Engine Teardown

AMT82xs650 · Full Member Joined: Dec 22, 2007 Posts: 17

82 XS650 won in a game of 8-ball. The engine is frozen, and when I pulled off the alternator cover I discoverd this... I'm betting it's time to pull the engine and tear it down...

nj1639 · Posted: April 23, 2008, 6:42 pm Post subject: Re: Engine Teardown

Looks like a victim of Katrina. What's the oil look like?

AMT82xs650 · Full Member Joined: Dec 22, 2007 Posts: 17

I haven't drained it yet. I'm pretty sure that the bike hasn't been submerged. It's belonged to a friend of mine since around 1990. He rode it for a few years until it started to have carb problems. Its been stored in a shed ever since.

Cooltouch · Posted: April 23, 2008, 7:15 pm Post subject: Re: Engine Teardown

I bought a 77D a few years back. It had been sitting out in the weather for years, without carbs. One of the intakes had been partially open when it was parked, and water got down inside the combustion chamber, freezing up the motor eventually.

I've heard of folks pouring Marvel Mystery Oil into the CCs and then letting it sit for a long time, and the motor eventually freeing up. I wasn't that patient. To remove the cylinders, I had to tap on the pistons with a piece of wood and a mallet. Ended up slightly scoring a piston, but it wasn't too bad. I was planning to install a big bore kit anyway. I was surprised to discover that the bores were actually in good shape -- as was the rest of the motor after all that time sitting out in the elements.

If you're patient, I'd recommend you try the MMO. You might be able to reuse the pistons and get by without having to have the cylinders bored oversize.

Best,

ichael

AMT82xs650 · Full Member Joined: Dec 22, 2007 Posts: 17

I read about the Marvel Mystery Oil trick somewhere on this forum. I poured about a quarter inch of MMO onto the tops of the pistons last saturday. About how long should I let it sit before I start the teardown? Should I pour it into the crankcase as well? Will it contminate the clutchplates if I put it in the crankcase?

xsjohn · Posted: April 23, 2008, 11:00 pm Post subject: Re: Engine Teardown

Had one of those water soaked for years motors in the garage (a guift)....the pistons are so frozen that even a serious beating won't free them......maybe a hydraulic press somehow will save the crank which being soaked in oil is still good.....just kinda stuck in the middle.....already stole the trans and shift forks........had good clutch and was happy to have that........

xsjohn

Cooltouch · Posted: April 24, 2008, 9:32 am Post subject: Re: Engine Teardown

AMT82xs650 wrote:

I read about the Marvel Mystery Oil trick somewhere on this forum. I poured about a quarter inch of MMO onto the tops of the pistons last saturday. About how long should I let it sit before I start the teardown? Should I pour it into the crankcase as well? Will it contminate the clutchplates if I put it in the crankcase?

I suspect the time needed for soaking varies depending on the severity of the freeze-up. I don't see why you would need to put any in the crankcase, unless the crankcase has no oil. Betcha it does, though.

You might try bumping the kickstarter periodically (with the spark plugs out) and see if you can detect any movement.

Best,

ichael

jimmythetrucker · Full Member Joined: Mar 12, 2008 Posts: 1283

What harm could it do at this point to hold off on the Marvel Mystery Oil and just pour the cylinders full of Sea Foam? That might eat the rust and corrosion off them rings, don'tcha think?

I've never tried it myself, but what the hey?

xsjohn · Posted: April 24, 2008, 11:22 am Post subject: Re: Engine Teardown

Since you asked......might be a bit harder to avoid the mist down there and end up with more oil in the breather.....they did make quite an attemp to baffel out the oil mist on the stock breather.assembly....besides we are only talking 2 lbs or so.....any decent date could handle that.......

xsjohn

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