Removing Lehman Head

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Dave_E

Senior Member
Joined
Sep 2, 2014
Messages
276
Location
USA
Vessel Name
Agnus Dei
Vessel Make
36' Shin Shing
Hi All,

Got the head ready to lift off (way too heavy for one person) and the first thing I notice as I lifted on it... it just slides on the block... no corner bushings. Can they be added? Poor design in my book. I heard they did come that way. ?

Dave
 

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Lots of engines are that way - positioned by the head bolts. You can add positioning pins, but in the wrong place could lead to cracking.
 
You could remove a couple of the head bolts and screw in a stud in their place until the head is installed back on the block, then remove the studs and install the head bolts.
 
Are you sure alignment pins or bushings are not supposed to be there? Been a good while since I did a FL head, but most have some sort of alignment method like a pin or bushing. Some mechanics forget them, not good.
 
A lot of things will have 2 bolt holes slightly different from the rest. If you look closely one will be a tight fit on the bolt, another will be slightly slotted with the slot aligned with the tight fit hole. The rest will be a loose fit on the bolts. It is a good and cost effective what to align parts that are bolted together.

If there is any question of aligning gaskets I cut the heads off some longer bolts, round of the cut ends and cut a slot into that end so I can turn my home made alignment pins out with a screw driver. Then I put my alignment pins into the threaded holes corresponding to the 2 different bolt holes.

I have taken apart a lot of things where the gasket was chewed up because it was not aligned correctly and the person just ran the bolt down until it caught. Not very impressive workmanship IMHO.
 
Looking at my manual it appears there are 2 dowels in the block.
One at 5/16 dia and one at .392 dia.
 
Might I ask what was the reason for the removal, and how did you determine such?

And, more photos, please!

Jason
 
IIRC, mine didn't have long pins to align, so I just used some wooden dowels as suggested by someone.
 
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