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Discussion Starter · #1 ·
I have been trying to remove this thing and it won't budge you might have seen the pic of the rusted cylinder if not here is another.

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I have removed the cylinder studs and stuck them into a piece of cardboard in the position they came out. I have been smacking the bottom of the cylinder with a dead blow rubber mallet trying to get it to separate, don't worry I have only been hitting on the sides where the fins are connected solid together. Manual says lift off, yea right. I have been keeping it sprayed with PB blaster since last week. Any ideas? My next thought is to separate the cases, I am doing that any way. Here is where i really don't know what I'm doing, by looking at the book it looks like it would not be simple to remove the piston rods like you can in a car by taking the piston rod journal off. Do you have to remove the crank and flywheels and take that assembly apart to remove the piston rods? I was thinking, maybe just wondering, if I could cut the piston rods in half, remove the cylinders and pound the pistons out or use it for a boat anchor.
 

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First and foremost - aside from taking it apart, what are you trying to accomplish? :eek:

I mean, is there a needed part in there somewhere you are trying to get to?
Do you maybe have some hope of resurrecting this motor?
Cutting the rods is pretty drastic!!!! :-?

Some idea of your goal may aid in making suggestions to reach it. ;)

That said. My favorite penetrating oil for a long time now has been a 50/50 mix of acetone and ATF (auto. trans. fluid). You can make a 1/2 gal. for about five bucks. Use it liberally! Fill the cylinders with it and let stand overnight. My guess is those pistons are done anyway. Have you tried tapping them with the mallet? It is the pistons & rods that are holding the top to the bottom you know. ;)

EDIT - BTW, you can use a dowell or even a piece of 2x4 to tap on that left piston. The goal rather than moving them is simply to free them from the cylinders. Annnndddd, I wanted to add that you have a awesome looking cam chain roller down in there! My guess is this motor doesn't have many miles on it.
 

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I use an air chisel to remove pistons that are stuck in like that. Most of the time the air chisel will get them moving, but on a few occasions, I have chiseled the piston apart. Either way, the pistons are removed.
TOOLS
 

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I keep looking at this thing. :(

You say you're only tapping on the cylinders where the fins are connected. I really don't think you need to worry about that unless you have plans to re-bore it. :cool: Likewise the rubber mallet. If you want to get this apart I think it's gonna take the BFH. I'm really curious about why you want to take it apart though. At this stage, destroying the cylinders just to retrieve that cam roller looks like a good idea. ;)

As I mentioned earlier though, from the looks of that cam roller, there are probably some good parts in the big end to. Assuming the oil fill cap wasn't lost with the head, the innards should be relatively protected from all this nastiness.
 

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Discussion Starter · #6 ·
That suks I typed for 10 min and it must have timed out and erased everything. I'll try again tomorrow.
 

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That suks I typed for 10 min and it must have timed out and erased everything. I'll try again tomorrow.
:eek: :eek: :eek:



Looking forward to it!
 

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Degrease the top of the pistons and pour some Draino on them. The stuff eats aluminum and won't harm the cast iron sleeves.
 

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Go buy/borrow a steering wheel puller or a drum brake puller, bolt it to the top of the cylinder with the studs and appropriate spacers and PUSH the piston out. Once it starts moving it may just pop right out.
 

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Discussion Starter · #10 ·
Knoxes, I like your idea from that link with the bar clamps and a block on top of the pistons. The other methods using the cylinder bolts, I removed them and don't really want to put them back just to try those methods.
oupa, I am just trying to salvage any and all the parts I can and I probably won't try to put this back together and get it running but it is still in the back of my mind. I haven't been taping on it I have been beating on it. I will try putting a block or something on the piston and hitting it to try to get it to move. It look like one piston is TDC and the rusted one at BDC so I don't know if the crank will rotate when pushing on the pistons. The bike was lying on it's side with the stator cover missing and pointing to the sky and guess it rained in it for some time. One way or the other I hope to have it separated today. I will give an update and post a pic of the method that works later .
 

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Okay. That's kinda what I was thinking (about the disassembly). The idea in beating on them, more so than getting the pistons to move is to break the rust bond. If the side cover was missing as well you may be going to a lot of work for little benefit. :( My guess is everything else inside is going to look similar to those cylinders. You STILL have a great chain roller in there though!:D Other than that, referring to your original post, I'm inclined more and more toward "boat anchor."
 

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I'm sure opinions vary on this, but I've always been concerned about beating on pistons to get the out of rusted cylinders because of the shock on the big end of the rod. I realize that explosions go on inside the engine constantly, but those are under controlled circumstances and aren't the same (IMO) as using a 2 lb hammer and driving down on the top of the piston when the rest of the engine is sitting still... I'd try the puller method frogman suggested, along with a little heat and penetrant, before I'd hammer on the pistons
 

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I do not repeat myself often, but again, use an air chisel and they will come right out. And this does not cause the stress of beating on the components like using a big hammer or risk pulling a stud out of the case.
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Patience.........and time.

They'll come out.

Post some pix when they do.
 

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Discussion Starter · #15 ·
Well end of round one and they won't be out today. I tried Knoxes idea but with big C-clamps and I didn't take a pic but i cut a block of wood that stuck up out of the cylinder when placed on the rusted piston. I then took a scrap of angle iron and used the clamps to go across side to side and tightened them down even had to use a cheater bar to tighten the clamps so I had quite a bit of pressure on the head pulling up. Didn't budge. So here is how it looks now, I have it soaking in a 55gal plastic barrel that has been cut in half. I had about 10 gal of old gasoline from a couple fuel pump projects and I poured that and about a gal of old used oil in the barrel and stuck it right in there. There is no way for it to ignite unless God send a bolt of lightning down.

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Discussion Starter · #16 ·
Degrease the top of the pistons and pour some Draino on them. The stuff eats aluminum and won't harm the cast iron sleeves.
A couple questions here, liquid Draino? How fast does it work? If it seeps past the piston and gets into the bottom end won't that do damage to the cases?
Still having no luck beating on the cyl, I'm hitting on the casting for the cam roller, my thought is that it is giving upward pressure to the cyl.

Knoxes: I think putting a couple of the cyl bolts back in with spacers and a puller to free pistons would be hampered by the TDC and BDC position of the pistons.

Tools: I'm leaning toward the air chisel idea but am still thinking about splitting the cases and cutting piston rods then pounding out the pistons from the cyl.

At least I'm getting the block clean.
 

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I've done battle with a couple like that. What I ended up doing was buying a hole saw that was a couple mil smaller than the bore. Buy a good one, I burned out a crappy one and didn't get anywhere. The one that ended up working for multiple rounds was a Diablo brand bi-metal. I squirted some thread cutting oil in there, and then VERY CAREFULLY started boring into the piston. The right combination of size, caution, and luck will cut it out and leave your barrels able to be machined. Good luck!

Cut Piston.jpg
 

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A couple questions here, liquid Draino? How fast does it work? If it seeps past the piston and gets into the bottom end won't that do damage to the cases?
Still having no luck beating on the cyl, I'm hitting on the casting for the cam roller, my thought is that it is giving upward pressure to the cyl.

Knoxes: I think putting a couple of the cyl bolts back in with spacers and a puller to free pistons would be hampered by the TDC and BDC position of the pistons.
I think everyone's advice so far is about loosening the pistons and I think you're talking about loosening the jugs. If I understand you correctly (and I'm not sure that I do), you're hitting perpendicular to the piston stroke direction? Is this because the jugs will not separate from the cases?

If that's the case, then first make sure it's in neutral (so the crank can spin). Once it's in neutral, then the rotating assembly can turn (a bit), which will move the jugs up and down because they're now rusted to the pistons.
 

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Discussion Starter · #19 ·
I was not sure if the jugs were rusted on or not and the soaking was to loosen anything that might have been keeping the cyl from being removed, the rusted piston for sure. And yes I have been hitting on the forward casting for the cam chain roller to separate the cyl from the block, that area seemed to be thick and stood out enough that I could wack it and not hit fins. I also hit on the sides where the fins are connected in the casting, only didn't hit as hard there. Well I got it separated but still not off, about 1/2" separation and I stuck it back in the barrel till tomorrow. Budlite282: patience and time...

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I was not sure if the jugs were rusted on or not and the soaking was to loosen anything that might have been keeping the cyl from being removed, the rusted piston for sure. And yes I have been hitting on the forward casting for the cam chain roller to separate the cyl from the block, that area seemed to be thick and stood out enough that I could wack it and not hit fins. I also hit on the sides where the fins are connected in the casting, only didn't hit as hard there. Well I got it separated but still not off, about 1/2" separation and I stuck it back in the barrel till tomorrow. Budlite282: patience and time...

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xactly...............cool beans dude...
 
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