[DRG-ler]

Eeeiei,... sooo many answers. I try to work through the essentials from the top down.

If it was mine and it ran well and had good compression,I would not disturb it.

I firmly believe in "if it aint broke, don't fix it"

It only needs a new head gasket. Why are you trying to find trouble?

The cylinders look great with the exception of a little bit of corrosion on #2. Cast iron has a unique property in that it takes on a mirror shine after being broken in. The graphite and iron produce the shine. You only need to hone the cylinders if you are going to put new rings in and only because it helps the rings to seat.

It is precisely because of THESE statements that I am asking here. One is too fixated on modern materials. If the cylinder wall on a modern engine looked like this, everyone would say it's gone. The oil film would tear as soon as the engine was started and the pistons would seize up. Anyone who, like me, does not know the properties of the material pairing of iron and graphite will inevitably draw the wrong conclusions. So a big thank you for the explanation. I'm going to leave everything as is and only clean, dry and oil a little when assembling.

There really isn't any corrosion. That should be an optical illusion.

As for the pressure drop test (25%)... I did that a while ago. I used this tester for that. The pointer stopped at 25%, in the clearly green area. This confirms that the piston rings and valves are properly tight. No reason to make any repairs.

The carbon on the pistons is not excessive so I would say your rings and valves are fine.

But that's only been the case for the last 180km. Before everything was clearly black and full of carbon. That's a flaw I'm looking for in my carburetor. I had a replacement carburetor from my uncle for the last 180km, where the engine only uses half the petrol. 9 instead of 18L/100km. With these carburetors, everything has actually burned itself free. I will probably have to overhaul my carburetor.

What I am unclear of is if the head gasket was burned, I would assume you had either a combustion leak -or a water leak? If it was a combustion leak, is that the area I am seeing between #3 and #4 cylinder? If so, why were all the leakage readings the same? Why were the cylinder leakage numbers of the affected cylinders not different??

I also asked myself this question, especially since the pressure loss test was only carried out when the development of the noise indicated a defect! But the answer is quite simple. The pressure loss test is only tested with 2 bar. The head gasket was still sealed at first. The pressures during compression / combustion are many times higher, even with low compression. That's why the error wasn't noticed there. If I had done a compression test, I would have noticed the defective seal sooner. But I didn't have that gauge back then.

Lessons learned.

100% agree



Greetings Andy