honda305 Home honda305 Auctions honda305 Gallery honda305 Forum


honda305.com Forum

Login
□ Search
□ FAQ 
□ 
Vintage Honda Owners,
Restorers, Riders and
Admirers

piston removal question

Want to keep a Restoration Log? Post it here! You can include photos. Suggested format: One Restoration per Thread; then keep adding your updates to the same thread...
Post Reply
big-b
honda305.com Member
Posts: 179
Joined: Mon Jul 26, 2004 12:45 pm
Location: Ashland, Mass.

piston removal question

Post by big-b » Mon Sep 06, 2010 2:26 pm

I'm trying to pull the head off my superhawk and the pistons seem to be stuck right at the bottom. The pistons move with some light tapping, (been soaking in kroil for a while now). I can lift the head up so the pistons slide almost all the way out the bottom but then they seem to stop. Someone told me sometimes the rings hang up on the bottom of the cylinder head and will break when you finally get it out. What am i missing?

Brian

User avatar
davomoto
honda305.com Member
Posts: 2508
Joined: Sat Nov 18, 2006 7:36 pm
Location: Marin County CA

Post by davomoto » Mon Sep 06, 2010 7:43 pm

Brian, it seems you are referring to the cylinder , not the head. The head houses the valves and cams, the cylinder houses the pistons. I would try sliding it all the way down, and giving it a good jerk upwards. Repeat as necessary, and it should slide apart. Sounds like your rings at least are shot anyway, so I wouldn't be concerned about further damaging them.
davomoto
64 CB77
63-7 CB77 Cafe'
67 CL77
64 CL72
66 CL77 big bore flat tracker
Many others!

big-b
honda305.com Member
Posts: 179
Joined: Mon Jul 26, 2004 12:45 pm
Location: Ashland, Mass.

Post by big-b » Mon Sep 06, 2010 7:51 pm

Ya i meant the cylinder, the head is already off. I'll give it a good yank tomorrow and see what happens.

Brian

LOUD MOUSE
honda305.com Member
Posts: 7817
Joined: Mon Aug 15, 2005 8:23 am
Location: KERRVILLE, TEXAS

Post by LOUD MOUSE » Mon Sep 06, 2010 8:35 pm

Ya do want to be careful as the pistons exit the sleeves.
If they CANT/don't come streight out ya can/may/will crack the bottom of the sleeve.
If ya have the 180 crank work each piston out at a time. .......lm


big-b wrote:Ya i meant the cylinder, the head is already off. I'll give it a good yank tomorrow and see what happens.

Brian

shooter_bighorn@yahoo.com
honda305.com Member
Posts: 11
Joined: Wed Sep 08, 2010 11:44 am
Location: ny

Post by shooter_bighorn@yahoo.com » Wed Sep 22, 2010 12:28 pm

ive got same problem i can get one piston out of sleeve but other one hangs up dont wanna beat on it but i get full travel up and down with piston in the bore but one side will not come out of the jug can i take the motor and use a block of wood and tap it with a hammer or to risky?????
Attachments
bike 002.jpg
bike 003.jpg
1965 superhawk
1965 superhawk

bikedoctor99
honda305.com Member
Posts: 154
Joined: Sat Aug 14, 2010 7:11 am
Location: North Jersey

stuck piston

Post by bikedoctor99 » Wed Sep 29, 2010 1:29 am

tapping the piston with wood and hammer should be ok. you should rotate the motor so you can spray more kroil between the bottom of the piston and cylinder, also cut or fit a block of wood between the bottom of the cylinder and case to support the cylinder-set the cylinder at a position that will allow the crank to rotate as the piston moves downward. at this time i would let the kroil work over night. reset the motor to upright. when you tap firmly onto the piston, use a soft wood(pine 1 1/2" square will do the trick)you may have to be a bit forceful. good luck!!

Post Reply




 

CB-77 | CYP-77 | Road Test | Riding Log | Literature | Zen | Marketplace | VJ Survey | Links | Home