Engine Trouble...what's your guess?

[JLanphear]

Hey guys....this is pretty much a "bored at work post", but I would like to hear your opinions.

Yesterday I took my EX for a ride....about an hour into it I was hanging a nice long wheelie (probably going on close to a mile), when suddenly it lost power and the front wheels dropped. I then heard a noise from the engine that was surely not normal. It was still running, and had a fair amount of power, but there was a section of the RPM range where it was just not right.

Anyway, long story short....Get it home, first thought is I ran it out of oil because I have been putting off an oil change for quite some time....Unfortunately I was right. Not a drop on the dipstick. I added a couple of quarts, and started the quad back up. It sounded slightly better, but still was not right. Looks like I'm going to have to tear it down.

My goal is to try to do the work myself with the help of some friends. I have never done engine work before, but I figure now is a good time to learn.

The quad starts and runs....at idle you can almost here a "slapping" noise....more like a "clink clink" actually. It gets worse if you Rev the quad, but can almost go away at the right RPM. Like I mentioned before, it still has a fair amount of power at certain RPM's also...I can still lift the front tires up in 5th gear.

Any guesses as to what this could be? What to check? What could be easily missed? What I should do while its apart?

Like I said, I have no experience with engines and I want to learn by doing this (or watching it be done) myself.

And....no jokes about the oil thing....haha I feel dumb enough already. That will teach me to procrastinate, won't it.

Thanks for reading.

-Josh

[NacsMXer]

I seized and bent both my intake valves when I found that I had not a drop on the dipstick like you. Wasn't a very pretty sound at all. I believe the head is the first thing to become starved of its crucial oil supply in a low-oil condition so you may have wiped out your cam, rocker(s), etc. Pop the valve cover and see if anything's going on in there. Good luck with the diagnosis :) :(

[416exduner]

Like he said, check all those things to make sure you're going fine. When the pistion strokes up and down the cylinder, oil is what lubricates the rings along the cylinder walls. I would suggest either boring it and getting a bigger piston or just getting the cylinder honed and put new rings in it, this will allow you to get maximum compression. If there was no oil in the engine, metal on metal grinding would have occured and left scratches in the cylinder walls.

Another thing to think about is that if metal on metal grinding did occur, there are metal shavings in the whole engine, if there are then you either need to have it flushed or get as many out as possible. I suggest just getting out as many as possible and then changing your oil soon after the rebuild, like after the first one or two rides. This will flush all those out for you.

Hope this helps, just ask if you have anymore questions.

[prepracing]

when you have the quad at that angle for that long period of time all the oil flows to the bottom and out of the tank and the oil pump will not circulate it and you will burn your rings up. Especially when your already low on oil :D

[JLanphear]

Thanks guys.....I'm pretty much looking for what the most common things are to check once the engine is apart. I mean you obviously are going to be looking at the piston and rings, as well as the cylinder wall, but I don't know if everything else is so obvious.

Thanks for the help.

-Josh