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Discussion Starter #41
I agree with the Coolhand and TheBearAk. Something is just not right about something. I've seen those crankshafts go out of phase, but that takes some serious doing. The machines I've seen do that usually would start and run, but either had a really bad unusual vibration, a steady missfire on one cylinder or both. Check everything out very carefully. Grab the connecting rods and look for up and down play. Look for damaged crank seals, or slipped gaskets. Remove the engine from the sled when ya do this. Holes or cracks in crankcase are bad. Here is the $1,000,000 question. Why was the original piston damaged? What was the cause of that? Take and send lots of fun photos if you like. I'm really curious about this one. I kinda thought the variance in cranking compression could be due to the fact she hasn't ran yet, but that may very well be a clue as to other problems.
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I will do that! Thank all of you for all the advice! I appreciate it. I’m not sure when I will be able to tear it down and afford new parts but I will keep everyone updated! Thank you again
 

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John from Washington
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I feel your pain....I did a top-end rebuild on a Summit 800: New fuel lines, new fuel pump, new pickup line and it would not start!

I installed primer system and implemented small change in my starting procedure. It now starts with 2 pumps and 2 pulls, I'm not complaining

I took it to the shop before the rebuild and they got it started. The mechanic told me I needed to open the throttle "just a bit" while starting...this beast has 800CC motor so unless you are a Navy Seal, it is pretty hard to start with one hand and use the other to "open the throttle just a bit". I discovered that the shaft of a Sears stubby phillips would hold the throttle open just enough to let air pass over the jets, while I pulled with both hands. Eventually I replaced the phillips with "pin on ring" to make it easier to pull out when this beast roars to life. The "pin on ring" is attached on to the handlebar so that I don't dig through a toolbar every time that I start it.

Clear as mud? IM me and I'll send you picture of what I am talking about.
 

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lol, I usually end up using a glove to hold the throttle open and just be really quick to pull it out just in case.

The 125-149-150 did puzzle me, but figured the first one tested normal and the other two had a bit of help, maybe from extra oil or something. I would bet that if he started it, let it get up to temp, then checked compression it would be more like 125-125-125.
 

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Hello, I just rebuilt the top end of my sled due to it over heating and seizing up. Now that it’s all back together I have pulled and pulled it trying to start it and I get nowhere. I have gas, spark and compression but it just will not start. The choke switch is broken so I cannot choke the engine while attempting to start. I have tried everything any advice would be greatly appreciated.
Way to go! I rebuilt the top end this summer of my 96 500. You have to get the choke fixed. Mine will not start without choke. The switches are sold at Polaris dealers or on-line so it should be a simple fix.
 

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Have you checked the reeds ? If you put gas down spark plug hole and it didnt run sounds like stator or firing problem . i have never seen a two stroke that if it had gas down the hole it wouldnt run for a second if timing was correct.
 

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You said that you have drained the crankcase several times. If you are you getting more than a teaspoon of fuel out then you're flooding and that's why it won't start and probably showing higher compression on those two cylinders. Just rebuilt a 95 over the weekend and it was doing the same thing until we swapped out needle and seats.
You can choke the engine if you have someone hold their palm over carb throats and go from carb to carb as you pull the cord.
 

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Discussion Starter #52
I’m getting a new choke cable for it to see if that makes a difference. If not, I’ll be tearing it down hopefully one last time and replacing gaskets and such. Wish me luck. I can post pics of the piston I pulled out during the first rebuild if anyone would like to see it.
 
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