Topic: Any advice on separating cylinder head from cylinder block?

[JBCB500]

When I disassembled my F2 last night I ended up having to pull the head and the cylinder block off together as I couldn't get them separated.  I have removed all bolts/nuts, including the four underneath the 6 "pucks".  I have protected the head whilst holding the entire thing steady and attempting to drive them apart by hammering a piece of wood up cylinder one or four, yet still nothing.  Is there something I can soak this in or some other tried and tested method?

Thanks

JB

[greenjeans]

There are 2 little slots for a screw driver on either side.  I was hesitant to use them the first time, but after banging, and banging, and banging, and heating, and banging with a mallet & a block of wood, I gave it a shot.  It worked, so I mumbled a few of my best curse words.

[uksparky]

Just had the same problem yesterday, like greenjeans said 2 slots ...i used a wide blade screwdriver and a 10mm wrench against the fins, be gentle it will move

[ekpent]

 I used some stout plastic wedges I had around the shop on a 750 this winter.

[Stev-o]

I just did this too, used a chisel....very carefully.

BTW - I took the head and cylinders off the case together and then separated them.

[754]

If its the motor they mashed the ring under the cylinder, they probably glued the head and cylinder together.
 Maybe if you put it upside down, solvent in the chambers higher than the head gasket, may help break the bond..

[madmtnmotors]

If its the motor they mashed the ring under the cylinder, they probably glued the head and cylinder together.
 Maybe if you put it upside down, solvent in the chambers higher than the head gasket, may help break the bond..

I recently had a head and cylinders that some goob of a PO used some sort of industrial adhesive on both sides of the head gasket. When they finally separated I had delaminated the head gasket, half of which remained firmly attached to the head and the other half firmly attached to the cylinders.

ARRRRGHHH! 

[chewbacca5000]

I would not bother with the days of scraping you are bound to go through to clean those back up.  I would just buy new jugs.  Lot less work.  I hate scraping.

[RAFster122s]

Could even pay a machine shop to separate then but their hourly tends to be higher than your own...a good stiff drink loosens lips often, does not usually work on stuck gaskets.  Might help dull the pain if you slip with the screwdriver or wrench though.

Glad you got them to separate.

[Stev-o]

I would not bother with the days of scraping you are bound to go through to clean those back up.  I would just buy new jugs.  Lot less work.  I hate scraping.

Drop them at a machine shop and have them milled flat. Removes the gasket immediately too 

My machinist offers bead blasting whenever parts are in for boring or a valve job   

[754]

Ummmmmm.. I think they are still stuck together.
If you can try to keep it in centre of gasket, sometimes a knife can be used as a wedge. ..gotta be ground even on each side.. Careful its tricky.

[JBCB500]

Yep, still stuck together.  Although I haven't tried any of these methods yet, but when I get back to it, I will!

Thanks as always for all of the input gents.

[Don R]

 I recently used wedges under the bottom fin of the head, one from the front one from the back so they stay level. Do that on each end, put on some preload and heat it all with a hot air gun. The pry points are at the rear of the head, you can see the bulge in by the cylinder. Pry at the base of the fin, not on the edge. Good luck.

[Duanob]

Could even pay a machine shop to separate then but their hourly tends to be higher than your own...a good stiff drink loosens lips often, does not usually work on stuck gaskets.  Might help dull the pain if you slip with the screwdriver or wrench though.

Glad you got them to separate.

I dunno man, there is something about getting freshly machined and cleaned parts from the shop that's better than christmas morning!

[tlbranth]

I made some wedges from ironwood. But I think plastic tree-falling wedges would work as well.

[drumstyx]

If its the motor they mashed the ring under the cylinder, they probably glued the head and cylinder together.
 Maybe if you put it upside down, solvent in the chambers higher than the head gasket, may help break the bond..

I recently had a head and cylinders that some goob of a PO used some sort of industrial adhesive on both sides of the head gasket. When they finally separated I had delaminated the head gasket, half of which remained firmly attached to the head and the other half firmly attached to the cylinders.

ARRRRGHHH! 

At least those surfaces you can machine -- you'd be kinda screwed (or in for a lot of work) if it were on the base gasket!

[DaveBarbier]

If its the motor they mashed the ring under the cylinder, they probably glued the head and cylinder together.
 Maybe if you put it upside down, solvent in the chambers higher than the head gasket, may help break the bond..

I recently had a head and cylinders that some goob of a PO used some sort of industrial adhesive on both sides of the head gasket. When they finally separated I had delaminated the head gasket, half of which remained firmly attached to the head and the other half firmly attached to the cylinders.

ARRRRGHHH! 

At least those surfaces you can machine -- you'd be kinda screwed (or in for a lot of work) if it were on the base gasket!

I've heard of people putting the jugs in the oven upright standing on the cylinder sleeves. After it heats up the aluminum expands and falls down off the steel sleeves. Then it could be machined.

I've only heard about this