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Mini SPI – Why is there a coolant leak through the head gasket?
In this new episode of the restoration of the Mini 1275cc SPI we will answers the (damn) question: Why is there a coolant leak through the head gasket?
In the previous episode we summarized all the steps we did until now in the rebuilt engine from the Mini, and we could see that, even without starting the engine, we had a coolant leak in the head gasket. What a f*cking shit.
But this is not finishing here, this British f*cker will not defeat us. In this new episode we’ll perform thousands of tests until we find the solution!
You have 20 minutes of video ahead, where we will see:
- How to remove the cylinder head, check for possible damage in the gasket, some misaligned hole, defective seals, etc.
- How to check the flatness of the cylinder head. Let’s remember: the cylinder head was worked in an specialized workshop but, would the flatness be enough?
- We will check the flatness of the engine block. It was checked in the workshop and they said it was ready to be assembled but, will it be within tolerances or we will need to disassemble the engine, and work it again?
- We will sand the engine block with a very light sandpaper (grit size 500, 600 and 1000). In diagonal alternative and then with grit size 1000 with diagonal and circular movements. Will it be successful or will we mess things up?
- We will rework the thread in three phases of 3/8 inches. Will these threads be so dirty that make the tightening torque wrong?
- Thread cleaning with gasoline and a sucker to clean all the sh*t. Will it be effective?
- First we will measure the depth of the engine block threads and the studs. Also, we will measure the total length of the studs. Could be the dirt or a possible difference in length the root cause of the coolant leak?
- Cleaning of the engine block, cylinder head and a new gasket. We will use the Payen AF470 or the GEC300?
- New studs, nuts and washers.
- Tightening in 2 steps: 34 and 68 Nm (checked with 3 different torque wrenches).
- Top up of the coolant circuit and… solved? We will see.
Finally, we will show you our conclusion on what has been the root cause of this problem.
We must thank everybody: we received hundreds of comments, messages and whatsapps helping us, with tips and suggestions of checkings to find the cause of this problem. We made all the ones you suggested and they are summarized in this video.
Will they be useful? Will the problem be solved? Wait and see! 😉
Thanks a lot again!