Just replaced changed pistons, now engine is making a hard knocking sound
- Thread starter kidwoo
- Start date
Just kidding ya.
There is no crank case oil.
Here is what I think your problem is. When you pulled the Cylinders. Antifreeze dumped into your bottom end. Oil is floating on top. (Paper towel green issue) you are having.
Suggestion. Tip the sled on it's side and dump all the water and oil from the bottom end. Or get a shop vac with a small hose and suck it out. All that water and oil will be causing a hydro-lock and bad knocking.
There is no crank case oil.
Here is what I think your problem is. When you pulled the Cylinders. Antifreeze dumped into your bottom end. Oil is floating on top. (Paper towel green issue) you are having.
Suggestion. Tip the sled on it's side and dump all the water and oil from the bottom end. Or get a shop vac with a small hose and suck it out. All that water and oil will be causing a hydro-lock and bad knocking.
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I figured I'd hit that while changing my tail light fluid and suspension batteries.
So there's not supposed to be fluid in the crank case..............yup......we got a problem houston. Shop vac on the way.
Thanks again guys. I'm learnin
I did the same thing on my first Doo 800. Filled it with water. I just tipped the sled on it's side and dumped it out.
If you take off the bottom coolant hose from the front of the engine before you pull the cylinders, most of the fluid will drain from the cylinders and not dump into your bottom end.
Two cycle engines don't have crank case oil like other engines. They rely on either oil injected into the bottom end and then the fuel mixes with the oil as it is passed through the ports and into the top end or oil mixed with the fuel in premix.
If you take off the bottom coolant hose from the front of the engine before you pull the cylinders, most of the fluid will drain from the cylinders and not dump into your bottom end.
Two cycle engines don't have crank case oil like other engines. They rely on either oil injected into the bottom end and then the fuel mixes with the oil as it is passed through the ports and into the top end or oil mixed with the fuel in premix.
I think the problem is solved.
Hopefully.
Good work fellas!
Hopefully.
Good work fellas!
I went back with a siphon pump and my shop vac with a tube duct taped to the end.
uh........yeah
There was somewhere between a few drops and a quart of antifreeze sitting in there. Considering I drained the coolant the first time the same way I took it apart today, I'm sure it was the combo of two cylinder drainings sitting in there
It's pretty much bone dry now. Now I wonder what coolant does to crankshaft bearings
But I should have some new carb boots in the next day or two then it goes back together.
Thanks for all the replies. Very much appreciated.
uh........yeah
There was somewhere between a few drops and a quart of antifreeze sitting in there. Considering I drained the coolant the first time the same way I took it apart today, I'm sure it was the combo of two cylinder drainings sitting in there
It's pretty much bone dry now. Now I wonder what coolant does to crankshaft bearings
But I should have some new carb boots in the next day or two then it goes back together.
Thanks for all the replies. Very much appreciated.
Your fine. The coolant wouldn't have hurt your bearings for the short time it was in there.
Your bearings should have had a healthy dose of two stroke oil film on them anyhow.
You could squirt a little on them and turn it over while you are waiting for your carb boots.
Yep, a quart of water is alot. I am suprised it even started or pulled over. Hope the hammering of hydo-lock didn't cause any other damage.
Your bearings should have had a healthy dose of two stroke oil film on them anyhow.
You could squirt a little on them and turn it over while you are waiting for your carb boots.
Yep, a quart of water is alot. I am suprised it even started or pulled over. Hope the hammering of hydo-lock didn't cause any other damage.
check your clutch, sometimes they go out and make terrible noises.
Well like I said, I don't think there would have been that much when I had it first reassembled. What I saw was from pulling the jugs and dropping collant into them two times. But yeah, even half that amount sucks.
No scoring or scratching of the pistons or cylinders. Everything still looks clean and smooth. In all honesty I probably had the thing at a total running time of less than a minute. As soon as I heard that knocking, I flipped out.
My coolant draining will include that bottom hose from now on. Lesson learned.
when my crankcase was open for a while when cylinders were down south etc...i fill whole crankcase with oil to submerge crank brgs and sucked out just prior to re-assembly...ok hope ya up and running soon...
IT'S ALIVE!!!!!!
Got it back together and started it up. Revved it up for a little and no clickety clack. And I didn't even have to change the crankcase oil!
It was idling a little low at first and just out of boredom I kept pressing the odometer button. I don't know what happened but I must have cut off it's balls while I was in there. It only reads kilometers now. So it works but it's french.
(and yeah this is my first doo so if it's something stoopid to get it to read miles, go ahead and assume I don't know it)
Got it back together and started it up. Revved it up for a little and no clickety clack. And I didn't even have to change the crankcase oil!
It was idling a little low at first and just out of boredom I kept pressing the odometer button. I don't know what happened but I must have cut off it's balls while I was in there. It only reads kilometers now. So it works but it's french.
(and yeah this is my first doo so if it's something stoopid to get it to read miles, go ahead and assume I don't know it)
pistons
Did you measure the piston to cylinder clearance, on some yrs they have a A-B-C piston, there about .0001in different, if you have to much clearance it will knock cold.
Make sure your in spec, .0045-.0055 clearance, any more then that and it will make noise cold at idle, and they will crack the skirts if you run them with to much clearance.
Did you measure the piston to cylinder clearance, on some yrs they have a A-B-C piston, there about .0001in different, if you have to much clearance it will knock cold.
Make sure your in spec, .0045-.0055 clearance, any more then that and it will make noise cold at idle, and they will crack the skirts if you run them with to much clearance.
P
pyxle
Well-known member
kmh - mph
The black, one wire connector on the L.H. upper frame, next to the headlight is plugged in.
Unplug it and it will read miles.
IT'S ALIVE!!!!!!
...I don't know what happened but I must have cut off it's balls while I was in there. It only reads kilometers now. So it works but it's french.
(and yeah this is my first doo so if it's something stoopid to get it to read miles, go ahead and assume I don't know it)
The black, one wire connector on the L.H. upper frame, next to the headlight is plugged in.
Unplug it and it will read miles.
