Cylinder head came off. Here's How. It was a lot of work

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DennisMo

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Success. It took an hour. The problem was that the rear stud on the head (that points down) was frozen to the cylinders.

MANY THANKS TO LUDWIG FOR HIS SUGGESTION AS BELOW

I put a bolt under both of the two front stud nuts that face down. I then loosened the two nuts which pinched the bolts and forced the head up!
But the head clearly was frozen at the back single stud so I hammered front and back of cylinder up from both sides (front and back) with hardwood and a maul.
Many thanks to all who took a look at the problem.
Now I need a helper to get the head and pushrods out.
This is first time taking my 850 head off so I am learning thanks to you all.
Dennis

Cylinder head came off. Here's How. It was a lot of work
 
L.A.B. said:
You shouldn't necessarily need a helper as it's should only be a matter of feeding the pushrods up into the head and then tilting the head back until it can be lifted clear. I've never needed a helper to do this.
Click to expand...
You're absolutely right, but in my case, being old and having only one good arm, it sure is nice to have someone handle the oily pushrods for you! I usually don't have help so I get it done by myself, but any unskilled helper makes it much easier!
 
Had a friend help and it took half an hour to get the pushrods up.
But that is first time. It was hard to figure out where to place them and how to orient the head.
But next time will be easier!
So tomorrow off comes the cylinders.
And pullout the rocker shafts with heat gun applied.
Thanks
Dennis
 
Have heard removing front iso bolt and letting front of engine lower down gives a few precious inches more clearance of head for r&r.
 
DennisMo said:
Success. It took an hour. The problem was that the rear stud on the head (that points down) was frozen to the cylinders.

MANY THANKS TO LUDWIG FOR HIS SUGGESTION AS BELOW

I put a bolt under both of the two front stud nuts that face down. I then loosened the two nuts which pinched the bolts and forced the head up!
But the head clearly was frozen at the back single stud so I hammered front and back of cylinder up from both sides (front and back) with hardwood and a maul.
Many thanks to all who took a look at the problem.
Now I need a helper to get the head and pushrods out.
This is first time taking my 850 head off so I am learning thanks to you all.
Dennis

View attachment 123000
Click to expand...
Well done, but normally only the rear nut is needed.
Loosen it a few threads so that the wrench can engage it from the top down.
With the right wrench, the head will lift off in no time.
Cylinder head came off. Here's How. It was a lot of work

No need for hammers or crow bars..

btw: that nut is 13.25 mm wide ( 1/4 W)
I reduce it to 13 mm for a better choice of wrenches and some extra space.
 
Last edited:
batrider said:
I use rubber bands. Some stuff rags in. Need to hold the head up with a block of wood while you shove them up in there.
Click to expand...
I use rubber bands when putting then head on - makes it easy. Seems difficult to manipulate the head, deal with oily pushrods, and get rubber bands in place to take the head off so I haven't tried it - will next time!
 
DennisMo said:
Had a friend help and it took half an hour to get the pushrods up.
But that is first time. It was hard to figure out where to place them and how to orient the head.
But next time will be easier!
So tomorrow off comes the cylinders.
And pullout the rocker shafts with heat gun applied.
Thanks
Dennis
Click to expand...
Why do you wish to remove the rocker shafts ?
 
Tornado said:
Have heard removing front iso bolt and letting front of engine lower down gives a few precious inches more clearance of head for r&r.
Click to expand...
Sounds good but the engine won't lower much as the frame becomes narrower and closer to the engine.
 
baz said:
Why do you wish to remove the rocker shafts ?
Click to expand...
Review your symptoms, if they are only blue smoke out of the exhausts and water in the oil then rockers shafts are not involved, only touch them if when inspecting the heads the rockers are loose on the shafts. Stick to only what could be causing the symptoms before you end up with a complete rebuild. Now is the time to inspect the head to see where the oil is coming from, is it the inlet guide seals or valve to guide clearances, the oil drain being blocked. Look at the combustion chambers and see how coked up with carbon they are and if one side is different to the other. Turn the engine over and inspect the bores, are they scored. I would take the barrel off as you are in so far but gather all the clues as you disassemble or they will be removed. Post pics as you go.

The objective is to fix the issues at least cost and effort and to only do it once,
 
I just pulled my head for the first time to replace bent pushrods... apparently due to valves not being adjusted properly. Pulled the barrels to inspect lifters as well No obvious issues althought I noticed the my '74 850 MK2 did not have a base gasket. Is that common? I do see them for sale...
 
marshg246 said:
I use rubber bands when putting then head on - makes it easy. Seems difficult to manipulate the head, deal with oily pushrods, and get rubber bands in place to take the head off so I haven't tried it - will next time!
Click to expand...
I have a lovely, bike friendly, wife with small hands.
 

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