Compression Check

[Andre]

Did a compression check on my 14 to obtain some indication as to the condition of the pertinent engine parts and as a baseline for future reference.

Pertinent engine parts are cylinder walls, pistons, piston rings, valve seating, and head gasket.

I have 2 compression tester. On one I had to file down the adapter as it was to big to fit into the channel for the spark plug cap.

Findings:

1. All cylinders had identical compression.
2. There was a large difference between the compression tester.

a) 1050 kPa b) 1247 kPa

The compression specifications are:

Standard - 1 180 kPa
Limit - 880 kPa
Difference - 200 kPa

As per Suzuki, if all readings are below 1 100 kPa, engine should be overhauled (there are also other parameters when the engine should be overhauled). According to reading a), I should overhaul the well working engine. No oil dripping, beautiful spark plug pictures, no oil where it shouldn't be, no smoke from the pots.

According to reading b), I have lots of room to spare before I even reach standard compression.

So what is one to do when doing a compression check. If in doubt do it/get it done with a calibrated compression tester. They are pricey though; a couple 100 € I heard.

For me I have no doubts that my 14's compression is fine. Should compression fall by over 7% of my baseline, I have a compression check done with a professional calibrated tester before I make a decision to overhaul the engine.