In The Dark At This Point
I looked at some old data from 2018, after the last rebuild, and found an interesting item. The compression check that was done after 6 passes at the track, had #5 cylinder at exactly the same pressure, 210 psi, as the check I did about two weeks ago. The other cylinders were about 15% higher and I thought #5 just had not seated yet. There might, or most likely, had been a problem with #5 way back then. Between August of 2018 and March of 2021, wee have only made about 40-50 passes. The recent compression check, compared to the 2018 compression check, indicates the other three cylinders on the left side have fully seated and their numbers are approximately 30% higher than #5 cylinder. The leak-down check is where the problem shows best. Number 5 cylinder is 32% lower than the others on that side. The left bank, 1-3-7, were about 82% and #5 was 50%.
I called Stef’s Oil Pans about a new oil pump for the new engine and a few questions I had about the Gen IV and Gen V/VI block requirements. I am still not understanding the outside physical difference. Some time, I am as dumb as a brick.