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Discussion Starter #1
Hello,
I recently rebuilt the top end, started and ran on bench for total of 1/2 hour, it was basically for about 5 min till engine was good and warm then let it cool then repeated 3 more times for total of 20 min.

Everything seemed perfect.

Next day started it still on bench and it ran for 1 min. and then it died. Wouldnt restart. Pulled plug and soaked with water.
Pulled it apart again and put new headgasket on it. Back together and still wont run because of water in cylinder.
Pulled it apart again had head machined. New head gasket and then back together.

Started engine ran great for 1/2 hour in 5 min. increments
Came out next day and started it. Ran great for a min and then water in cylinder again.

I have drained the crankcase and got a little residual fuel out of it.
I drained countershaft and originally got some water out of it (assuming it accumulated from many river crossing over the years I have owned it and my ignorance in not knowing that this two stroke has engine oil in it to lube counter shaft bearings)

After starting I again drained both areas and have nothing in them of any significance. (of coursed it was only run for 30 min and so not much might have accumulated n that amount of time)

The pull start area has no water in it although before rebuild it did.(assuming that was also from river crossings)

Questions.

Could I be getting water into combustion chamber from leaking water pump seals?
Could my break in procedure be causing the problem? ( short multiple run times )
Should I have taken it off the bench and ran in for half hour in one shot under load instead of the multiple 5 min short runs that i did.
Thinking that maybe since i warmed engine up and cooled off multiple times wthout retorque on head as opposed to starting and running for half hour straight then letting engine cool and retorque that this might be the issue.

Any thoughts would sure be appreciated, I am about ready to make a boat anchor out of this thing.
 

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Could I be getting water into combustion chamber from leaking water pump seals? NO

Could my break in procedure be causing the problem? ( short multiple run times ) NO

Should I have taken it off the bench and ran in for half hour in one shot under load instead of the multiple 5 min short runs that i did. NO

Thinking that maybe since i warmed engine up and cooled off multiple times wthout retorque on head as opposed to starting and running for half hour straight then letting engine cool and retorque that this might be the issue. I DOUBT IT

Any thoughts would sure be appreciated, I am about ready to make a boat anchor out of this thing.
The only way coolant can get into the cylinder is the head gasket or a crack in the head or cylinder
 

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Discussion Starter #3
Hey bird

cant argue with anything you are saying.

This counterbalance shaft and the water pump orientation in the motor I am very unfamiliar with so I dont put a whole lot of faith in what I think about it.

I read on another forum and one of the members mentioned that the water pump seals on this particular motor and pitted water pump shaft would allow water to get in the cylinder but he is the only one that answered that had that opinion. Everyone else had the same opinion as you and for that matter me to.

I would think that if the water pump seals are leaking that it would put water into the counterbalance area but not combustion chamber but after taking it apart and putting it back together way to many times I am questioning what I think.

Being new to this forum I did not realize that there was a specific section to post for the explorer so I will throw a post in there and then if everyone seems to think along the same lines on this as we do and there is not something special about this particular motor than I will take it apart again and see if I can find a crack in the cylinder.

thanks for taking the time to help
 

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Discussion Starter #4
Figured it out.
water leaking by water seal in water pump into intermediate case(where u put counter balance oil) On top of that I have a leaking crankshaft seal so it is sucking water in once it reaches high enough level in the intermediate case.
I was about to pull the cylinder and head off again and I drained each of the cases again, I actually had fuel in the intermediate case that had to of come through that crankshaft seal so it is not only leaking water(possibly sucking) in to the crankcase but it is pushing some of the fuel charge into the intermediate case.
So bagged pulling head and cylinder again and instead changed out water pump and crankshaft seals.
 

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I’m having an issue with my 02 400 explorer. I’ve rebuilt top end and corrected many issues... when I start the quad, I’m getting a lot, o men a lot of smoke. I’m wondering if the countershaft seal is bad... how difficult was it to change the water pump and countershaft seals?
 

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Two stroke engines normally smoke heavy when first started and more so after setting for an extended period - you will need to run it for a quarter to half an hour to determine anything. The type of two stroke oil and method of mixing will have an effect on how much it smokes too. Synthetic oils smoke less, but drip from the exhaust. Mineral oils smoke more, create carbon build-up in the exhaust, but drip out of the exhaust less or not at all. If premixing the oil, the type of oil and the type of fuel both play a part in the amount of smoke. Most oils will not mix with alcohol, so during premixing, the oil may force the alcohol to separate from the gasoline and the oil may not mix properly with the gas causing smoking, hard starting, low power and oil dripping from the exhaust.

That splooge inside the recoil cover is a mix of oil and water. It's not uncommon for a two stroke to push some oil past the crank seal behind the flywheel. The recoil cover will get water in it from the outside by migration through the recoil rope hole. That's why the recoil handle fits over the nipple on the cover and has a wire ring on it to seal out water when riding or washing. The cover can also get water in it from condensation. Over a long storage period, condensation will occur and collect. It's one of the reasons there is a drain plug on the bottom of the recoil chamber. It's supposed to drained periodically especially after a day of water crossings.

A table spoon of water from condensation and a tablespoon of oil from engine operation could result in the gooey mess you found when you removed the cover. Clean it, install the cover and run it for awhile checking the counterbalance oil each day. If the counterbalance oil level stays up and coolant is not being lost, just run it and enjoy. The smoke will decrease with run time and engine heat.
 

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Thanks for the response, this machine was a non runner when I purchased it. I’ve rebuilt the top end and replaced the starter so I’ve had the recoil cover off. When I bought it I was told it had a bad head gasket. I replaced the head, and installed a new gasket. I also found the radiator was empty and a blockage in the coolant hose between the cylinder and water pump. There was a lot of water in the counter shaft. I drained and refilled with proper oil. When I 1st rebuilt the top end I ran it without coolant and almost no smoke. Once I cleaned the cooling system it started smoking really bad. I’m a two stroke guy, but this is smoking way above the norm. The machine has only made one lap around my block and it never stopped smoking. It creates a huge cloud... almost a fig... So much so the fumes would burn your eyes...

So I’ll pull the side case and and replace the water pump bearing and seal. New gaskets on the counter shaft, outer case and I’d like to replace the crank seal. All I need is time...
 
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