Low compression on my new Stihl MS362

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That’s why I don’t like giving compression #’s on tickets. Only when asked.
Gauges can fail and give a false reading at any time. Or different gauges used on test. I bet we all use a different brand gauge.
It could be off by only 30 psi.
That’s enough to say oh shît my engines toast.
If in doubt pull the muffler.
I calibrate mine against 2 other sources if they are all within 1 lb you can bet its right!
 
Stop at the saw shop on the way home yesterday, talked to the tech he has really hadn't time to look at it since I dropped it off late Friday after work. He did run a cold compression test and got 120 lbs. It was raining side ways yesterday and he didn't really want to go out and test the saw in that. He really was questioning me why the other shop just sent me on my way, they should have looked in to it more. He said he let me know what they find. The saw does have another .1 hours on it since the last two test.
 
Stop at the saw shop on the way home yesterday, talked to the tech he has really hadn't time to look at it since I dropped it off late Friday after work. He did run a cold compression test and got 120 lbs. It was raining side ways yesterday and he didn't really want to go out and test the saw in that. He really was questioning me why the other shop just sent me on my way, they should have looked in to it more. He said he let me know what they find. The saw does have another .1 hours on it since the last two test.
Even 100 hrs the comp should be good!
 
I just pulled a new 362 off the shelf and it’s got 150psi. Are they using the right 10mm gauge?

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I just pulled a new 362 off the shelf and it’s got 150psi. Are they using the right 10mm gauge?
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I'm not sure if they are using a 10mm gauge, My gauge has about 10" rubber hose from the fitting to the gauge. The 1st shop had a setup similar to what I have. Not sure what the 2nd shop has.
 
It would just be broken in, rings set at 100 hours, when they get 1500 hours on them they might need rings, at 2000 they require a new piston and a good checkup.

The guy at the shop said it Normal break-in should be 5 to 6 tanks, I bet my saw doesn't have 1/3 tank...maybe 1/2 ran thru it. I'm just sick about this whole thing...bit concern after reading all the post from you guys. Especially X 66's test...doesn't look good if they don't warranty my saw. X 66's new saw off the shelf ( a saw that's never ran) and he's getting 150PSI cold, both I and 1st shop hot compression test 110 psi, 2nd shop cold 120 psi on my new saw. If X 66's getting 150psi... its not engineering in the cylinder transfers, it just plain a bad saw. The guy last night said he was going to pull a new saw off his shelve too and test it...but he said a new saw should never be <135 psi. He was positive about that. I talked to him about my oiler too...he said that could void the warranty technically. He's said he'd call me let me know...today nice day so hope to hear from him soon.
 
I always see 150-155 on a new 261 and 362. This is a off the shelf 261 with a different gauge than my 362 test. The throttle needs to be wot
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I always see 150-155 on a new 261 and 362. This is a off the shelf 261 with a different gauge than my 362 test. The throttle needs to be wot
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Boy thanks X 66 I really appreciate your time. I ran my test WOT too, the 1st shop did not thou. I'm convinced I have lemon.
 
I aint! did you pull the muffler yet or cross check your gauge! Waiting on some Still shop may not get you anywhere! That part about the oil pump!!!!!

I'm sorry Lone Wolf ...the shop has my saw and I'm not going take it from them if they are willing to help me! If this shop is willing to address this with Stihl on a warranty issue why would I go get my saw? The shop I bought the saw from isn't. This shop that has my saw now... didn't make a thing on that sell and is willing to help, I'm going to wait! If I get this saw back and no one willing to help...yes I'm going to run a camera inside the cylinder and do a squish measurement also. Then write a heck of letter to Stihl before I take that saw a part. This whole thing has been on my mind and if Stihl won't address this I going to be pretty upset. In fact if the saw has no warranty and I'm on my own... and the cylinder looks good. I think the best thing is to lap the cylinder bring the compression up. This whole situation just is very upsetting...trust me I want to know what the issue is with this saw and if the warranty on Stihl is any good. Its be pretty hard to dispute anything I did that would effect that saw compression. Its the shops fuel, they tuned it and I brought it to them before I cut any wood because it flooded easy, they said it was find. I cut two trees that night, ran A compression test and took it in the next day (Friday noon), Friday night I stop at a different shop they took my saw as a warranty repair. I had hour meter on the saw before I ever used it (.3 hours), the 1st shop put .1 hours on for .4 hour total run time. The saw just didn't seem to have much power when I ran it. The 2nd shop wants to run it before sending it for warranty...I'm not sure why but I'm not going to argue.
 
OP what compression tester do you have and what readings are you getting from other saws? Do you know the tester to give higher readings or is it new?

I'm not sure what the brand my compression tester is....but I trust it. I have two 034 I've been working on and ran compression on both saw in last few months. Tell you what I'll grab my 034av and run another test tonight, take picture...it should be >150psi. The 034 super is torn down blocked off for pressure/vacuum test so can't do that one. If I have time I'll grab my MS460 and run one on that saw too. I'll place a bet with you my gauge is good...fair.
 
I'm not sure what the brand my compression tester is....but I trust it. I have two 034 I've been working on and ran compression on both saw in last few months. Tell you what I'll grab my 034av and run another test tonight, take picture...it should be >150psi. The 034 super is torn down blocked off for pressure/vacuum test so can't do that one. If I have time I'll grab my MS460 and run one on that saw too. I'll place a bet with you my gauge is good...fair.

OK ran a check on my compression gauge it's US made... just to put all questions aside about my ability or my equipment. My 034av was a landing saw and pre 1993 so it's old. My MS460 I've had a while 6 or 7 years maybe older, I don't remember but I bought it new. I would say both of these saws are fine as is my equipment. The new MS362 is very low and the readings I took are correct. The readings the 1st shop took are correct I was standing next to them when they took it, I saw with my own eye. Sorry I'm just upset about this darn saw the more I think about putting together a go to saw and have something I can't use. No word from the shop that has my saw today.
 

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OK ran a check on my compression gauge it's US made... just to put all questions aside about my ability or my equipment. My 034av was a landing saw and pre 1993 so it's old. My MS460 I've had a while 6 or 7 years maybe older, I don't remember but I bought it new. I would say both of these saws are fine as is my equipment. The new MS362 is very low and the readings I took are correct. The readings the 1st shop took are correct I was standing next to them when they took it, I saw with my own eye. Sorry I'm just upset about this darn saw the more I think about putting together a go to saw and have something I can't use. No word from the shop that has my saw today.
Well we eliminated that thanks. I guess you know its the saw now. OK keep us in the loop ,I know you will.
 
Whatever the problem is I can’t see why it wouldn’t be warranty. Just stay on the dealer to get it done.
I had a saw come in one time that had low compression and was 15 min old. Pulled the muffler piston looked perfect.
But failed a leak down test bad.
After a teardown a snagged ring was found. Turned out the Piston didn’t have a pin in the ring land.

This is a 1 1/2 year old ms391. It was registered to a tree service so it’s way out of warranty.
Stihl shipped a new piston and cylinder to fix it. That problem was supposed to be fixed so they made good on it. Plus I sent them the vid.
 
The guy at the shop said it Normal break-in should be 5 to 6 tanks, I bet my saw doesn't have 1/3 tank...maybe 1/2 ran thru it. I'm just sick about this whole thing...bit concern after reading all the post from you guys. Especially X 66's test...doesn't look good if they don't warranty my saw. X 66's new saw off the shelf ( a saw that's never ran) and he's getting 150PSI cold, both I and 1st shop hot compression test 110 psi, 2nd shop cold 120 psi on my new saw. If X 66's getting 150psi... its not engineering in the cylinder transfers, it just plain a bad saw. The guy last night said he was going to pull a new saw off his shelve too and test it...but he said a new saw should never be <135 psi. He was positive about that. I talked to him about my oiler too...he said that could void the warranty technically. He's said he'd call me let me know...today nice day so hope to hear from him soon.
It really takes about 10 - 12 tanks before they reach full comp and get as strong as they can, they will have 130 - 135 comp cold right from the start but if oil is present in the cylinder, added or just from assembly then the comp will be much higher. Run the saw, oil gets burned off and the comp will drop until the engine gets run enough to break in and the comp will come back up.
The warranty thing is all about the dealer, if they can find a way/anything changed from basically stock they can at their discretion turn down the warranty. Any part that required a screw to be removed actually voids the warranty if they want to push it. I mentioned earlier a chap drilling extra holes in his airfilter cover, turned down for warranty so I went and bought a new cover through a different shop and replaced the drilled out one. Took the saw in to a different shop that knew me well, they got that saw fixed under warranty with no problem because they knew me and wanted to get the saw fixed. You have now found a shop/dealer that wants to help, let them, don`t interfere yet but let them handle it. If they find the oil pump, not all that likely then deal with that when it happens, just leave the saw there and see what they come up with.
 
By allowing the second Dealer to put the saw through their own tests, you’re demonstrating your character as a customer, while allowing him to demonstrate his character as a businessman. You show him you’re not a “nightmare” customer and he shows you his Shop is worth the trip.
I think you’re doing fine...
 
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