Briggs and Stratton Intek Plus 18.5HP How Flat does the head need to be for copper gasket?
- Thread starter nillvurt
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I'd start with 220, progress to 400 then 800 wet/dry paper. Let the PAPER DO ALL THE WORK. Use a spray bottle with soap and water. Keep rotating the paper as you clean up the area.
This is aluminum, no need for aggressive grits here. Get a small piece of plate glass from a glass shop. They have scrap laying all over their shops.
No wonder you have a leak aggressively using 100 grit LOL. S l o w i t d o w n a little.
sgkent
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rotate the piece and pattern you do. Another option is find a machine shop with a good belt sander that does NOT have a new belt on it cause that is soft aluminum. They can flatten it in seconds. I used to lay small heads, manifolds etc on a belt sander, move them to a couple different positions so it sanded evenly and in a minute I had a level surface. One thing you will run into is that if you keep milling that head you are raising compression which will cause other issues on a worn engine.
You used a copper head gasket. Copper has no give if it is hard. It gets annealed to soften it so it can compress. The Type 4 VW engine I have on a bus uses copper rings on the exhaust to seal it against the head. If they are put on as is the copper is so hard the copper rings will bounce and ring like a small bell if you drop one on concrete. But if they are annealed to cherry in color they get softer so if one drops it then it will go thud and deform. That has to be done on them before using them or they are too hard to deform to seal. I use factory gaskets myself on engines, even when in my racing days and have never had one not seal. I've had blown head gaskets on engines but it always happened over time.
You used a copper head gasket. Copper has no give if it is hard. It gets annealed to soften it so it can compress. The Type 4 VW engine I have on a bus uses copper rings on the exhaust to seal it against the head. If they are put on as is the copper is so hard the copper rings will bounce and ring like a small bell if you drop one on concrete. But if they are annealed to cherry in color they get softer so if one drops it then it will go thud and deform. That has to be done on them before using them or they are too hard to deform to seal. I use factory gaskets myself on engines, even when in my racing days and have never had one not seal. I've had blown head gaskets on engines but it always happened over time.
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yes. Make it flat again.
Have done three head gasket jobs on the KT735 shees what lousy machine work. You can see the bad machining on the heads. When you do head gaskets on an engine that only has one blown do you do them both or just the blown one. I do them both.
sgkent
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don't hold the outside edges when you mill it, and make sure the piece of glass is thick enough to remain flat. I use an old piece of 3/8" glass. Let the sandpaper do the work. Cover the area in a sharpee or prussian blue dye if you have any, so you can see when you are flat.