Author Topic: Am I Screwed (Read 6127 times)

DanJ · « **on:** October 25, 2013, 09:00:39 AM »

I bought my bike with what I figured was a stuck motor from sitting for 30+ years. Well I've soaked and resoaked with every substance known to man, then took the head off and banged on the pistons and nothings moving. I've been trying to take the cylinder off and that won't budge either. Two cylinders hold fluid, the other two the fluid seeps by the piston. Anyone have any suggestions?

Xnavylfr · « **Reply #1 on:** October 25, 2013, 09:12:29 AM »

Use some heat on the sleeves of the 2 cylinders that are stuck. Try to concentrate the heat on the steel on not the pistons.

Xnavylfr(CHUCK)

Sprocket75 · « **Reply #2 on:** October 25, 2013, 09:44:20 AM »

Patience! That is my suggestion. Stop, take a deep breath, and lets look at the problem methodically. You say that 2 of the cylinders hold fluid, the other 2 do not. Correct? So, lets first take a look at the 2 that do. Can you see rust around the edges of the pistons? Understand that the pistons and rings fit to extremely tight tolerances...so if they are "canned" sideways a little or rusted a little, they will lock. Try tapping GENTLY with a rubber mallet and a block of wood. GENTLY! Try some rust remover applied around the edges carefully. Maybe even a little Sea Foam. Have you opened the bottom end up? What's in the pan? Rust? Gunk? Water? How about the crank? You have to take your time with this. Be methodical. Try to give us more information...pictures speak volume...so that we can help you. Let us know.

phil71 · « **Reply #3 on:** October 25, 2013, 09:47:21 AM »

ATF and acetone , heat and time.

Dream750 · « **Reply #4 on:** October 25, 2013, 09:53:50 AM »

This looks like an interesting method, but I haven’t personally tried it.

http://forums.sohc4.net/index.php?topic=84354.0

madmtnmotors · « **Reply #5 on:** October 25, 2013, 09:54:35 AM »

http://bit.ly/1g0lRRl

Third result is directly from this forum.

When using the Google search at the top left of this forum it's the first result.

Powderman · « **Reply #6 on:** October 25, 2013, 09:56:13 AM »

Keep in mind while you are trying to push those pistons you are also trying to turn the crank and everything connected to it. So it isn't always just the pistons that are seized.

Sprocket75 · « **Reply #7 on:** October 25, 2013, 09:58:22 AM »

Quote from: Powderman on October 25, 2013, 09:56:13 AM

Keep in mind while you are trying to push those pistons you are also trying to turn the crank and everything connected to it. So it isn't always just the pistons that are seized.

+1 on that!

DanJ · « **Reply #8 on:** October 25, 2013, 10:00:12 AM »

I've used ATF and Acetone, Marvel Mystery Oil and Acetone, Kerosene and Acetone, Kroil and Acetone. and have been soak it for well over a month now. I've been hitting the pistons with a nylon cylinder and a dead blow hammer. I have not looked at the bottom end yet, I was thinking of flipping the motor over and looking. The pistons have an accumulation of soot and the cylinders look like they have a rust tinge but nothing like heavy corrosion. I can take a couple of picture this weekend. I'll also try some heat

DanJ · « **Reply #9 on:** October 25, 2013, 10:01:32 AM »

Quote from: Powderman on October 25, 2013, 09:56:13 AM

Keep in mind while you are trying to push those pistons you are also trying to turn the crank and everything connected to it. So it isn't always just the pistons that are seized.

I've thought of that

Sprocket75 · « **Reply #10 on:** October 25, 2013, 11:03:39 AM »

The gel type rust remover applied around the edges of the piston might help. It stays put where it needs to. Obviously, you are most likely going to have to re-hone (or re-sleeve) the cylinder walls once all is said and done, but that's part of the fun! I agree 100% with Powderman about the crank. You really need to open that bottom end and have a look.

lucky · « **Reply #11 on:** October 25, 2013, 11:06:33 AM »

You are not "screwed".

It WILL come apart.
The question is how many parts will you break or damage to get it apart?

larsenken · « **Reply #12 on:** October 25, 2013, 12:57:14 PM »

Easy thing to try if it still in the frame is to, believe it or not roll it down a hill with the clutch in and gearbox in second gain momentum and let the clutch out. I have busted many of honda engines loose doing this. But if it doesnt work it is ugly to push the bike back up the hill!

754 · « **Reply #13 on:** October 25, 2013, 12:59:14 PM »

Just split the cases , and undo the rod caps...

dave500 · « **Reply #14 on:** October 25, 2013, 01:20:34 PM »

you beat me to it 754,dont be screwed,get it unscrewed.

banzaibob · « **Reply #15 on:** October 25, 2013, 01:25:03 PM »

Snip the cam chain. You're gonna need a new one anyway.

Toxic · « **Reply #16 on:** October 25, 2013, 01:49:37 PM »

are you using a socket on the nut behind the points cover?

I think it is 22 or 23mm. That and a little persuasion, like a three foot breaker bar on the end of the ratchet. Be gentle as you don't want to break anything.

If that doesn't work take the bottom end off.

dave500 · « **Reply #17 on:** October 25, 2013, 01:52:15 PM »

dont lean on that nut behind the points cover at all!you will break it or the advance unit drive pin!on the other side try leaning on the alternator rotor nut instead.

Nic · « **Reply #18 on:** October 25, 2013, 02:07:14 PM »

Quote from: Toxic on October 25, 2013, 01:49:37 PM

are you using a socket on the nut behind the points cover?

I think it is 22 or 23mm. That and a little persuasion, like a three foot breaker bar on the end of the ratchet. Be gentle as you don't want to break anything.

with advice like that, who needs enemas.

get the bloody cases split n undo the rods FFS

lucky · « **Reply #19 on:** October 25, 2013, 02:15:30 PM »

Quote from: 754 on October 25, 2013, 12:59:14 PM

Just split the cases , and undo the rod caps...

That always works and usually it needs it anyway.

Leino · « **Reply #20 on:** October 25, 2013, 02:20:04 PM »

Engine like that ain't gonna be a runner without a complete rebuild anyway.
Stop messing around, pull it apart and replace everything that needs to be replaced.

754 · « **Reply #21 on:** October 25, 2013, 02:30:28 PM »

F its that stuck, time to look at the lower end anyway..

cakey · « **Reply #22 on:** October 25, 2013, 02:36:40 PM »

I just had similar to you with my engine rebuild Danj. Number 4 was frozen in the cylinder real good. I had to split the cases, undo the rod caps and remove the barrels and guilty piston and rod as one unit.

Soaked it like you have and put the barrels in between two blocks of wood and knocked the piston through with a bit of wood and a mallet. It took a couple of goes but it came out. Never would have if I didn't split the cases. It's now been re bored bigger size because of the rust marks from where the rings were seized. Honing didn't get rid of it.

DanJ · « **Reply #23 on:** October 25, 2013, 03:18:13 PM »

I flipped the motor and pulled the oil cover off and looked inside with a flashlight everything I can see looks to be in excellent shape and very clean, no rust or metal chips anywhere. I think one of or two the pistons is stuck real good I guess it's time to follow cakey's lead and others suggestion and split the cases and remove the rod caps.

cakey · « **Reply #24 on:** October 25, 2013, 03:58:53 PM »

Sorry mate it's the only way.

I take heaps of photos as I go as well and if you get stuck somewhere no matter how silly you think it is then stop and ask the question from these guys before you force anything. I learnt the hard way not to rush and ask questions.

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Author Topic: Am I Screwed (Read 6127 times)

Nic