Leak Down & Compression Test

I finally managed to get the leak down test done today.

As suspected the compression in each of the cylinders is down, especially the number 1 cylinder. The leak down test also revealed just what the engine will achieve with new piston rings fitted.

The results were:
#1: 150psi
#2: 160psi
#3: 170psi
#4: 170psi

Essentially the rings are worn enough for some oil to enter the compression chamber causing the blow by problem that I'm experiencing on off throttle freewheeling and hard acceleration.

By pouring a small amount of oil into the cylinder we then got 180psi across all four cylinders. What that means is the rings are definitely worn, and sorting that would not only cure the blue smoke but also restore the lost power.

Almost a year ago the rolling road test showed 125.6hp at the rear wheels - not bad for just shy of 204, 000 miles and twenty-six years of use. That equates to around 147 flywheel horsepower which is 16hp down on the 163 when new.

Now I know what to do going forward. It's engine rebuild time for certain and I've got a few things on my shopping list.

Comments

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