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Need Help!: Cylinder Head Stuck to Cylinder!!

Posted: June 10th, 2009, 5:17 pm
by Purplehaze896
Ok, so I've been putting rebuilding my '88 CR500 that I picked up and it's coming along pretty good, but I have been trying to get the damn head apart from the cylinder and it ain't happenin.

It looks like the front few studs have rusted, and I think that is what's holding it. I've tried heating it, soaked it in pb blaster, pb while heated, and have beat it with all sorts of plastic mallets.

The cylinder is in pretty good shape, I can still see some cross hatch. It looks like it has just been sitting for a while.

Does anyone have any suggestions? This is really getting aggravating!!! I just want to ride!!! :evil:

Posted: June 10th, 2009, 6:14 pm
by lewisclan
maybe try filling thhe cyl up with water and put the plug back in and try to kick it over . you will have to have the reed installed also . make sure its on the bottom of the stroke

Posted: June 10th, 2009, 6:30 pm
by Joshwfl
:shock:
I think I'd be too scared of cracking the case at the kicker. I understand the logic, but will the cylinder really hold enough water for that to work? Wouldn't the water run through the exhaust rather than compressing?

Posted: June 10th, 2009, 7:13 pm
by AlisoBob
Drain the coolant, loosen the cylinder head nuts two turns.... start the mutha' up!!!!

Posted: June 10th, 2009, 7:18 pm
by Roostius_Maximus
2 things could have happened

A: the wrong nut was used and the head has mashed into the threads
B: the newer thin style head gasket was used and the head actually fit snug on the stud where it tapers out at the base. I was unaware of this problem until my af build when i used a '00 head on an 87 jug with a thin head gasket. Before the head contacted the gasket it actually sat up on the studs. I taper reamered the holes slightly for clearence, but deffinately an issue using an older jug (85-88 ) without the original thick head gasket.

take the jug off with the head on it, get a log or fencepost in the cylinder and pound it off of there, or sell it to me real cheap :lol:

Posted: June 10th, 2009, 7:37 pm
by AlisoBob
You dont like my way Roosty?????

:twisted:

Posted: June 10th, 2009, 11:43 pm
by Darrell262
I have an idea, but I don't know if it is good for your problem.

When we put clutches on our sleds and we need the motor to stop moving, we shove nylon rope (the yellow soft stuff) down the cylinder and turn the motor until the piston trys to compress the rope and it stops.

Rope is soft so it shouldnt hurt anything. Try that and try to kick it over? I would think to make sure piston is near top so you don't get rope stuck in a port or anything.

Posted: June 11th, 2009, 6:11 am
by Roostius_Maximus
AlisoBob wrote:You dont like my way Roosty?????

:twisted:
hahaha, i didnt even get to read that, from the time my dial-up loaded the page, i watied for it to give me a reply window and posted you snuck that post in there somehow. It'd work, but point your ass away from the bike cuz it'll likely scare the shit outta you, :lol:

Posted: June 11th, 2009, 7:14 am
by AlisoBob
Roostius_Maximus wrote:it'll likely scare the shit outta you, :lol:

Thats the FUN part!

Posted: June 11th, 2009, 2:18 pm
by ISBB
i kinda like the rope idea.. same concept as water but you dont have to worry about damaging anything or getting water where it doesnt belong.

I would also try the pull the jug and hammer it off from the inside out.. Maybe a 2x4 and a nice big mallet?

Posted: June 11th, 2009, 2:43 pm
by AlisoBob
ISBB wrote:Maybe a 2x4 and a nice big mallet?

sissy.........

Posted: June 11th, 2009, 3:20 pm
by Darrell262
Is there even enough room to pull the jug with the head on?

Posted: June 11th, 2009, 3:46 pm
by Roostius_Maximus
in an 88, 91 , and 03 250 there is

Posted: June 11th, 2009, 4:29 pm
by Purplehaze896
Thanks for the advice guys. I'm going to try that wooden fencepost idea or a 2x4 and mallet.

I don't have the bottom end in the frame or I would try some of the other stuff. I almost have the bottom end together so I'm working on the top end now.

I'll let you guys know what happens! Thanks

Posted: June 11th, 2009, 4:42 pm
by racein01
4 sure ripe the whole show off and give her a thump with a bit of timber.

Posted: June 13th, 2009, 4:22 am
by CR500R7
Im with Roostius_Maximus on this one. :wink:

Posted: June 13th, 2009, 1:24 pm
by AlisoBob
CR500R7 wrote:Im with Roostius_Maximus on this one. :wink:

Image

Posted: June 13th, 2009, 3:23 pm
by 100hp honda
this is better than the ending of a good movie. we will be waiting to see how it turned out :lol: :eatdrink:

Posted: June 14th, 2009, 7:13 am
by Purplehaze896
Roostius_Maximus wrote:2 things could have happened

A: the wrong nut was used and the head has mashed into the threads
B: the newer thin style head gasket was used and the head actually fit snug on the stud where it tapers out at the base. I was unaware of this problem until my af build when i used a '00 head on an 87 jug with a thin head gasket. Before the head contacted the gasket it actually sat up on the studs. I taper reamered the holes slightly for clearence, but deffinately an issue using an older jug (85-88 ) without the original thick head gasket.
Roost, I think you hit the nail on the head with that. I have Monday off this week from work so I will have time to beat this damn thing off. I will let you guys know how it turns out and post a picture to see what the deal is.

Posted: June 14th, 2009, 7:56 am
by sabreguy
I like Bob's idea but have a video camera rolling when you fire that biotch up!! :lol: :lol: :lol:

Posted: June 15th, 2009, 3:02 am
by CR500R7
:lol: :lol: :lol:

Posted: June 15th, 2009, 6:58 am
by lewisclan
well how did it go

Finally!

Posted: June 18th, 2009, 5:16 pm
by Purplehaze896
It came off!! Spent about 10 minutes with the "FencePost" method :lol: . Now I can finally start on the top end. Thanks for the help guys!

Here is a picture of the bike. I found out that a member here used to own it and sold it to another member that took it apart to part out but I ended up buying the whole lot. This is what it looked like before disassembly:
Image


I'm planning on doing a AF conversion with the motor when I come across a good deal but I'm just gonna ride the steelie for a while. :D

Posted: June 18th, 2009, 6:08 pm
by Joshwfl
I recognize that garage,,,,,,,,,,,,,,,

I bought that 1st as a parts bike, but it ran sweet, so it went to another member.

That was the leftover plastic from my 86 too.............Man I miss my 86
Image

Posted: June 19th, 2009, 1:39 am
by CR500R7
I knew the fence post would work, did not expect it to take 10 minutes though.
What did the studs look like though, trashed :?:
BTW bike looks nice, should enjoy it.