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Discussion Starter #1
I was riding my sled yesterday with no issues at all ..
end of day, my sled crapped out...
- I hit the gas full throttle ... got to about 100 km/h
- all of a sudden the sled stalled and came to a complete stop.

- I tried starting it again .. no go ...
- I tried pull starting it .. seems like the motor is seized. I broke the recoil.
Anyways, I was taking the belt off to have it towed back ..
- I guess I free'd up the motor from the crank by doing so .. Motor turns over now, starts but seems like its running on one cylinder ..

Any Ideas on where to start troubleshooting ???
 

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Discussion Starter #3
Thanks RJ ... i was hoping it was something small .. damnit ..
Anyways, do you know where I can get a manual .. I need to fix this thing ..
Any suggestions on how to change a piston ?
 

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When you rebuild be sure to check your fuel pressure both low and high your engine is prone to failure of the low pressure fuel pump causing the engine to lean out and melt down.
 

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twins rule!
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the proper way to fix a skidoo, is to replace it with a polaris or artic cat. sorry dude I feel your pain,thought a joke might help.
 

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Discussion Starter #10
Lol .. thanks Farmaloose .. this is my first skidoo .. I still have my Polaris rmk 800 ...
Anyways, I did a compression test .. 45 lbs on one cylinder ...

So basically i have to replace a piston and the gaskets ... Anything else ??
Why would this fail ??
Oil Pump bad ?
How can I check to see if the oil pump is ok ?
 

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Like I said in my first response your engine is very prone to meltdown due to fuel pressure problems you have a low and high pressure fuel pump and it is very common to have a problem with the low pressure pump causing a lean burndown. highly unlikely that you have an issue with the oil pump. I would suggest a little searching over at Dootalk in the machz section you will find lots of good reading on the cause of this failure and many good sugestions to keep it from happening again. just a start would be adding fuel pressure gauges and an exhaust temp gauge with preset warnings so you can see if you start to loose fuel pressure or if you start to go lean and raise exhaust temps.

Your sled should always maintain 58-62 psi of fuel pressure on the high pressure side if your low pressure fuel pump starts to have issues you will see dramatic drops on the high pressure side it will drop 25-30psi

I would also suggest getting a manual and doing a leakdown test before you dissassemble the engine to see if your crank seals are leaking they can also be a cause of a meltdown especially if the cylinder you melted down is the pto side.



Owning a MachZ is like having a high maintenance girlfriend if you knew the true cost of keeping it up going in you would never do it!
 

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I'd take one of those MAch Z's in a minute. Baddest sled Doo ever made IMO.
No argument there I have been thinking of picking one up as a second sled for when we get on the lake and such but there are some things that need to be done to give them some reliability.
 

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Discussion Starter #15
$1600 dollars later, I managed to get her going ! I'm scared its going to happen again.
Also, i bought a Silencer but there is not hole for the EGT, like in the stock muffler. Buddy says just to tie it up somewhere .... Do you think this is correct ?
 

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05 mach z 1000 piston melt down

hi guys I just had my right side piston go down and it wasn't because of fuel pressure because I have always had a pressure gauge and it never dropped n pressure, so now iam really dumfounded why this happened. I worst of it all i just it rebuilt the winter before last I prob has 1000 miles on it. I Did a ton of research to keep this from happing and all the updates but ended up being a waste of time. I guess it is the nature of the beast
 

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NH, ME and VT Rider
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My buddy just blew the engine in his Mach Z, I was behind him and all of a sudden there was a ton of smoke. There was antifreeze and oil pissing out. The sled only had 2800 miles on it. We had to tow it 15 miles to the nearest road.
 
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