mattysmith440
New member
so. got my new cogshaft,went to install it and upon disassembly realized my chaincase was blown to pieces at the bottom bearing, obviously from the broken shaft rotating off balance. anyways long story short, and some $$$$ later she was rippin up the trails again. until on a couple evenings ago crossing the lake i started losing top end, so i thought oh no, another pull thru. but no, i wasnt that lucky! put 3 brand new plugs and same thing. tried my new belt, same thing! got a buddy to pull her over as i put my thumb over each cylinder, and low and behold the mag side has zero compression. but no piston residue on the spark plug. what could this be? hopefully a ring stuck?
all you guys complaining about no snow! i wish the 8 feet we have here would melt so i wouldnt have to keep fixing this f'n srx! but god love the beast when she screams after being down for a week!
any thoughts guys on what this would be? and if it just a ring stuck should i do all 3 piston and rings? she has 5000 miles and to my knowledge hasnt been apart.
thanks in advance guys
all you guys complaining about no snow! i wish the 8 feet we have here would melt so i wouldnt have to keep fixing this f'n srx! but god love the beast when she screams after being down for a week!
any thoughts guys on what this would be? and if it just a ring stuck should i do all 3 piston and rings? she has 5000 miles and to my knowledge hasnt been apart.
thanks in advance guys
motorhead327
VIP Member
Did you look down the plug hole to check the piston?
mattysmith440
New member
not yet, i slapped it on the lawn and havent looked at it, was too mad and was gonna wait till after xmas but i just cant look at it anymore, its building too much snow on it and should be driven! i am gonna go check right now
edunn69
VIP Member
No way to know without looking at it!
mattysmith440
New member
just checked and the piston looks perfect
mattysmith440
New member
but like i said, has absolutely no compression.
jaydaniels
VIP Member
If you have no compression something is going on. Hard to see much looking through the plug hole. You could take off the exhaust and try looking through the port to see if you have a stuck ring or damage on the exhaust side.
mattysmith440
New member
ya i have to do it the weekend. but if there was damage to the piston, the skidoo would make noise when running/wouldnt run. its does run, but just runs the same as it would if a plug was gone. no banging, clunking, no noise at all....and still moves as i drove it home half a mile. i HOPE its the ring
motorhead327
VIP Member
Oh man, Id be bugging out intill I knew. The lake crossing part is what scares me. Hopefully its something simple. I would perform a leak down test first!
mattysmith440
New member
it was a very small lake, wasnt wot for long at all. and to be honest i noticed earlier in the day the srx just didnt seem herself...so im thinkin maybe the ring was slowly fusing to the piston? how do i do a leakdown test?
with a gauge to do it ................... look like u toast a piston ......it doesnt do sound but performance and ilddling doesnt work good after u ruined a cylinder and piston ....u will need to find the problem or it will happend again ....carb or seal
mattysmith440
New member
i just really think if i toasted a piston, there would be some silver residue on my plug, but there wasnt the slightest bit. i guess ill see when i haul it apart
motorhead327
VIP Member
Here is alink in the tech section. http://www.totallyamaha.com/snowmob... down test/How to Cylinder Leak down test.htm
You can do a halfa$$ one by having a buddy blow air into the cylinder using a rubber tipped blowgun and listen to where the air is escaping. Just make to to regulate the air source first. You just wont know the percentage.
You can do a halfa$$ one by having a buddy blow air into the cylinder using a rubber tipped blowgun and listen to where the air is escaping. Just make to to regulate the air source first. You just wont know the percentage.
mattysmith440
New member
great link man thanks! will try that tomorrow!
jaydaniels
VIP Member
Probably a stuck ring. You might be able to see it looking through the exhuast port as many times that is the side they will stick. If the damage wasn't excessive and only to the piston side you may not see anything on your plug. If you don't see an issue then try the leakdown. You said you placed your thumb over the plug hole and had no compression. A compression tester would give you a more accurate reading on this. If your sure you have no or low compression it could only be an issue with piston and or ring or blown head gasket.
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ryan2001sx600r
New member
pull the head and take a look. It's going to have to come off anyway.
YAMMIEGOD3:16
Active member
YOU HONESTLY WERE RUNNING tHIS SLED WIDE OPEN IN 8 '' FT OF SNOW CROSS A LAKE ? 3:16 (yammie tony)
mattysmith440
New member
lol the lake is hard packed from a gazillion skidoos crossing it
bluemonster1
LIFE MEMBER ONLY ONCE!!!
that's more skidoos then people out there..so where are the Yamies then????