Its not a factory hole. Looks like someone ran it into a tree or a rock. I can see the start or motor gear when I look into it. I'll do the best test I can tomorrow to see if I have a leak but it might not be for a few days some bad weather is coming my way and I don't have a garage to work in. Thanks for all the help I would have no idea what to do by myself. Once I do the test I'll post what I find.

 

I have never seen what your experiencing here, a hole in the crankcase. I will be following just to learn the outcome. Good luck!

 

a picture of said hole would help a lot...if its in your actual case thats not good

 

Since the starter is at the bottom of the engine,may be hard to see above it. You can kill two birds with one stone on this one. You have to pull the clutch cover and drive clutch to replace the main crank seal that leaks. While you're at it might as well slip off the driven clutch and backing plate. This gives you direct access to rear starter bracket bolts. Take them out along with two bolts holding the front of the starter that are inside the case behind the recoil assy. Pull the starter and bendix out as an assy and look over the engine case area. Sounds like you need a new starter anyway if it's cracked and might as well replace the bendix also. Easier now then later when you'd have to pull the flywheel. Plenty of them are on ebay.100 New Polaris Starter Drive Combo 250 300 350 400 | eBay

 

I did manage to work on it a little today and found out that the hole is not the problem. When it was idling I sprayed some carb cleaner in there and the revs did not change. I did find one leak in the carb boot. I ordered that part aftermarket along with a gasket set and the directions were wrong. It told me to put it on the intake boot from the airborne but when I was looking at some diagrams today I found out that goes on the carb boot. Sure enough when I turned on the quad and sprayed some carb cleaner on there it revved up. I put the o ring on correctly and that problem stopped. I found another air leak in one of the studs that connects the cylinder to the crank case; how would I fix this leak?

 

Looks like you're narrowing it down.Leaking around the stud is either because the base gasket isn't sealing properly or you have an imperfection in the cylinder base or engine casting causing it to seep air. Usually only way to fix that is to remove the cylinder and check it out. You HAVE to have a new base gasket and head gaskets,don't use an old one. Some base gaskets have a factory coating on one side,but no harm (if casting isn't a problem) to have a thin layer of Three Bond,Yamabond on each side to seal slight imperfections. Plus the gear you were probably looking at around the starter was the bendix teeth that fits inside. Best to replace this as your starter is trash anyway.

 

I ended up taking apart the whole engine again and found out that some of the old crank gasket was not removed all the way which would explain the air leak. I pealed all that off and used some high temp RTV to help completely seal it up. I put everything back on and now it won't even idle anymore. I also noticed that when I give it has to try and start it some of the fuel mixture stools back out of the carb when it is bogging down. Is this normal for 2 strokes? I also did find out that the electric start works, this project will really speed up now that I do t have to pull start it every time.

 

If you went to the trouble of taking the whole engine out then would have been the best time to just go ahead and have a new bore job and piston installed along with new gaskets and cranks seals. What is the compression reading?

 

The engine has already been rebored and has a brand new weisco piston and new head and crank gaskets. The compression reader I have is has a leak so it reads every engine bad but I used it anyway and even with a leaky tester it read 65psi. There is no way the compression is bad.

 

Just borrow a compression tester or you can even rent one from any auto store for just a refundable deposit. That's what you need to make sure of. You can't guess on that. That and also crank seals. If you haven't replaced them,this could be the cause of it not being able to take fuel and dribbling out of the carb.The engine has to have good bottom end compression to compress the gas and oil mixture. Plus the carb itself if the needle and seat are worn,float level off,can be the cause. Carb kits are all over ebay and other places.This is a simple engine but everything has to be right and work together. Even a cheap push in tester will do.http://www.tooltopia.com/mityvac-552...FQkwaQodROwCzQ