Change of Cylinder head gasket

[roenidoc]

Hello, I need to change my cylinder head gasket because I was losing coolant while driving and had exhaust fumes in the cooling system.
Now the head is off and I noticed that the combustion chambers look different on my head than on a friend of mine. 1.) Are there different types?
2.) There is a big water hole on the opposite side of the distributor shaft passage, which finds no equivalent in the engine block, but is only covered by the cylinder head gasket. I'm very surprised, especially since the cooling might be worse at this point. Does anyone know why this large, useless opening is in the cylinder head? Or does this head not belong to the block?
3) The gasket came off easily, I don't see any bumps. Is it still necessary to have the cylinder head ground flat before reassembly?
4) There are new gaskets made of copper, graphite/steel and modern style composite. Which would you recommend?

[Bruce of MN]

This advice is working for me:

https://www.fordbarn.com/forum/showt...te#post1145107

[Bob Bidonde]

Can't help you without a photo of your cylinder head and block surface.

[Bob C]

If you are asking about this hole it's not in the block.

[alexiskai]

Everyone always asks about that hole (and I include myself five years ago). I should sell a silicone block that does nothing but plug up that hole, make everyone feel better about it.

[Charlie Stephens]

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Originally Posted by roenidoc

Hello, I need to change my cylinder head gasket because I was losing coolant while driving and had exhaust fumes in the cooling system.
Now the head is off and I noticed that the combustion chambers look different on my head than on a friend of mine. 1.) Are there different types?
2.) There is a big water hole on the opposite side of the distributor shaft passage, which finds no equivalent in the engine block, but is only covered by the cylinder head gasket. I'm very surprised, especially since the cooling might be worse at this point. Does anyone know why this large, useless opening is in the cylinder head? Or does this head not belong to the block?
3) The gasket came off easily, I don't see any bumps. Is it still necessary to have the cylinder head ground flat before reassembly?
4) There are new gaskets made of copper, graphite/steel and modern style composite. Which would you recommend?

How about a picture of the combustion chamber? Get one of the top of the head since you are taking pictures. There was a high compression for "Police" use, it can be identified by a block letter "B" on the head.

Charlie Stephens

[JayJay]

Originally Posted by roenidoc

Hello, I need to change my cylinder head gasket because I was losing coolant while driving and had exhaust fumes in the cooling system.
Now the head is off and I noticed that the combustion chambers look different on my head than on a friend of mine. 1.) Are there different types?
Yes, the shape of the combustion chambers is different on heads with different theoretical compression ratios. You can see the difference in this website, or else put a picture of your combustion chamber up here and we'll ID it for you.

2.) There is a big water hole on the opposite side of the distributor shaft passage, which finds no equivalent in the engine block, but is only covered by the cylinder head gasket. I'm very surprised, especially since the cooling might be worse at this point. Does anyone know why this large, useless opening is in the cylinder head? Or does this head not belong to the block?
See the discussion by Bob C elsewhere in this thread. Likely this was put in the head as part of the casting process.

3) The gasket came off easily, I don't see any bumps. Is it still necessary to have the cylinder head ground flat before reassembly?

It's never a bad idea to have a head decked (flattened) if you don't know any history. Rather than to look at the gasket, look around all the water passages and head stud holes to see if there is evidence of water seepage. You already know you have a leak, best to get the head decked to remove one possible cause. Or at least check it with a good precision straightedge and feeler gauges. I like to keep any observed deviation from flat to about 0.002 inch (0.05 mm).

4) There are new gaskets made of copper, graphite/steel and modern style composite. Which would you recommend?
I suspect most of us would recommend the graphite composite type (Best Gaskets #509 is a good one). Coat that gasket with a good copper gasket adhesive such as Permatex 80697 (I'm sure there are equivalent products in Germany). Second would be the "original" full copper type. Experience with the "modern" style has been mixed, I tried one once and was disappointed (it still leaked, even with a freshly decked head).

After you get your new gasket installed and the head torqued, don't forget to retorque the head several times after driving it until it stabilizes. One good schedule is to torque it upon installation, again after a warmup to running temperature and then a cooldown, again after say a 15-25 mile (25-40 km) drive, then again at about 100 mi (150 km). 500 miles (800 km) after that.

Chris, greetings from California.

You've ask some good questions. I've responded above in red.

[JayJay]

Originally Posted by Charlie Stephens

How about a picture of the combustion chamber? Get one of the top of the head since you are taking pictures. There was a high compression for "Police" use, it can be identified by a block letter "B" on the head.

Charlie Stephens

I believe only the Ford heads were marked with the "B" for the 5.2 version. There are lots of aftermarket heads that were also 5.2, I have "Model A" 5.2 head. Vince Falter's discussion is excellent!

[roenidoc]

Yes, this is the hole whose purpose I do not understand.

[alexiskai]

Originally Posted by roenidoc

Yes, this is the hole whose purpose I do not understand.

Its purpose is to facilitate the removal of sand during the casting process. It has no function as part of the engine.

[nkaminar]

You can use some Plastigauge to see if the fit of your head to the block is OK. Put the gauge at different locations and bolt down the head without a gasket. There should be no place with a gap greater than 0.002 inch (0.05 mm). If you have gouges or scrapes in the block or head you can fill them in with JB Weld after cleaning with acetone and them sand them flat with fine sand paper wrapped around a flat file.

[roenidoc]

Sorry for not sending pictures! I didn't know how to manage.
In the meantime, I got along very well and I have been successful.
I thank you all very much for the good advice!
I am very busy at the moment with work and with preparation of a trip (Will fly to Dearborn next week and look at the Ford museums).