|Posted on Thursday, January 08, 2004 - 08:41 pm: ||
I am trying to remove the head from a single cylinder four stroke engine -it's an Australian "Clae Fisherman 6". The head is held on with six studs and I've got the nuts off four, and sheared of the other two flush with the head.
I've tried :-
penetrating oil around the studs,
hitting the side of the head near each stud,
driving a cold chisel under the head,
But she won't budge.
Any good ideas out there?
|Posted on Thursday, January 08, 2004 - 10:23 pm: ||
Can you seal all the passages in the cylinder and head that lead to/from the combustion chamber? Fill the combustion chamber full of oil leave no air space and then take a grease gun and use it to build up hydraulic pressure under the head. This assumes the case that the remaining studs are opposite not adjacent to one another. This should start it to move and once that happens relieve the pressure and take a lead hammer and bang the head down on the cylinder and then repeat the process trying to really loosen up the rust around the studs. If that doesn't work then put it in a milling machine and take a two flute milling cutter and in effect drill out the studs. but leave enough so you can use a pipe wrench to unscrew the remnants of the studs. Dont use a twist drill as they can walk use a two flute milling cutter just under the sise of the bore
for the stud.
|Posted on Sunday, January 11, 2004 - 06:25 am: ||
Len.....I have had this problem and i do sympathise .I took the trouble to make some ''Fox Wedges'' ,ie wedges with only a slight taper ,starting with an almost sharp edge and ending at about 6mm and at least 25mm wide .Make them out of good quality steel and harden them but not too hard . I have eight and i use them only for removing stubborn heads . I find the best hammer to use is a short handled masons Gympie . You will ruin the gasket ,do it gradualy and you will move it
|Posted on Sunday, January 11, 2004 - 04:53 pm: ||
Peters method works real good here in the cold north too. A real heat wave today. Got up to about 15 deg F
|Posted on Sunday, January 11, 2004 - 05:54 pm: ||
I'm a believer in gentle heat. I think the trick here is to remove the studs.
The way in which I have removed recalitrant studs in the past is to take the electric welder and weld some dags or a nut on top on top of each stud.
The heat travelling down should break the bond and the studs can be relatively easily removed.
Once they are removed the CLAE head is flat and a few good hits working from side to side should free it.
One thing to be aware of is that there were several different CLAE heads for this model with only slight differences in the stud placements. It is quite possible to drive a different model head on with the judicous of a hammer. Hence the suggestion to remove the studs.
Just my two bits worth.