the cylinder, then if the test is low add oil. If the number is the same for both the it's likely a valve out of adjustment. If it gets higher with oil then it's likely rings.
Did you test it without and with oil?
I was just rereading the manual and I think you are suppose to test first without oil down the cylinder, then if the test is low add oil. If the number is the same for both the it's likely a valve out of adjustment. If it gets higher with oil then it's likely rings.
Did you test it without and with oil?
blueironranger
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2009 Phazer MTX
150 does seem kinda low to me, If I had seen this last week when I changed my plugs I would have tested mine with my digital compression gauge to see what numbers mine has with 6000 miles on it. My Suzuki DF140 outboard hits 210-220 psi with only a 10:1 compression ratio. I see you said at WOT, 4 strokes NEED to be tested with the throttle open so you did good there.
