one piston freed up but other one still froze?

[hitace]

on my 1955 evinrude i sprayed some pb blaster in th spark plug holes and on the pistons.2 days later i try to turn the flywheel and the bottom piston is nice and freed up but the top one will not budge it also looked alot worse off also on the top spark plug it was stripped and was hell getting out.the spark plug also looked alto worse the the other one it looked as tho it got hot.if it did get hot do you think the powerhead is done.

 

[hitace]

Re: one piston freed up but other one still froze?

heres a pic of the froze piston and spark plug

 

[tashasdaddy]

Re: one piston freed up but other one still froze?

looks like water intrusion rust.

 

[iwombat]

Re: one piston freed up but other one still froze?

Couple of things you can do.

1) I've had a lot better luck freeing up rust with an ATF & diesel mix than with PB blaster or the like. Worth a try at least.

2) (As heard elsewhere on this board) Make a grease fitting that will fit your plug hole and pressurize the top end with grease. Keep up the pressure by pumping in more grease a couple of times a day for a week or so. It usually only takes a couple of minutes to a couple of days.

If that won't do it, use it as an anchor.

 

[hitace]

Re: one piston freed up but other one still froze?

ok thanks i just really hope this thing dint overheat

 

[jspringator]

Re: one piston freed up but other one still froze?

I have a similar problem on my 3 1/2 Tohatsu, and a post in that forum. I kept filling up the cylinder with PB blaster and it kept running out somewhere. I assume through one of the ports. What will happen if I dump a bunch of oil in there? Where will it go? BTW my plugs were tarrey with old oil; no rust.

 

[iwombat]

Re: one piston freed up but other one still froze?

A third thought. Sometimes temperature extremes can get things going too. If you've got a gas bbq go from heated bbq (turn the gas off before putting it in there and don't get it too hot) to freezer and back again. I pop bronze valve guides out of heads after they've had a good freezing. Much easier.

 

[hitace]

Re: one piston freed up but other one still froze?

so maybe heat the pistons with a tourch then put the outboard in a freezer and do it over and over???

 

[iwombat]

Re: one piston freed up but other one still froze?

I wouldn't hit it with a torch you'll get a fire from all the oil. Freeze the unit, the n heat up the outside of the block. Your pistons and rings will heat up last and hopefully separate a bit from the block.

Penetrating oil, then the grease thing is still your best bet. I'm just adding to the arsenal.

 

[hitace]

Re: one piston freed up but other one still froze?

ok thanks tomorrow im going to the home depot and buying every kind of oil lube penetration oil pb blaster and aything els they have

 

[F_R]

Re: one piston freed up but other one still froze?

Personally, I think you are going to end up destroying this motor if it isn't already too far gone. That thing has had water in it and there is a very good chance that the rods are stuck too. If they are and you rotate them, it will grind out the bearing surface (they are aluminum). Not only that, but even if you do get it freed up enough to turn over, lots of luck getting those rings free.

That motor needs to come apart.

 

[Chinewalker]

Re: one piston freed up but other one still froze?

If I read this correctly, you've got one piston freed up when you turn the flywheel, and the other one is not moving? If this is correct, then you have a bigger issue than a stuck piston - you've got a broken crankshaft, rod or piston. Both pistons are connected to the crankshaft so if the crankshaft is turning then both pistons need to be moving...
- Scott

 

[F_R]

Re: one piston freed up but other one still froze?

Here is a piston that I recently beat out of a similarly froze motor. Anybody have any illusions about this running with just a spritz or two of PB Blaster?

 

[Xcusme]

Re: one piston freed up but other one still froze?

Ahh that's no big deal......a little emery cloth work and that puppy will be good to go....no problem....

 

[iwombat]

Re: one piston freed up but other one still froze?

Whoa!

I missed the part about turning the flywheel. I had assumed the whole thing was disassembled already and the only thing hanging in there was this last piston. Guess I read through the post too fast.


Yeah, you got something seriously wrong if one is moving and the other isn't.