Pistons stuck from setting

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bluehawk71

XS650 Enthusiast
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My 1972 Yamaha xs2 650 that set in a garage for 11yrs and pistons were stuck,,,,notice the word were stuck,,,,If freed up this morning,,,

Thanks to everone for there input on freeing the pistons

I used PB Blaster and two days ago added Transmission fluid,,,,,

thanks again

Will let u know when I get it running and how the top end is.
Thanks Patches
 
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My XS11 with only 6,999mi, sat for more than 20yrs was stuck as well. Shot Aero Kroil in the cylinders, put it in 5th and rocked the rear wheel everyday when I got home for a week, re-filling the cylinders each day until it freed up then tore it down for a rebuild.
 
Nah, the real thing. Regular coke. Seriously, more PB Blaster and a light tapping of a hammer and 2X4 to the piston. Daily.
 
Depends on why it's stuck. Light rust rings are easy, heavy rust is hard, other materials are harder still.

I've got an engine in my garage right now that has a bolt puller putting about a lot of pressure on the piston head and that sucker ain't moving.

If you're going to put anything like cola/molasses water etc. in the cylinder I'd instead recommend using h2o diluted phosphoric acid. Phosphoric acid is the active agent in cola/molasses but without the side effects. It's nontoxic, and reasonably harmless (take all precautions as always with all chemicals - gloves, eye protection and ventilation)

You first need to determine WHY it's stuck. A 50 buck harbor freight snake cam will tell you, or you can take the heads off.
 
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Well, I guess I can weigh in on this one being that I have recently tore apart three motors that were top end seized. Two are going to be my personal motors and I will be selling the third. One is a somewhat rare XS1 motor and I'm going to hold on to that one for sure. (all 4 matching valve covers.... It's the little things..... And longer connecting rods)

First, you're probably going to need to do a top end rebuild no matter what.
Rust has formed between the cylinder walls and pistons. This creates pitting on the cylinder wall. If you want to do things right, go to at least one over pistons and rings. Send the pistons with the cylinders to the machine shop and give them the proper piston clearance dimensions to match the pistons to the new cylinder bore.

As how to get the pistons out of the cylinders you are going to need to pull the rocker box, cam and head. Take a look down in the cylinders and decide which piston is sticking. Usually it's just one because the other cylinder's valves were probably both closed.

I take a 2"x2" block of aluminium that is about a foot long and stick it down the cylinder on top of the center of the piston (a 2x2 piece of wood would work too). Now grab a 3lb hammer or the biggest dead blow you have. I prefer my 3lb solid steel hammer aka precision adjustment tool. Now beat the shit out of it until the pistons frees from the cylinder. You will not harms the connecting rods unless the pistons are at the absolute top or bottom of their stroke, and luckily all three of mine were in the middle.

Some may say that you may be able to get away with putting the bike in 5th and trying to rock it to free the cylinder. This may work, but you're still going to need a rebuild. I've seen guys say,"just run it" and you may be able to for a bit, but the cylinder walls have been damaged as well as the rings and this will cause you problems in the future. I prefer to have piece of mind rather then waiting for things to fail.

Whenever I get a motor like this I do:

New rings/pistons
Gasket kit
Valve seals (while I'm there)
New cam chain guide
Thorough cleaning
New cam chain (depending on the miles on the motor)
Clean both filters (your sump filter is probably torn so go ahead and repair it too)

If you have the time, I like to power wash the case, disassemble and bead blast the cylinders, head, and rocker box. The clean up the casting marks and a mild head porting.
I know it sounds like a lot for some, but I feel like that's probably the minimum.

It's not cheap to do it right, but then again it rarely is.

Hope this helps.
 
rpgoerlich said:
My XS11 with only 6,999mi, sat for more than 20yrs was stuck as well. Shot Aero Kroil in the cylinders, put it in 5th and rocked the rear wheel everyday when I got home for a week, re-filling the cylinders each day until it freed up then tore it down for a rebuild.
Click to expand...

Who sales this kroil?
 
diet coke and molasses both have phosphoric acid which derusts. you could and should probably just cut out the middleman and put in phosphoric acid (home depot) diluted 4:1 or so depending on concentration.
 
LOL, a thousand more on the asking price....does that get spread around amongst those that gave the good advice when the bike is sold?? Will the new buyer be informed of the previously locked up engine?? Inquireing minds want to know!
Tune in tomorrow, same time, same station............


http://www.xs650.com/forum/showthread.php?t=11269
being honest, that's a plus.
 
This OP is killing me. $1000 more for spraying some PB in a cylinder...... WTF?

The top end will still need to be rebuilt, and its people like this that I hate to give free advice too.

I feel sorry for whoever buys this bike.
 
Patches said:
So I gather you're going to try to free up this motor without doing the proper work, get the bike to run, and sell it to some unsuspecting buyer. :eek:

I think I'm done helping......
Click to expand...

I would never try to sale it to any one with out telling them everthing that was and is wrong with the bike, At least the motor is free now, I am going to keep putting pb blaster in th cyclinders for a couple of days, then change the oil and add marvel oil additive, I did this to another bike and it has not smoked since..If it does not work then I will do a top end or sale and let the buyer do the top end, I am not trying to cheat any.:doh:
 

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