replacing head gasket on model b engine

splicr30

splicr30

Junior Member
I have a model b engine and my 30 model a sedan. going to replace a head gasket tomorrow I already have a head off is there anything that I should look out for be careful of any tips. and what about the torque specs?
 
Yes there is. There are 2 steam vent holes near the center (#1) head stud. I have found that the holes in some gaskets for these vent holes do not line up. See picture. I had at least on gasket fail because of this. What I did was to plug up these 2 holes in both the head and block.

Bob
 

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Bob, how could this misalignment cause the gasket to fail as there would be no pressure to speak of there? How did the falure manifest itself? Thanks, I'm just curious.
 
If you look at the attached picture you can see what happened. The arrows point to the problem. Look at the indentations on the gasket. The steam holes were very close to the edge of the gasket. Eventually there was a leak resulting in water in the cylinder. Some gaskets were better than others but they were all too narrow around the steam holes so I plugged the holes so I can use any of the gaskets.

Bob
 

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Vince,

I did not have a Victor 900 Model B gasket or a Best #573 Model B gasket to try. The issue is not just the hole location it is also the width of the gasket around the holes. If the gaskets had more "meat" then the hole position would not be as much a problem. As you can see from my previous pictures the hole in the block is very close to the edge of the gasket. The attached picture shows the failed gasket and a red outline of a used gasket that has enough "meat" on it. The old gasket did not have any markings so I do not know what brand/model it was.

Bob
 

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What was the purpose of the steam holes ? I have a "B" engine and have some black liquid oozing out the side of the head between # 3 & # 4 cylinders . Put in some bars leak hoping this would fix it ,did not fix it . Now I am going to retorque the head bolts which I have been avoiding as I am concerned about stripping the bolts out of the block . If retorquing does not work I will be replacing a head gasket and will face the same problems as you.Not to excited about tapping and threading the block.
 
Those two"steam" holes are not hard to plug.When I installed a 5.9 Brumfield head on a B block,I used a 1/8" pipe tap & tapped the holes just enough so that when the brass plugs were tightened down with an allen wrench,they protruded just a few thou above the deck,then filed them until flush with deck.Then I filled the holes in plugs with JB weld & filed flat.I used the Felpro 7013 gasket.
 
I would also like to know about the steam holes. I'm wondering if this is why I am getting a slight bit of water in #2 and #3 cyl.
TomH
 
I plugged the steam holes because I wanted to be able to use a greater selection of the available gaskets.

The steam holes were added to the Model B engine to relieve any steam that might develop near the #1 stud. The Model A engine did not have these holes.

In my case I figured that the chance of a leaking gasket outweighed the chance of a steam build up causing problems.

Bob
 
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